source: draft-ietf-httpbis/diffs/draft-ietf-httpbis-p6-cache-09-from-8.diff.html @ 841

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Prepare publication of -09 drafts on March 08

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36<body > 
37  <table border="0" cellpadding="0" cellspacing="0"> 
38  <tr bgcolor="orange"><th></th><th>&nbsp;draft-ietf-httpbis-p6-cache-08.txt&nbsp;</th><th> </th><th>&nbsp;draft-ietf-httpbis-p6-cache-09.txt&nbsp;</th><th></th></tr> 
39      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
40      <tr><td class="lineno" valign="top"></td><td class="left">HTTPbis Working Group                                   R. Fielding, Ed.</td><td> </td><td class="right">HTTPbis Working Group                                   R. Fielding, Ed.</td><td class="lineno" valign="top"></td></tr>
41      <tr><td class="lineno" valign="top"></td><td class="left">Internet-Draft                                              Day Software</td><td> </td><td class="right">Internet-Draft                                              Day Software</td><td class="lineno" valign="top"></td></tr>
42      <tr><td class="lineno" valign="top"></td><td class="left">Obsoletes: 2616 (if approved)                                  J. Gettys</td><td> </td><td class="right">Obsoletes: 2616 (if approved)                                  J. Gettys</td><td class="lineno" valign="top"></td></tr>
43      <tr><td class="lineno" valign="top"></td><td class="left">Intended status: Standards Track                    One Laptop per Child</td><td> </td><td class="right">Intended status: Standards Track                    One Laptop per Child</td><td class="lineno" valign="top"></td></tr>
44      <tr><td><a name="diff0001" /></td></tr>
45      <tr><td class="lineno" valign="top"></td><td class="lblock">Expires: <span class="delete">April 29, 2010   </span>                                      J. Mogul</td><td> </td><td class="rblock">Expires: <span class="insert">September 9, 2010</span>                                      J. Mogul</td><td class="lineno" valign="top"></td></tr>
46      <tr><td class="lineno" valign="top"></td><td class="left">                                                                      HP</td><td> </td><td class="right">                                                                      HP</td><td class="lineno" valign="top"></td></tr>
47      <tr><td class="lineno" valign="top"></td><td class="left">                                                              H. Frystyk</td><td> </td><td class="right">                                                              H. Frystyk</td><td class="lineno" valign="top"></td></tr>
48      <tr><td class="lineno" valign="top"></td><td class="left">                                                               Microsoft</td><td> </td><td class="right">                                                               Microsoft</td><td class="lineno" valign="top"></td></tr>
49      <tr><td class="lineno" valign="top"></td><td class="left">                                                             L. Masinter</td><td> </td><td class="right">                                                             L. Masinter</td><td class="lineno" valign="top"></td></tr>
50      <tr><td class="lineno" valign="top"></td><td class="left">                                                           Adobe Systems</td><td> </td><td class="right">                                                           Adobe Systems</td><td class="lineno" valign="top"></td></tr>
51      <tr><td class="lineno" valign="top"></td><td class="left">                                                                P. Leach</td><td> </td><td class="right">                                                                P. Leach</td><td class="lineno" valign="top"></td></tr>
52      <tr><td class="lineno" valign="top"></td><td class="left">                                                               Microsoft</td><td> </td><td class="right">                                                               Microsoft</td><td class="lineno" valign="top"></td></tr>
53      <tr><td class="lineno" valign="top"></td><td class="left">                                                          T. Berners-Lee</td><td> </td><td class="right">                                                          T. Berners-Lee</td><td class="lineno" valign="top"></td></tr>
54      <tr><td class="lineno" valign="top"></td><td class="left">                                                                 W3C/MIT</td><td> </td><td class="right">                                                                 W3C/MIT</td><td class="lineno" valign="top"></td></tr>
55      <tr><td class="lineno" valign="top"></td><td class="left">                                                           Y. Lafon, Ed.</td><td> </td><td class="right">                                                           Y. Lafon, Ed.</td><td class="lineno" valign="top"></td></tr>
56      <tr><td class="lineno" valign="top"></td><td class="left">                                                                     W3C</td><td> </td><td class="right">                                                                     W3C</td><td class="lineno" valign="top"></td></tr>
57      <tr><td class="lineno" valign="top"></td><td class="left">                                                      M. Nottingham, Ed.</td><td> </td><td class="right">                                                      M. Nottingham, Ed.</td><td class="lineno" valign="top"></td></tr>
58      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
59      <tr><td class="lineno" valign="top"></td><td class="left">                                                         J. Reschke, Ed.</td><td> </td><td class="right">                                                         J. Reschke, Ed.</td><td class="lineno" valign="top"></td></tr>
60      <tr><td class="lineno" valign="top"></td><td class="left">                                                              greenbytes</td><td> </td><td class="right">                                                              greenbytes</td><td class="lineno" valign="top"></td></tr>
61      <tr><td><a name="diff0002" /></td></tr>
62      <tr><td class="lineno" valign="top"></td><td class="lblock">                                                        <span class="delete">October 26, 2009</span></td><td> </td><td class="rblock">                                                        <span class="insert">   March 8, 2010</span></td><td class="lineno" valign="top"></td></tr>
63      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
64      <tr><td class="lineno" valign="top"></td><td class="left">                       HTTP/1.1, part 6: Caching</td><td> </td><td class="right">                       HTTP/1.1, part 6: Caching</td><td class="lineno" valign="top"></td></tr>
65      <tr><td><a name="diff0003" /></td></tr>
66      <tr><td class="lineno" valign="top"></td><td class="lblock">                     draft-ietf-httpbis-p6-cache-0<span class="delete">8</span></td><td> </td><td class="rblock">                     draft-ietf-httpbis-p6-cache-0<span class="insert">9</span></td><td class="lineno" valign="top"></td></tr>
67      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
68      <tr><td><a name="diff0004" /></td></tr>
69      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">Status</span> of this <span class="delete">Memo</span></td><td> </td><td class="rblock"><span class="insert">Abstract</span></td><td class="lineno" valign="top"></td></tr>
70      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
71      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   The Hypertext Transfer Protocol (HTTP) is an application-level</span></td><td class="lineno" valign="top"></td></tr>
72      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   protocol for distributed, collaborative, hypermedia information</span></td><td class="lineno" valign="top"></td></tr>
73      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   systems.  This document is Part 6</span> of <span class="insert">the seven-part specification</span></td><td class="lineno" valign="top"></td></tr>
74      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   that defines the protocol referred to as "HTTP/1.1" and, taken</span></td><td class="lineno" valign="top"></td></tr>
75      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   together, obsoletes RFC 2616.  Part 6 defines requirements on HTTP</span></td><td class="lineno" valign="top"></td></tr>
76      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   caches and the associated header fields that control cache behavior</span></td><td class="lineno" valign="top"></td></tr>
77      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   or indicate cacheable response messages.</span></td><td class="lineno" valign="top"></td></tr>
78      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
79      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">Editorial Note (To be removed by RFC Editor)</span></td><td class="lineno" valign="top"></td></tr>
80      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
81      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   Discussion of this draft should take place on the HTTPBIS working</span></td><td class="lineno" valign="top"></td></tr>
82      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   group mailing list (ietf-http-wg@w3.org).  The current issues list is</span></td><td class="lineno" valign="top"></td></tr>
83      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   at &lt;http://tools.ietf.org/wg/httpbis/trac/report/11&gt; and related</span></td><td class="lineno" valign="top"></td></tr>
84      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   documents (including fancy diffs) can be found at</span></td><td class="lineno" valign="top"></td></tr>
85      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   &lt;http://tools.ietf.org/wg/httpbis/&gt;.</span></td><td class="lineno" valign="top"></td></tr>
86      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
87      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   The changes in</span> this <span class="insert">draft are summarized in Appendix C.10.</span></td><td class="lineno" valign="top"></td></tr>
88      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
89      <tr><td><a name="diff0005" /></td></tr>
90      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">Status of this Memo</span></td><td class="lineno" valign="top"></td></tr>
91      <tr><td class="lineno" valign="top"></td><td class="left">   This Internet-Draft is submitted to IETF in full conformance with the</td><td> </td><td class="right">   This Internet-Draft is submitted to IETF in full conformance with the</td><td class="lineno" valign="top"></td></tr>
92      <tr><td><a name="diff0006" /></td></tr>
93      <tr><td class="lineno" valign="top"></td><td class="lblock">   provisions of BCP 78 and BCP 79.  <span class="delete">This document may contain material</span></td><td> </td><td class="rblock">   provisions of BCP 78 and BCP 79.</td><td class="lineno" valign="top"></td></tr>
94      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   from IETF Documents or IETF Contributions published or made publicly</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
95      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   available before November 10, 2008.  The person(s) controlling the</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
96      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   copyright in some of this material may not have granted the IETF</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
97      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   Trust the right to allow modifications of such material outside the</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
98      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   IETF Standards Process.  Without obtaining an adequate license from</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
99      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   the person(s) controlling the copyright in such materials, this</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
100      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   document may not be modified outside the IETF Standards Process, and</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
101      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   derivative works of it may not be created outside the IETF Standards</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
102      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   Process, except to format it for publication as an RFC or to</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
103      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   translate it into languages other than English.</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
104      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
105      <tr><td class="lineno" valign="top"></td><td class="left">   Internet-Drafts are working documents of the Internet Engineering</td><td> </td><td class="right">   Internet-Drafts are working documents of the Internet Engineering</td><td class="lineno" valign="top"></td></tr>
106      <tr><td class="lineno" valign="top"></td><td class="left">   Task Force (IETF), its areas, and its working groups.  Note that</td><td> </td><td class="right">   Task Force (IETF), its areas, and its working groups.  Note that</td><td class="lineno" valign="top"></td></tr>
107      <tr><td class="lineno" valign="top"></td><td class="left">   other groups may also distribute working documents as Internet-</td><td> </td><td class="right">   other groups may also distribute working documents as Internet-</td><td class="lineno" valign="top"></td></tr>
108      <tr><td class="lineno" valign="top"></td><td class="left">   Drafts.</td><td> </td><td class="right">   Drafts.</td><td class="lineno" valign="top"></td></tr>
109      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
110      <tr><td class="lineno" valign="top"></td><td class="left">   Internet-Drafts are draft documents valid for a maximum of six months</td><td> </td><td class="right">   Internet-Drafts are draft documents valid for a maximum of six months</td><td class="lineno" valign="top"></td></tr>
111      <tr><td class="lineno" valign="top"></td><td class="left">   and may be updated, replaced, or obsoleted by other documents at any</td><td> </td><td class="right">   and may be updated, replaced, or obsoleted by other documents at any</td><td class="lineno" valign="top"></td></tr>
112      <tr><td class="lineno" valign="top"></td><td class="left">   time.  It is inappropriate to use Internet-Drafts as reference</td><td> </td><td class="right">   time.  It is inappropriate to use Internet-Drafts as reference</td><td class="lineno" valign="top"></td></tr>
113      <tr><td class="lineno" valign="top"></td><td class="left">   material or to cite them other than as "work in progress."</td><td> </td><td class="right">   material or to cite them other than as "work in progress."</td><td class="lineno" valign="top"></td></tr>
114      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
115      <tr><td class="lineno" valign="top"></td><td class="left">   The list of current Internet-Drafts can be accessed at</td><td> </td><td class="right">   The list of current Internet-Drafts can be accessed at</td><td class="lineno" valign="top"></td></tr>
116      <tr><td class="lineno" valign="top"></td><td class="left">   http://www.ietf.org/ietf/1id-abstracts.txt.</td><td> </td><td class="right">   http://www.ietf.org/ietf/1id-abstracts.txt.</td><td class="lineno" valign="top"></td></tr>
117      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
118      <tr><td class="lineno" valign="top"></td><td class="left">   The list of Internet-Draft Shadow Directories can be accessed at</td><td> </td><td class="right">   The list of Internet-Draft Shadow Directories can be accessed at</td><td class="lineno" valign="top"></td></tr>
119      <tr><td class="lineno" valign="top"></td><td class="left">   http://www.ietf.org/shadow.html.</td><td> </td><td class="right">   http://www.ietf.org/shadow.html.</td><td class="lineno" valign="top"></td></tr>
120      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
121      <tr><td><a name="diff0007" /></td></tr>
122      <tr><td class="lineno" valign="top"></td><td class="lblock">   This Internet-Draft will expire on <span class="delete">April 2</span>9, 2010.</td><td> </td><td class="rblock">   This Internet-Draft will expire on <span class="insert">September </span>9, 2010.</td><td class="lineno" valign="top"></td></tr>
123      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
124      <tr><td class="lineno" valign="top"></td><td class="left">Copyright Notice</td><td> </td><td class="right">Copyright Notice</td><td class="lineno" valign="top"></td></tr>
125      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
126      <tr><td><a name="diff0008" /></td></tr>
127      <tr><td class="lineno" valign="top"></td><td class="lblock">   Copyright (c) 20<span class="delete">09</span> IETF Trust and the persons identified as the</td><td> </td><td class="rblock">   Copyright (c) 20<span class="insert">10</span> IETF Trust and the persons identified as the</td><td class="lineno" valign="top"></td></tr>
128      <tr><td class="lineno" valign="top"></td><td class="left">   document authors.  All rights reserved.</td><td> </td><td class="right">   document authors.  All rights reserved.</td><td class="lineno" valign="top"></td></tr>
129      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
130      <tr><td class="lineno" valign="top"></td><td class="left">   This document is subject to BCP 78 and the IETF Trust's Legal</td><td> </td><td class="right">   This document is subject to BCP 78 and the IETF Trust's Legal</td><td class="lineno" valign="top"></td></tr>
131      <tr><td><a name="diff0009" /></td></tr>
132      <tr><td class="lineno" valign="top"></td><td class="lblock">   Provisions Relating to IETF Documents in effect on the date of</td><td> </td><td class="rblock">   Provisions Relating to IETF Documents</td><td class="lineno" valign="top"></td></tr>
133      <tr><td class="lineno" valign="top"></td><td class="lblock">   publication of this <span class="delete">document (http://trustee.ietf.org/license-info).</span></td><td> </td><td class="rblock">   <span class="insert">(http://trustee.ietf.org/license-info)</span> in effect on the date of</td><td class="lineno" valign="top"></td></tr>
134      <tr><td class="lineno" valign="top"></td><td class="lblock">   Please review these documents carefully, as they describe your rights</td><td> </td><td class="rblock">   publication of this <span class="insert">document.</span>  Please review these documents</td><td class="lineno" valign="top"></td></tr>
135      <tr><td class="lineno" valign="top"></td><td class="lblock">   and restrictions with respect to this document.</td><td> </td><td class="rblock">   carefully, as they describe your rights and restrictions with respect</td><td class="lineno" valign="top"></td></tr>
136      <tr><td class="lineno" valign="top"></td><td class="lblock">                                                                         </td><td> </td><td class="rblock">   to this document.  <span class="insert">Code Components extracted from this</span> document <span class="insert">must</span></td><td class="lineno" valign="top"></td></tr>
137      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">Abstract</span></td><td> </td><td class="rblock"><span class="insert">   include Simplified BSD License text</span> as <span class="insert">described in Section 4.e</span> of</td><td class="lineno" valign="top"></td></tr>
138      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete"></span></td><td> </td><td class="rblock">   the <span class="insert">Trust Legal Provisions</span> and <span class="insert">are provided without warranty as</span></td><td class="lineno" valign="top"></td></tr>
139      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   The Hypertext Transfer Protocol (HTTP) is an application-level</span></td><td> </td><td class="rblock"><span class="insert">   described in the BSD License.</span></td><td class="lineno" valign="top"></td></tr>
140      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   protocol for distributed, collaborative, hypermedia information</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
141      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   systems.  This</span> document <span class="delete">is Part 6 of the seven-part specification</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
142      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   that defines the protocol referred to</span> as <span class="delete">"HTTP/1.1" and, taken</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
143      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   together, obsoletes RFC 2616.  Part 6 defines requirements on HTTP</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
144      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   caches and the associated header fields that control cache behavior</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
145      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   or indicate cacheable response messages.</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
146      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete"></span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
147      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">Editorial Note (To be removed by RFC Editor)</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
148      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete"></span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
149      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   Discussion</span> of <span class="delete">this draft should take place on</span> the <span class="delete">HTTPBIS working</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
150      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   group mailing list (ietf-http-wg@w3.org).  The current issues list is</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
151      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   at &lt;http://tools.ietf.org/wg/httpbis/trac/report/11&gt;</span> and <span class="delete">related</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
152      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   documents (including fancy diffs) can be found at</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
153      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   &lt;http://tools.ietf.org/wg/httpbis/&gt;.</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
154      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
155      <tr><td><a name="diff0010" /></td></tr>
156      <tr><td class="lineno" valign="top"></td><td class="lblock">   The <span class="delete">changes</span> in this <span class="delete">draft are summarized</span> in <span class="delete">Appendix C.9.</span></td><td> </td><td class="rblock">   <span class="insert">This document may contain material from IETF Documents or IETF</span></td><td class="lineno" valign="top"></td></tr>
157      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   Contributions published or made publicly available before November</span></td><td class="lineno" valign="top"></td></tr>
158      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   10, 2008.</span>  The <span class="insert">person(s) controlling the copyright</span> in <span class="insert">some of</span> this</td><td class="lineno" valign="top"></td></tr>
159      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   <span class="insert">material may not have granted the IETF Trust the right to allow</span></td><td class="lineno" valign="top"></td></tr>
160      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   modifications of such material outside the IETF Standards Process.</span></td><td class="lineno" valign="top"></td></tr>
161      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   Without obtaining an adequate license from the person(s) controlling</span></td><td class="lineno" valign="top"></td></tr>
162      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   the copyright</span> in <span class="insert">such materials, this document may not be modified</span></td><td class="lineno" valign="top"></td></tr>
163      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   outside the IETF Standards Process, and derivative works of it may</span></td><td class="lineno" valign="top"></td></tr>
164      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   not be created outside the IETF Standards Process, except to format</span></td><td class="lineno" valign="top"></td></tr>
165      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   it for publication as an RFC or to translate it into languages other</span></td><td class="lineno" valign="top"></td></tr>
166      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   than English.</span></td><td class="lineno" valign="top"></td></tr>
167      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
168      <tr><td class="lineno" valign="top"></td><td class="left">Table of Contents</td><td> </td><td class="right">Table of Contents</td><td class="lineno" valign="top"></td></tr>
169      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
170      <tr><td class="lineno" valign="top"></td><td class="left">   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5</td><td> </td><td class="right">   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5</td><td class="lineno" valign="top"></td></tr>
171      <tr><td class="lineno" valign="top"></td><td class="left">     1.1.  Purpose  . . . . . . . . . . . . . . . . . . . . . . . . .  5</td><td> </td><td class="right">     1.1.  Purpose  . . . . . . . . . . . . . . . . . . . . . . . . .  5</td><td class="lineno" valign="top"></td></tr>
172      <tr><td class="lineno" valign="top"></td><td class="left">     1.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  5</td><td> </td><td class="right">     1.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  5</td><td class="lineno" valign="top"></td></tr>
173      <tr><td class="lineno" valign="top"></td><td class="left">     1.3.  Requirements . . . . . . . . . . . . . . . . . . . . . . .  6</td><td> </td><td class="right">     1.3.  Requirements . . . . . . . . . . . . . . . . . . . . . . .  6</td><td class="lineno" valign="top"></td></tr>
174      <tr><td class="lineno" valign="top"></td><td class="left">     1.4.  Syntax Notation  . . . . . . . . . . . . . . . . . . . . .  7</td><td> </td><td class="right">     1.4.  Syntax Notation  . . . . . . . . . . . . . . . . . . . . .  7</td><td class="lineno" valign="top"></td></tr>
175      <tr><td class="lineno" valign="top"></td><td class="left">       1.4.1.  Core Rules . . . . . . . . . . . . . . . . . . . . . .  7</td><td> </td><td class="right">       1.4.1.  Core Rules . . . . . . . . . . . . . . . . . . . . . .  7</td><td class="lineno" valign="top"></td></tr>
176      <tr><td class="lineno" valign="top"></td><td class="left">       1.4.2.  ABNF Rules defined in other Parts of the</td><td> </td><td class="right">       1.4.2.  ABNF Rules defined in other Parts of the</td><td class="lineno" valign="top"></td></tr>
177      <tr><td class="lineno" valign="top"></td><td class="left">               Specification  . . . . . . . . . . . . . . . . . . . .  7</td><td> </td><td class="right">               Specification  . . . . . . . . . . . . . . . . . . . .  7</td><td class="lineno" valign="top"></td></tr>
178      <tr><td class="lineno" valign="top"></td><td class="left">   2.  Cache Operation  . . . . . . . . . . . . . . . . . . . . . . .  7</td><td> </td><td class="right">   2.  Cache Operation  . . . . . . . . . . . . . . . . . . . . . . .  7</td><td class="lineno" valign="top"></td></tr>
179      <tr><td class="lineno" valign="top"></td><td class="left">     2.1.  Response Cacheability  . . . . . . . . . . . . . . . . . .  7</td><td> </td><td class="right">     2.1.  Response Cacheability  . . . . . . . . . . . . . . . . . .  7</td><td class="lineno" valign="top"></td></tr>
180      <tr><td class="lineno" valign="top"></td><td class="left">       2.1.1.  Storing Partial and Incomplete Responses . . . . . . .  8</td><td> </td><td class="right">       2.1.1.  Storing Partial and Incomplete Responses . . . . . . .  8</td><td class="lineno" valign="top"></td></tr>
181      <tr><td><a name="diff0011" /></td></tr>
182      <tr><td class="lineno" valign="top"></td><td class="lblock">     2.2.  Constructing Responses from Caches . . . . . . . . . . . .  <span class="delete">8</span></td><td> </td><td class="rblock">     2.2.  Constructing Responses from Caches . . . . . . . . . . . .  <span class="insert">9</span></td><td class="lineno" valign="top"></td></tr>
183      <tr><td class="lineno" valign="top"></td><td class="lblock">     2.3.  Freshness Model  . . . . . . . . . . . . . . . . . . . . .  <span class="delete">9</span></td><td> </td><td class="rblock">     2.3.  Freshness Model  . . . . . . . . . . . . . . . . . . . . . <span class="insert">10</span></td><td class="lineno" valign="top"></td></tr>
184      <tr><td class="lineno" valign="top"></td><td class="lblock">       2.3.1.  Calculating Freshness Lifetime . . . . . . . . . . . . <span class="delete">10</span></td><td> </td><td class="rblock">       2.3.1.  Calculating Freshness Lifetime . . . . . . . . . . . . <span class="insert">11</span></td><td class="lineno" valign="top"></td></tr>
185      <tr><td class="lineno" valign="top"></td><td class="lblock">       2.3.2.  Calculating Age  . . . . . . . . . . . . . . . . . . . <span class="delete">11</span></td><td> </td><td class="rblock">       2.3.2.  Calculating Age  . . . . . . . . . . . . . . . . . . . <span class="insert">12</span></td><td class="lineno" valign="top"></td></tr>
186      <tr><td class="lineno" valign="top"></td><td class="left">       2.3.3.  Serving Stale Responses  . . . . . . . . . . . . . . . 13</td><td> </td><td class="right">       2.3.3.  Serving Stale Responses  . . . . . . . . . . . . . . . 13</td><td class="lineno" valign="top"></td></tr>
187      <tr><td><a name="diff0012" /></td></tr>
188      <tr><td class="lineno" valign="top"></td><td class="lblock">     2.4.  Validation Model . . . . . . . . . . . . . . . . . . . . . 1<span class="delete">3</span></td><td> </td><td class="rblock">     2.4.  Validation Model . . . . . . . . . . . . . . . . . . . . . 1<span class="insert">4</span></td><td class="lineno" valign="top"></td></tr>
189      <tr><td class="lineno" valign="top"></td><td class="left">     2.5.  Request Methods that Invalidate  . . . . . . . . . . . . . 14</td><td> </td><td class="right">     2.5.  Request Methods that Invalidate  . . . . . . . . . . . . . 14</td><td class="lineno" valign="top"></td></tr>
190      <tr><td class="lineno" valign="top"></td><td class="left">     2.6.  Caching Negotiated Responses . . . . . . . . . . . . . . . 15</td><td> </td><td class="right">     2.6.  Caching Negotiated Responses . . . . . . . . . . . . . . . 15</td><td class="lineno" valign="top"></td></tr>
191      <tr><td class="lineno" valign="top"></td><td class="left">     2.7.  Combining Responses  . . . . . . . . . . . . . . . . . . . 16</td><td> </td><td class="right">     2.7.  Combining Responses  . . . . . . . . . . . . . . . . . . . 16</td><td class="lineno" valign="top"></td></tr>
192      <tr><td><a name="diff0013" /></td></tr>
193      <tr><td class="lineno" valign="top"></td><td class="lblock">   3.  Header Field Definitions . . . . . . . . . . . . . . . . . . . 1<span class="delete">6</span></td><td> </td><td class="rblock">   3.  Header Field Definitions . . . . . . . . . . . . . . . . . . . 1<span class="insert">7</span></td><td class="lineno" valign="top"></td></tr>
194      <tr><td class="lineno" valign="top"></td><td class="left">     3.1.  Age  . . . . . . . . . . . . . . . . . . . . . . . . . . . 17</td><td> </td><td class="right">     3.1.  Age  . . . . . . . . . . . . . . . . . . . . . . . . . . . 17</td><td class="lineno" valign="top"></td></tr>
195      <tr><td><a name="diff0014" /></td></tr>
196      <tr><td class="lineno" valign="top"></td><td class="lblock">     3.2.  Cache-Control  . . . . . . . . . . . . . . . . . . . . . . 1<span class="delete">7</span></td><td> </td><td class="rblock">     3.2.  Cache-Control  . . . . . . . . . . . . . . . . . . . . . . 1<span class="insert">8</span></td><td class="lineno" valign="top"></td></tr>
197      <tr><td class="lineno" valign="top"></td><td class="left">       3.2.1.  Request Cache-Control Directives . . . . . . . . . . . 18</td><td> </td><td class="right">       3.2.1.  Request Cache-Control Directives . . . . . . . . . . . 18</td><td class="lineno" valign="top"></td></tr>
198      <tr><td class="lineno" valign="top"></td><td class="left">       3.2.2.  Response Cache-Control Directives  . . . . . . . . . . 20</td><td> </td><td class="right">       3.2.2.  Response Cache-Control Directives  . . . . . . . . . . 20</td><td class="lineno" valign="top"></td></tr>
199      <tr><td class="lineno" valign="top"></td><td class="left">       3.2.3.  Cache Control Extensions . . . . . . . . . . . . . . . 22</td><td> </td><td class="right">       3.2.3.  Cache Control Extensions . . . . . . . . . . . . . . . 22</td><td class="lineno" valign="top"></td></tr>
200      <tr><td class="lineno" valign="top"></td><td class="left">     3.3.  Expires  . . . . . . . . . . . . . . . . . . . . . . . . . 23</td><td> </td><td class="right">     3.3.  Expires  . . . . . . . . . . . . . . . . . . . . . . . . . 23</td><td class="lineno" valign="top"></td></tr>
201      <tr><td class="lineno" valign="top"></td><td class="left">     3.4.  Pragma . . . . . . . . . . . . . . . . . . . . . . . . . . 24</td><td> </td><td class="right">     3.4.  Pragma . . . . . . . . . . . . . . . . . . . . . . . . . . 24</td><td class="lineno" valign="top"></td></tr>
202      <tr><td class="lineno" valign="top"></td><td class="left">     3.5.  Vary . . . . . . . . . . . . . . . . . . . . . . . . . . . 24</td><td> </td><td class="right">     3.5.  Vary . . . . . . . . . . . . . . . . . . . . . . . . . . . 24</td><td class="lineno" valign="top"></td></tr>
203      <tr><td class="lineno" valign="top"></td><td class="left">     3.6.  Warning  . . . . . . . . . . . . . . . . . . . . . . . . . 25</td><td> </td><td class="right">     3.6.  Warning  . . . . . . . . . . . . . . . . . . . . . . . . . 25</td><td class="lineno" valign="top"></td></tr>
204      <tr><td class="lineno" valign="top"></td><td class="left">   4.  History Lists  . . . . . . . . . . . . . . . . . . . . . . . . 28</td><td> </td><td class="right">   4.  History Lists  . . . . . . . . . . . . . . . . . . . . . . . . 28</td><td class="lineno" valign="top"></td></tr>
205      <tr><td class="lineno" valign="top"></td><td class="left">   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 28</td><td> </td><td class="right">   5.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 28</td><td class="lineno" valign="top"></td></tr>
206      <tr><td class="lineno" valign="top"></td><td class="left">     5.1.  Message Header Registration  . . . . . . . . . . . . . . . 28</td><td> </td><td class="right">     5.1.  Message Header Registration  . . . . . . . . . . . . . . . 28</td><td class="lineno" valign="top"></td></tr>
207      <tr><td><a name="diff0015" /></td></tr>
208      <tr><td class="lineno" valign="top"></td><td class="lblock">   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 2<span class="delete">9</span></td><td> </td><td class="rblock">   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 2<span class="insert">8</span></td><td class="lineno" valign="top"></td></tr>
209      <tr><td class="lineno" valign="top"></td><td class="left">   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 29</td><td> </td><td class="right">   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . . 29</td><td class="lineno" valign="top"></td></tr>
210      <tr><td class="lineno" valign="top"></td><td class="left">   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 29</td><td> </td><td class="right">   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 29</td><td class="lineno" valign="top"></td></tr>
211      <tr><td class="lineno" valign="top"></td><td class="left">     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 29</td><td> </td><td class="right">     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 29</td><td class="lineno" valign="top"></td></tr>
212      <tr><td class="lineno" valign="top"></td><td class="left">     8.2.  Informative References . . . . . . . . . . . . . . . . . . 30</td><td> </td><td class="right">     8.2.  Informative References . . . . . . . . . . . . . . . . . . 30</td><td class="lineno" valign="top"></td></tr>
213      <tr><td class="lineno" valign="top"></td><td class="left">   Appendix A.  Compatibility with Previous Versions  . . . . . . . . 30</td><td> </td><td class="right">   Appendix A.  Compatibility with Previous Versions  . . . . . . . . 30</td><td class="lineno" valign="top"></td></tr>
214      <tr><td><a name="diff0016" /></td></tr>
215      <tr><td class="lineno" valign="top"></td><td class="lblock">     A.1.  Changes from RFC 2068  . . . . . . . . . . . . . . . . . . <span class="delete">31</span></td><td> </td><td class="rblock">     A.1.  Changes from RFC 2068  . . . . . . . . . . . . . . . . . . <span class="insert">30</span></td><td class="lineno" valign="top"></td></tr>
216      <tr><td class="lineno" valign="top"></td><td class="lblock">     A.2.  Changes from RFC 2616  . . . . . . . . . . . . . . . . . . <span class="delete">31</span></td><td> </td><td class="rblock">     A.2.  Changes from RFC 2616  . . . . . . . . . . . . . . . . . . <span class="insert">30</span></td><td class="lineno" valign="top"></td></tr>
217      <tr><td class="lineno" valign="top"></td><td class="left">   Appendix B.  Collected ABNF  . . . . . . . . . . . . . . . . . . . 31</td><td> </td><td class="right">   Appendix B.  Collected ABNF  . . . . . . . . . . . . . . . . . . . 31</td><td class="lineno" valign="top"></td></tr>
218      <tr><td class="lineno" valign="top"></td><td class="left">   Appendix C.  Change Log (to be removed by RFC Editor before</td><td> </td><td class="right">   Appendix C.  Change Log (to be removed by RFC Editor before</td><td class="lineno" valign="top"></td></tr>
219      <tr><td><a name="diff0017" /></td></tr>
220      <tr><td class="lineno" valign="top"></td><td class="lblock">                publication)  . . . . . . . . . . . . . . . . . . . . <span class="delete">33</span></td><td> </td><td class="rblock">                publication)  . . . . . . . . . . . . . . . . . . . . <span class="insert">32</span></td><td class="lineno" valign="top"></td></tr>
221      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.1.  Since RFC2616  . . . . . . . . . . . . . . . . . . . . . . <span class="delete">33</span></td><td> </td><td class="rblock">     C.1.  Since RFC2616  . . . . . . . . . . . . . . . . . . . . . . <span class="insert">32</span></td><td class="lineno" valign="top"></td></tr>
222      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.2.  Since draft-ietf-httpbis-p6-cache-00 . . . . . . . . . . . <span class="delete">33</span></td><td> </td><td class="rblock">     C.2.  Since draft-ietf-httpbis-p6-cache-00 . . . . . . . . . . . <span class="insert">32</span></td><td class="lineno" valign="top"></td></tr>
223      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.3.  Since draft-ietf-httpbis-p6-cache-01 . . . . . . . . . . . <span class="delete">34</span></td><td> </td><td class="rblock">     C.3.  Since draft-ietf-httpbis-p6-cache-01 . . . . . . . . . . . <span class="insert">33</span></td><td class="lineno" valign="top"></td></tr>
224      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.4.  Since draft-ietf-httpbis-p6-cache-02 . . . . . . . . . . . <span class="delete">34</span></td><td> </td><td class="rblock">     C.4.  Since draft-ietf-httpbis-p6-cache-02 . . . . . . . . . . . <span class="insert">33</span></td><td class="lineno" valign="top"></td></tr>
225      <tr><td class="lineno" valign="top"></td><td class="left">     C.5.  Since draft-ietf-httpbis-p6-cache-03 . . . . . . . . . . . 34</td><td> </td><td class="right">     C.5.  Since draft-ietf-httpbis-p6-cache-03 . . . . . . . . . . . 34</td><td class="lineno" valign="top"></td></tr>
226      <tr><td><a name="diff0018" /></td></tr>
227      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.6.  Since draft-ietf-httpbis-p6-cache-04 . . . . . . . . . . . <span class="delete">35</span></td><td> </td><td class="rblock">     C.6.  Since draft-ietf-httpbis-p6-cache-04 . . . . . . . . . . . <span class="insert">34</span></td><td class="lineno" valign="top"></td></tr>
228      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.7.  Since draft-ietf-httpbis-p6-cache-05 . . . . . . . . . . . <span class="delete">35</span></td><td> </td><td class="rblock">     C.7.  Since draft-ietf-httpbis-p6-cache-05 . . . . . . . . . . . <span class="insert">34</span></td><td class="lineno" valign="top"></td></tr>
229      <tr><td class="lineno" valign="top"></td><td class="left">     C.8.  Since draft-ietf-httpbis-p6-cache-06 . . . . . . . . . . . 35</td><td> </td><td class="right">     C.8.  Since draft-ietf-httpbis-p6-cache-06 . . . . . . . . . . . 35</td><td class="lineno" valign="top"></td></tr>
230      <tr><td><a name="diff0019" /></td></tr>
231      <tr><td class="lineno" valign="top"></td><td class="lblock">     C.9.  Since draft-ietf-httpbis-p6-cache-07 . . . . . . . . . . . <span class="delete">36</span></td><td> </td><td class="rblock">     C.9.  Since draft-ietf-httpbis-p6-cache-07 . . . . . . . . . . . <span class="insert">35</span></td><td class="lineno" valign="top"></td></tr>
232      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">     C.10. Since draft-ietf-httpbis-p6-cache-08 . . . . . . . . . . . 35</span></td><td class="lineno" valign="top"></td></tr>
233      <tr><td class="lineno" valign="top"></td><td class="left">   Index  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36</td><td> </td><td class="right">   Index  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36</td><td class="lineno" valign="top"></td></tr>
234      <tr><td class="lineno" valign="top"></td><td class="left">   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 38</td><td> </td><td class="right">   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 38</td><td class="lineno" valign="top"></td></tr>
235      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
236      <tr><td class="lineno" valign="top"></td><td class="left">1.  Introduction</td><td> </td><td class="right">1.  Introduction</td><td class="lineno" valign="top"></td></tr>
237      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
238      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP is typically used for distributed information systems, where</td><td> </td><td class="right">   HTTP is typically used for distributed information systems, where</td><td class="lineno" valign="top"></td></tr>
239      <tr><td class="lineno" valign="top"></td><td class="left">   performance can be improved by the use of response caches.  This</td><td> </td><td class="right">   performance can be improved by the use of response caches.  This</td><td class="lineno" valign="top"></td></tr>
240      <tr><td class="lineno" valign="top"></td><td class="left">   document defines aspects of HTTP/1.1 related to caching and reusing</td><td> </td><td class="right">   document defines aspects of HTTP/1.1 related to caching and reusing</td><td class="lineno" valign="top"></td></tr>
241      <tr><td class="lineno" valign="top"></td><td class="left">   response messages.</td><td> </td><td class="right">   response messages.</td><td class="lineno" valign="top"></td></tr>
242      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
243      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
244      <tr bgcolor="gray" ><td></td><th><a name="part-l2" /><small>skipping to change at</small><em> page 8, line 5</em></th><th> </th><th><a name="part-r2" /><small>skipping to change at</small><em> page 8, line 5</em></th><td></td></tr>
245      <tr><td class="lineno" valign="top"></td><td class="left">     port          = &lt;port, defined in [Part1], Section 2.6&gt;</td><td> </td><td class="right">     port          = &lt;port, defined in [Part1], Section 2.6&gt;</td><td class="lineno" valign="top"></td></tr>
246      <tr><td class="lineno" valign="top"></td><td class="left">     pseudonym     = &lt;pseudonym, defined in [Part1], Section 9.9&gt;</td><td> </td><td class="right">     pseudonym     = &lt;pseudonym, defined in [Part1], Section 9.9&gt;</td><td class="lineno" valign="top"></td></tr>
247      <tr><td class="lineno" valign="top"></td><td class="left">     uri-host      = &lt;uri-host, defined in [Part1], Section 2.6&gt;</td><td> </td><td class="right">     uri-host      = &lt;uri-host, defined in [Part1], Section 2.6&gt;</td><td class="lineno" valign="top"></td></tr>
248      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
249      <tr><td class="lineno" valign="top"></td><td class="left">2.  Cache Operation</td><td> </td><td class="right">2.  Cache Operation</td><td class="lineno" valign="top"></td></tr>
250      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
251      <tr><td class="lineno" valign="top"></td><td class="left">2.1.  Response Cacheability</td><td> </td><td class="right">2.1.  Response Cacheability</td><td class="lineno" valign="top"></td></tr>
252      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
253      <tr><td class="lineno" valign="top"></td><td class="left">   A cache MUST NOT store a response to any request, unless:</td><td> </td><td class="right">   A cache MUST NOT store a response to any request, unless:</td><td class="lineno" valign="top"></td></tr>
254      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
255      <tr><td><a name="diff0020" /></td></tr>
256      <tr><td class="lineno" valign="top"></td><td class="lblock">   o  The request method is defined as being cacheable, and</td><td> </td><td class="rblock">   o  The request method is <span class="insert">understood by the cache and</span> defined as being</td><td class="lineno" valign="top"></td></tr>
257      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">      cacheable, and</td><td class="lineno" valign="top"></td></tr>
258      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">                                                                         </td><td class="lineno" valign="top"></td></tr>
259      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   <span class="insert">o  the response status code is understood by the cache, and</span></td><td class="lineno" valign="top"></td></tr>
260      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
261      <tr><td class="lineno" valign="top"></td><td class="left">   o  the "no-store" cache directive (see Section 3.2) does not appear</td><td> </td><td class="right">   o  the "no-store" cache directive (see Section 3.2) does not appear</td><td class="lineno" valign="top"></td></tr>
262      <tr><td class="lineno" valign="top"></td><td class="left">      in request or response headers, and</td><td> </td><td class="right">      in request or response headers, and</td><td class="lineno" valign="top"></td></tr>
263      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
264      <tr><td><a name="diff0021" /></td></tr>
265      <tr><td class="lineno" valign="top"></td><td class="lblock">   o  the "private" cache response directive (see Section 3.2 does not</td><td> </td><td class="rblock">   o  the "private" cache response directive (see Section 3.2<span class="insert">.2</span> does not</td><td class="lineno" valign="top"></td></tr>
266      <tr><td class="lineno" valign="top"></td><td class="left">      appear in the response, if the cache is shared, and</td><td> </td><td class="right">      appear in the response, if the cache is shared, and</td><td class="lineno" valign="top"></td></tr>
267      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
268      <tr><td class="lineno" valign="top"></td><td class="left">   o  the "Authorization" header (see Section 3.1 of [Part7]) does not</td><td> </td><td class="right">   o  the "Authorization" header (see Section 3.1 of [Part7]) does not</td><td class="lineno" valign="top"></td></tr>
269      <tr><td class="lineno" valign="top"></td><td class="left">      appear in the request, if the cache is shared (unless the "public"</td><td> </td><td class="right">      appear in the request, if the cache is shared (unless the "public"</td><td class="lineno" valign="top"></td></tr>
270      <tr><td class="lineno" valign="top"></td><td class="left">      directive is present; see Section 3.2), and</td><td> </td><td class="right">      directive is present; see Section 3.2), and</td><td class="lineno" valign="top"></td></tr>
271      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
272      <tr><td><a name="diff0022" /></td></tr>
273      <tr><td class="lineno" valign="top"></td><td class="lblock">   o  the cache <span class="delete">understands partial responses, if the</span> response is</td><td> </td><td class="rblock">   o  the <span class="insert">response either:</span></td><td class="lineno" valign="top"></td></tr>
274      <tr><td class="lineno" valign="top"></td><td class="lblock">      <span class="delete">partial</span> or <span class="delete">incomplete</span> (see Section 2.1.1).</td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
275      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      *  contains an Expires header (see Section 3.3), or</span></td><td class="lineno" valign="top"></td></tr>
276      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
277      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      *  contains a max-age response</span> cache <span class="insert">directive (see</span></td><td class="lineno" valign="top"></td></tr>
278      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">         Section 3.2.2), or</span></td><td class="lineno" valign="top"></td></tr>
279      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
280      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      *  contains a s-maxage</span> response <span class="insert">cache directive and the cache</span> is</td><td class="lineno" valign="top"></td></tr>
281      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">         <span class="insert">shared, or</span></td><td class="lineno" valign="top"></td></tr>
282      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
283      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      *  contains a Cache Control Extension (see Section 3.2.3) that</span></td><td class="lineno" valign="top"></td></tr>
284      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">         allows it to be cached, or</span></td><td class="lineno" valign="top"></td></tr>
285      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
286      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      *  has a status code that can be served with heuristic freshness</span></td><td class="lineno" valign="top"></td></tr>
287      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">         (see Section 2.3.1.1).</span></td><td class="lineno" valign="top"></td></tr>
288      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
289      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   In this context, a cache has "understood" a request method</span> or <span class="insert">a</span></td><td class="lineno" valign="top"></td></tr>
290      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   response status code if it recognises it and implements any cache-</span></td><td class="lineno" valign="top"></td></tr>
291      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   specific behaviour.  In particular, 206 Partial Content responses</span></td><td class="lineno" valign="top"></td></tr>
292      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   cannot be cached by an implementation that does not handle partial</span></td><td class="lineno" valign="top"></td></tr>
293      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   content</span> (see Section 2.1.1).</td><td class="lineno" valign="top"></td></tr>
294      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
295      <tr><td class="lineno" valign="top"></td><td class="left">   Note that in normal operation, most caches will not store a response</td><td> </td><td class="right">   Note that in normal operation, most caches will not store a response</td><td class="lineno" valign="top"></td></tr>
296      <tr><td class="lineno" valign="top"></td><td class="left">   that has neither a cache validator nor an explicit expiration time,</td><td> </td><td class="right">   that has neither a cache validator nor an explicit expiration time,</td><td class="lineno" valign="top"></td></tr>
297      <tr><td class="lineno" valign="top"></td><td class="left">   as such responses are not usually useful to store.  However, caches</td><td> </td><td class="right">   as such responses are not usually useful to store.  However, caches</td><td class="lineno" valign="top"></td></tr>
298      <tr><td class="lineno" valign="top"></td><td class="left">   are not prohibited from storing such responses.</td><td> </td><td class="right">   are not prohibited from storing such responses.</td><td class="lineno" valign="top"></td></tr>
299      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
300      <tr><td class="lineno" valign="top"></td><td class="left">2.1.1.  Storing Partial and Incomplete Responses</td><td> </td><td class="right">2.1.1.  Storing Partial and Incomplete Responses</td><td class="lineno" valign="top"></td></tr>
301      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
302      <tr><td class="lineno" valign="top"></td><td class="left">   A cache that receives an incomplete response (for example, with fewer</td><td> </td><td class="right">   A cache that receives an incomplete response (for example, with fewer</td><td class="lineno" valign="top"></td></tr>
303      <tr><td class="lineno" valign="top"></td><td class="left">   bytes of data than specified in a Content-Length header) can store</td><td> </td><td class="right">   bytes of data than specified in a Content-Length header) can store</td><td class="lineno" valign="top"></td></tr>
304      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
305      <tr bgcolor="gray" ><td></td><th><a name="part-l3" /><small>skipping to change at</small><em> page 9, line 25</em></th><th> </th><th><a name="part-r3" /><small>skipping to change at</small><em> page 9, line 47</em></th><td></td></tr>
306      <tr><td class="lineno" valign="top"></td><td class="left">      *  allowed to be served stale (see Section 2.3.3), or</td><td> </td><td class="right">      *  allowed to be served stale (see Section 2.3.3), or</td><td class="lineno" valign="top"></td></tr>
307      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
308      <tr><td class="lineno" valign="top"></td><td class="left">      *  successfully validated (see Section 2.4).</td><td> </td><td class="right">      *  successfully validated (see Section 2.4).</td><td class="lineno" valign="top"></td></tr>
309      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
310      <tr><td class="lineno" valign="top"></td><td class="left">   [[TODO-method-cacheability: define method cacheability for GET, HEAD</td><td> </td><td class="right">   [[TODO-method-cacheability: define method cacheability for GET, HEAD</td><td class="lineno" valign="top"></td></tr>
311      <tr><td class="lineno" valign="top"></td><td class="left">   and POST in p2-semantics.]]</td><td> </td><td class="right">   and POST in p2-semantics.]]</td><td class="lineno" valign="top"></td></tr>
312      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
313      <tr><td class="lineno" valign="top"></td><td class="left">   When a stored response is used to satisfy a request, caches MUST</td><td> </td><td class="right">   When a stored response is used to satisfy a request, caches MUST</td><td class="lineno" valign="top"></td></tr>
314      <tr><td class="lineno" valign="top"></td><td class="left">   include a single Age header field (Section 3.1) in the response with</td><td> </td><td class="right">   include a single Age header field (Section 3.1) in the response with</td><td class="lineno" valign="top"></td></tr>
315      <tr><td class="lineno" valign="top"></td><td class="left">   a value equal to the stored response's current_age; see</td><td> </td><td class="right">   a value equal to the stored response's current_age; see</td><td class="lineno" valign="top"></td></tr>
316      <tr><td><a name="diff0023" /></td></tr>
317      <tr><td class="lineno" valign="top"></td><td class="lblock">   Section 2.3.2. <span class="delete">[[anchor1: DISCUSS</span>: this currently includes</td><td> </td><td class="rblock">   Section 2.3.2. <span class="insert"> [[DISCUSS-includes-validated</span>: this currently includes</td><td class="lineno" valign="top"></td></tr>
318      <tr><td class="lineno" valign="top"></td><td class="left">   successfully validated responses.]]</td><td> </td><td class="right">   successfully validated responses.]]</td><td class="lineno" valign="top"></td></tr>
319      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
320      <tr><td class="lineno" valign="top"></td><td class="left">   Requests with methods that are unsafe (Section 7.1.1 of [Part2]) MUST</td><td> </td><td class="right">   Requests with methods that are unsafe (Section 7.1.1 of [Part2]) MUST</td><td class="lineno" valign="top"></td></tr>
321      <tr><td><a name="diff0024" /></td></tr>
322      <tr><td class="lineno" valign="top"></td><td class="lblock">   be written through the cache to the origin server; i.e., <span class="delete">A</span> cache must</td><td> </td><td class="rblock">   be written through the cache to the origin server; i.e., <span class="insert">a</span> cache must</td><td class="lineno" valign="top"></td></tr>
323      <tr><td class="lineno" valign="top"></td><td class="left">   not reply to such a request before having forwarded the request and</td><td> </td><td class="right">   not reply to such a request before having forwarded the request and</td><td class="lineno" valign="top"></td></tr>
324      <tr><td class="lineno" valign="top"></td><td class="left">   having received a corresponding response.</td><td> </td><td class="right">   having received a corresponding response.</td><td class="lineno" valign="top"></td></tr>
325      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
326      <tr><td class="lineno" valign="top"></td><td class="left">   Also, note that unsafe requests might invalidate already stored</td><td> </td><td class="right">   Also, note that unsafe requests might invalidate already stored</td><td class="lineno" valign="top"></td></tr>
327      <tr><td class="lineno" valign="top"></td><td class="left">   responses; see Section 2.5.</td><td> </td><td class="right">   responses; see Section 2.5.</td><td class="lineno" valign="top"></td></tr>
328      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
329      <tr><td class="lineno" valign="top"></td><td class="left">   Caches MUST use the most recent response (as determined by the Date</td><td> </td><td class="right">   Caches MUST use the most recent response (as determined by the Date</td><td class="lineno" valign="top"></td></tr>
330      <tr><td class="lineno" valign="top"></td><td class="left">   header) when more than one suitable response is stored.  They can</td><td> </td><td class="right">   header) when more than one suitable response is stored.  They can</td><td class="lineno" valign="top"></td></tr>
331      <tr><td class="lineno" valign="top"></td><td class="left">   also forward a request with "Cache-Control: max-age=0" or "Cache-</td><td> </td><td class="right">   also forward a request with "Cache-Control: max-age=0" or "Cache-</td><td class="lineno" valign="top"></td></tr>
332      <tr><td class="lineno" valign="top"></td><td class="left">   Control: no-cache" to disambiguate which response to use.</td><td> </td><td class="right">   Control: no-cache" to disambiguate which response to use.</td><td class="lineno" valign="top"></td></tr>
333      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
334      <tr bgcolor="gray" ><td></td><th><a name="part-l4" /><small>skipping to change at</small><em> page 10, line 12</em></th><th> </th><th><a name="part-r4" /><small>skipping to change at</small><em> page 10, line 34</em></th><td></td></tr>
335      <tr><td class="lineno" valign="top"></td><td class="left">   server to provide an explicit expiration time in the future, using</td><td> </td><td class="right">   server to provide an explicit expiration time in the future, using</td><td class="lineno" valign="top"></td></tr>
336      <tr><td class="lineno" valign="top"></td><td class="left">   either the Expires header (Section 3.3) or the max-age response cache</td><td> </td><td class="right">   either the Expires header (Section 3.3) or the max-age response cache</td><td class="lineno" valign="top"></td></tr>
337      <tr><td class="lineno" valign="top"></td><td class="left">   directive (Section 3.2.2).  Generally, origin servers will assign</td><td> </td><td class="right">   directive (Section 3.2.2).  Generally, origin servers will assign</td><td class="lineno" valign="top"></td></tr>
338      <tr><td class="lineno" valign="top"></td><td class="left">   future explicit expiration times to responses in the belief that the</td><td> </td><td class="right">   future explicit expiration times to responses in the belief that the</td><td class="lineno" valign="top"></td></tr>
339      <tr><td class="lineno" valign="top"></td><td class="left">   entity is not likely to change in a semantically significant way</td><td> </td><td class="right">   entity is not likely to change in a semantically significant way</td><td class="lineno" valign="top"></td></tr>
340      <tr><td class="lineno" valign="top"></td><td class="left">   before the expiration time is reached.</td><td> </td><td class="right">   before the expiration time is reached.</td><td class="lineno" valign="top"></td></tr>
341      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
342      <tr><td class="lineno" valign="top"></td><td class="left">   If an origin server wishes to force a cache to validate every</td><td> </td><td class="right">   If an origin server wishes to force a cache to validate every</td><td class="lineno" valign="top"></td></tr>
343      <tr><td class="lineno" valign="top"></td><td class="left">   request, it can assign an explicit expiration time in the past.  This</td><td> </td><td class="right">   request, it can assign an explicit expiration time in the past.  This</td><td class="lineno" valign="top"></td></tr>
344      <tr><td class="lineno" valign="top"></td><td class="left">   means that the response is always stale, so that caches should</td><td> </td><td class="right">   means that the response is always stale, so that caches should</td><td class="lineno" valign="top"></td></tr>
345      <tr><td><a name="diff0025" /></td></tr>
346      <tr><td class="lineno" valign="top"></td><td class="lblock">   validate it before using it for subsequent requests. <span class="delete">[[anchor2:</span> This</td><td> </td><td class="rblock">   validate it before using it for subsequent requests.  <span class="insert">[[TODO-</span></td><td class="lineno" valign="top"></td></tr>
347      <tr><td class="lineno" valign="top"></td><td class="lblock">   wording may cause confusion, because the response may still be served</td><td> </td><td class="rblock"><span class="insert">   response-stale:</span> This wording may cause confusion, because the</td><td class="lineno" valign="top"></td></tr>
348      <tr><td class="lineno" valign="top"></td><td class="lblock">   stale.]]</td><td> </td><td class="rblock">   response may still be served stale.]]</td><td class="lineno" valign="top"></td></tr>
349      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
350      <tr><td class="lineno" valign="top"></td><td class="left">   Since origin servers do not always provide explicit expiration times,</td><td> </td><td class="right">   Since origin servers do not always provide explicit expiration times,</td><td class="lineno" valign="top"></td></tr>
351      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP caches may also assign heuristic expiration times when they are</td><td> </td><td class="right">   HTTP caches may also assign heuristic expiration times when they are</td><td class="lineno" valign="top"></td></tr>
352      <tr><td class="lineno" valign="top"></td><td class="left">   not specified, employing algorithms that use other header values</td><td> </td><td class="right">   not specified, employing algorithms that use other header values</td><td class="lineno" valign="top"></td></tr>
353      <tr><td class="lineno" valign="top"></td><td class="left">   (such as the Last-Modified time) to estimate a plausible expiration</td><td> </td><td class="right">   (such as the Last-Modified time) to estimate a plausible expiration</td><td class="lineno" valign="top"></td></tr>
354      <tr><td class="lineno" valign="top"></td><td class="left">   time.  The HTTP/1.1 specification does not provide specific</td><td> </td><td class="right">   time.  The HTTP/1.1 specification does not provide specific</td><td class="lineno" valign="top"></td></tr>
355      <tr><td class="lineno" valign="top"></td><td class="left">   algorithms, but does impose worst-case constraints on their results.</td><td> </td><td class="right">   algorithms, but does impose worst-case constraints on their results.</td><td class="lineno" valign="top"></td></tr>
356      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
357      <tr><td class="lineno" valign="top"></td><td class="left">   The calculation to determine if a response is fresh is:</td><td> </td><td class="right">   The calculation to determine if a response is fresh is:</td><td class="lineno" valign="top"></td></tr>
358      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
359      <tr><td class="lineno" valign="top"></td><td class="left">      response_is_fresh = (freshness_lifetime &gt; current_age)</td><td> </td><td class="right">      response_is_fresh = (freshness_lifetime &gt; current_age)</td><td class="lineno" valign="top"></td></tr>
360      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
361      <tr><td class="lineno" valign="top"></td><td class="left">   The freshness_lifetime is defined in Section 2.3.1; the current_age</td><td> </td><td class="right">   The freshness_lifetime is defined in Section 2.3.1; the current_age</td><td class="lineno" valign="top"></td></tr>
362      <tr><td class="lineno" valign="top"></td><td class="left">   is defined in Section 2.3.2.</td><td> </td><td class="right">   is defined in Section 2.3.2.</td><td class="lineno" valign="top"></td></tr>
363      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
364      <tr><td class="lineno" valign="top"></td><td class="left">   Additionally, clients may need to influence freshness calculation.</td><td> </td><td class="right">   Additionally, clients may need to influence freshness calculation.</td><td class="lineno" valign="top"></td></tr>
365      <tr><td class="lineno" valign="top"></td><td class="left">   They can do this using several request cache directives, with the</td><td> </td><td class="right">   They can do this using several request cache directives, with the</td><td class="lineno" valign="top"></td></tr>
366      <tr><td class="lineno" valign="top"></td><td class="left">   effect of either increasing or loosening constraints on freshness.</td><td> </td><td class="right">   effect of either increasing or loosening constraints on freshness.</td><td class="lineno" valign="top"></td></tr>
367      <tr><td class="lineno" valign="top"></td><td class="left">   See Section 3.2.1.</td><td> </td><td class="right">   See Section 3.2.1.</td><td class="lineno" valign="top"></td></tr>
368      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
369      <tr><td><a name="diff0026" /></td></tr>
370      <tr><td class="lineno" valign="top"></td><td class="lblock">   <span class="delete">[[anchor3: ISSUE:</span> there are not requirements directly applying to</td><td> </td><td class="rblock">   <span class="insert">[[ISSUE-no-req-for-directives:</span> there are not requirements directly</td><td class="lineno" valign="top"></td></tr>
371      <tr><td class="lineno" valign="top"></td><td class="lblock">   cache-request-directives and freshness.]]</td><td> </td><td class="rblock">   applying to cache-request-directives and freshness.]]</td><td class="lineno" valign="top"></td></tr>
372      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
373      <tr><td class="lineno" valign="top"></td><td class="left">   Note that freshness applies only to cache operation; it cannot be</td><td> </td><td class="right">   Note that freshness applies only to cache operation; it cannot be</td><td class="lineno" valign="top"></td></tr>
374      <tr><td class="lineno" valign="top"></td><td class="left">   used to force a user agent to refresh its display or reload a</td><td> </td><td class="right">   used to force a user agent to refresh its display or reload a</td><td class="lineno" valign="top"></td></tr>
375      <tr><td class="lineno" valign="top"></td><td class="left">   resource.  See Section 4 for an explanation of the difference between</td><td> </td><td class="right">   resource.  See Section 4 for an explanation of the difference between</td><td class="lineno" valign="top"></td></tr>
376      <tr><td class="lineno" valign="top"></td><td class="left">   caches and history mechanisms.</td><td> </td><td class="right">   caches and history mechanisms.</td><td class="lineno" valign="top"></td></tr>
377      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
378      <tr><td class="lineno" valign="top"></td><td class="left">2.3.1.  Calculating Freshness Lifetime</td><td> </td><td class="right">2.3.1.  Calculating Freshness Lifetime</td><td class="lineno" valign="top"></td></tr>
379      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
380      <tr><td class="lineno" valign="top"></td><td class="left">   A cache can calculate the freshness lifetime (denoted as</td><td> </td><td class="right">   A cache can calculate the freshness lifetime (denoted as</td><td class="lineno" valign="top"></td></tr>
381      <tr><td class="lineno" valign="top"></td><td class="left">   freshness_lifetime) of a response by using the first match of:</td><td> </td><td class="right">   freshness_lifetime) of a response by using the first match of:</td><td class="lineno" valign="top"></td></tr>
382      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
383      <tr bgcolor="gray" ><td></td><th><a name="part-l5" /><small>skipping to change at</small><em> page 11, line 34</em></th><th> </th><th><a name="part-r5" /><small>skipping to change at</small><em> page 12, line 6</em></th><td></td></tr>
384      <tr><td class="lineno" valign="top"></td><td class="left">   When a heuristic is used to calculate freshness lifetime, the cache</td><td> </td><td class="right">   When a heuristic is used to calculate freshness lifetime, the cache</td><td class="lineno" valign="top"></td></tr>
385      <tr><td class="lineno" valign="top"></td><td class="left">   SHOULD attach a Warning header with a 113 warn-code to the response</td><td> </td><td class="right">   SHOULD attach a Warning header with a 113 warn-code to the response</td><td class="lineno" valign="top"></td></tr>
386      <tr><td class="lineno" valign="top"></td><td class="left">   if its current_age is more than 24 hours and such a warning is not</td><td> </td><td class="right">   if its current_age is more than 24 hours and such a warning is not</td><td class="lineno" valign="top"></td></tr>
387      <tr><td class="lineno" valign="top"></td><td class="left">   already present.</td><td> </td><td class="right">   already present.</td><td class="lineno" valign="top"></td></tr>
388      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
389      <tr><td class="lineno" valign="top"></td><td class="left">   Also, if the response has a Last-Modified header (Section 6.6 of</td><td> </td><td class="right">   Also, if the response has a Last-Modified header (Section 6.6 of</td><td class="lineno" valign="top"></td></tr>
390      <tr><td class="lineno" valign="top"></td><td class="left">   [Part4]), the heuristic expiration value SHOULD be no more than some</td><td> </td><td class="right">   [Part4]), the heuristic expiration value SHOULD be no more than some</td><td class="lineno" valign="top"></td></tr>
391      <tr><td class="lineno" valign="top"></td><td class="left">   fraction of the interval since that time.  A typical setting of this</td><td> </td><td class="right">   fraction of the interval since that time.  A typical setting of this</td><td class="lineno" valign="top"></td></tr>
392      <tr><td class="lineno" valign="top"></td><td class="left">   fraction might be 10%.</td><td> </td><td class="right">   fraction might be 10%.</td><td class="lineno" valign="top"></td></tr>
393      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
394      <tr><td><a name="diff0027" /></td></tr>
395      <tr><td class="lineno" valign="top"></td><td class="lblock">   <span class="delete">[[anchor4: REVIEW:</span> took away HTTP/1.0 query string heuristic</td><td> </td><td class="rblock">   <span class="insert">[[REVIEW-query-string-heuristics:</span> took away HTTP/1.0 query string</td><td class="lineno" valign="top"></td></tr>
396      <tr><td class="lineno" valign="top"></td><td class="lblock">   uncacheability.]]</td><td> </td><td class="rblock">   heuristic uncacheability.]]</td><td class="lineno" valign="top"></td></tr>
397      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
398      <tr><td class="lineno" valign="top"></td><td class="left">2.3.2.  Calculating Age</td><td> </td><td class="right">2.3.2.  Calculating Age</td><td class="lineno" valign="top"></td></tr>
399      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
400      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP/1.1 uses the Age response-header to convey the estimated age of</td><td> </td><td class="right">   HTTP/1.1 uses the Age response-header to convey the estimated age of</td><td class="lineno" valign="top"></td></tr>
401      <tr><td class="lineno" valign="top"></td><td class="left">   the response message when obtained from a cache.  The Age field value</td><td> </td><td class="right">   the response message when obtained from a cache.  The Age field value</td><td class="lineno" valign="top"></td></tr>
402      <tr><td class="lineno" valign="top"></td><td class="left">   is the cache's estimate of the amount of time since the response was</td><td> </td><td class="right">   is the cache's estimate of the amount of time since the response was</td><td class="lineno" valign="top"></td></tr>
403      <tr><td class="lineno" valign="top"></td><td class="left">   generated or validated by the origin server.  In essence, the Age</td><td> </td><td class="right">   generated or validated by the origin server.  In essence, the Age</td><td class="lineno" valign="top"></td></tr>
404      <tr><td class="lineno" valign="top"></td><td class="left">   value is the sum of the time that the response has been resident in</td><td> </td><td class="right">   value is the sum of the time that the response has been resident in</td><td class="lineno" valign="top"></td></tr>
405      <tr><td class="lineno" valign="top"></td><td class="left">   each of the caches along the path from the origin server, plus the</td><td> </td><td class="right">   each of the caches along the path from the origin server, plus the</td><td class="lineno" valign="top"></td></tr>
406      <tr><td class="lineno" valign="top"></td><td class="left">   amount of time it has been in transit along network paths.</td><td> </td><td class="right">   amount of time it has been in transit along network paths.</td><td class="lineno" valign="top"></td></tr>
407      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
408      <tr bgcolor="gray" ><td></td><th><a name="part-l6" /><small>skipping to change at</small><em> page 14, line 26</em></th><th> </th><th><a name="part-r6" /><small>skipping to change at</small><em> page 14, line 37</em></th><td></td></tr>
409      <tr><td class="lineno" valign="top"></td><td class="left">   contains only partial content, its entity-tag SHOULD NOT be included</td><td> </td><td class="right">   contains only partial content, its entity-tag SHOULD NOT be included</td><td class="lineno" valign="top"></td></tr>
410      <tr><td class="lineno" valign="top"></td><td class="left">   in the If-None-Match header field unless the request is for a range</td><td> </td><td class="right">   in the If-None-Match header field unless the request is for a range</td><td class="lineno" valign="top"></td></tr>
411      <tr><td class="lineno" valign="top"></td><td class="left">   that would be fully satisfied by that stored response.</td><td> </td><td class="right">   that would be fully satisfied by that stored response.</td><td class="lineno" valign="top"></td></tr>
412      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
413      <tr><td class="lineno" valign="top"></td><td class="left">   A 304 (Not Modified) response status code indicates that the stored</td><td> </td><td class="right">   A 304 (Not Modified) response status code indicates that the stored</td><td class="lineno" valign="top"></td></tr>
414      <tr><td class="lineno" valign="top"></td><td class="left">   response can be updated and reused; see Section 2.7.</td><td> </td><td class="right">   response can be updated and reused; see Section 2.7.</td><td class="lineno" valign="top"></td></tr>
415      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
416      <tr><td class="lineno" valign="top"></td><td class="left">   A full response (i.e., one with a response body) indicates that none</td><td> </td><td class="right">   A full response (i.e., one with a response body) indicates that none</td><td class="lineno" valign="top"></td></tr>
417      <tr><td class="lineno" valign="top"></td><td class="left">   of the stored responses nominated in the conditional request is</td><td> </td><td class="right">   of the stored responses nominated in the conditional request is</td><td class="lineno" valign="top"></td></tr>
418      <tr><td class="lineno" valign="top"></td><td class="left">   suitable.  Instead, the full response is used both to satisfy the</td><td> </td><td class="right">   suitable.  Instead, the full response is used both to satisfy the</td><td class="lineno" valign="top"></td></tr>
419      <tr><td><a name="diff0028" /></td></tr>
420      <tr><td class="lineno" valign="top"></td><td class="lblock">   request and replace the stored response. <span class="delete">[[anchor5:</span> Should there be a</td><td> </td><td class="rblock">   request and replace the stored response.  <span class="insert">[[TODO-req-missing:</span> Should</td><td class="lineno" valign="top"></td></tr>
421      <tr><td class="lineno" valign="top"></td><td class="lblock">   requirement here?]]</td><td> </td><td class="rblock">   there be a requirement here?]]</td><td class="lineno" valign="top"></td></tr>
422      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
423      <tr><td class="lineno" valign="top"></td><td class="left">   If a cache receives a 5xx response while attempting to validate a</td><td> </td><td class="right">   If a cache receives a 5xx response while attempting to validate a</td><td class="lineno" valign="top"></td></tr>
424      <tr><td class="lineno" valign="top"></td><td class="left">   response, it MAY either forward this response to the requesting</td><td> </td><td class="right">   response, it MAY either forward this response to the requesting</td><td class="lineno" valign="top"></td></tr>
425      <tr><td class="lineno" valign="top"></td><td class="left">   client, or act as if the server failed to respond.  In the latter</td><td> </td><td class="right">   client, or act as if the server failed to respond.  In the latter</td><td class="lineno" valign="top"></td></tr>
426      <tr><td class="lineno" valign="top"></td><td class="left">   case, it MAY return a previously stored response (see Section 2.3.3).</td><td> </td><td class="right">   case, it MAY return a previously stored response (see Section 2.3.3).</td><td class="lineno" valign="top"></td></tr>
427      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
428      <tr><td class="lineno" valign="top"></td><td class="left">2.5.  Request Methods that Invalidate</td><td> </td><td class="right">2.5.  Request Methods that Invalidate</td><td class="lineno" valign="top"></td></tr>
429      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
430      <tr><td class="lineno" valign="top"></td><td class="left">   Because unsafe methods (Section 7.1.1 of [Part2]) have the potential</td><td> </td><td class="right">   Because unsafe methods (Section 7.1.1 of [Part2]) have the potential</td><td class="lineno" valign="top"></td></tr>
431      <tr><td class="lineno" valign="top"></td><td class="left">   for changing state on the origin server, intervening caches can use</td><td> </td><td class="right">   for changing state on the origin server, intervening caches can use</td><td class="lineno" valign="top"></td></tr>
432      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
433      <tr bgcolor="gray" ><td></td><th><a name="part-l7" /><small>skipping to change at</small><em> page 15, line 7</em></th><th> </th><th><a name="part-r7" /><small>skipping to change at</small><em> page 15, line 18</em></th><td></td></tr>
434      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
435      <tr><td class="lineno" valign="top"></td><td class="left">   o  DELETE</td><td> </td><td class="right">   o  DELETE</td><td class="lineno" valign="top"></td></tr>
436      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
437      <tr><td class="lineno" valign="top"></td><td class="left">   o  POST</td><td> </td><td class="right">   o  POST</td><td class="lineno" valign="top"></td></tr>
438      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
439      <tr><td class="lineno" valign="top"></td><td class="left">   An invalidation based on a URI from a Location or Content-Location</td><td> </td><td class="right">   An invalidation based on a URI from a Location or Content-Location</td><td class="lineno" valign="top"></td></tr>
440      <tr><td class="lineno" valign="top"></td><td class="left">   header MUST NOT be performed if the host part of that URI differs</td><td> </td><td class="right">   header MUST NOT be performed if the host part of that URI differs</td><td class="lineno" valign="top"></td></tr>
441      <tr><td class="lineno" valign="top"></td><td class="left">   from the host part in the Request-URI.  This helps prevent denial of</td><td> </td><td class="right">   from the host part in the Request-URI.  This helps prevent denial of</td><td class="lineno" valign="top"></td></tr>
442      <tr><td class="lineno" valign="top"></td><td class="left">   service attacks.</td><td> </td><td class="right">   service attacks.</td><td class="lineno" valign="top"></td></tr>
443      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
444      <tr><td><a name="diff0029" /></td></tr>
445      <tr><td class="lineno" valign="top"></td><td class="lblock">   [[<span class="delete">anchor6: TODO</span>: "host part" needs to be specified better.]]</td><td> </td><td class="rblock">   [[<span class="insert">TODO-def-host-part</span>: "host part" needs to be specified better.]]</td><td class="lineno" valign="top"></td></tr>
446      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
447      <tr><td class="lineno" valign="top"></td><td class="left">   A cache that passes through requests for methods it does not</td><td> </td><td class="right">   A cache that passes through requests for methods it does not</td><td class="lineno" valign="top"></td></tr>
448      <tr><td class="lineno" valign="top"></td><td class="left">   understand SHOULD invalidate the Request-URI.</td><td> </td><td class="right">   understand SHOULD invalidate the Request-URI.</td><td class="lineno" valign="top"></td></tr>
449      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
450      <tr><td class="lineno" valign="top"></td><td class="left">   Here, "invalidate" means that the cache will either remove all stored</td><td> </td><td class="right">   Here, "invalidate" means that the cache will either remove all stored</td><td class="lineno" valign="top"></td></tr>
451      <tr><td class="lineno" valign="top"></td><td class="left">   responses related to the Request-URI, or will mark these as "invalid"</td><td> </td><td class="right">   responses related to the Request-URI, or will mark these as "invalid"</td><td class="lineno" valign="top"></td></tr>
452      <tr><td class="lineno" valign="top"></td><td class="left">   and in need of a mandatory validation before they can be returned in</td><td> </td><td class="right">   and in need of a mandatory validation before they can be returned in</td><td class="lineno" valign="top"></td></tr>
453      <tr><td class="lineno" valign="top"></td><td class="left">   response to a subsequent request.</td><td> </td><td class="right">   response to a subsequent request.</td><td class="lineno" valign="top"></td></tr>
454      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
455      <tr><td class="lineno" valign="top"></td><td class="left">   Note that this does not guarantee that all appropriate responses are</td><td> </td><td class="right">   Note that this does not guarantee that all appropriate responses are</td><td class="lineno" valign="top"></td></tr>
456      <tr><td class="lineno" valign="top"></td><td class="left">   invalidated.  For example, the request that caused the change at the</td><td> </td><td class="right">   invalidated.  For example, the request that caused the change at the</td><td class="lineno" valign="top"></td></tr>
457      <tr><td class="lineno" valign="top"></td><td class="left">   origin server might not have gone through the cache where a response</td><td> </td><td class="right">   origin server might not have gone through the cache where a response</td><td class="lineno" valign="top"></td></tr>
458      <tr><td class="lineno" valign="top"></td><td class="left">   is stored.</td><td> </td><td class="right">   is stored.</td><td class="lineno" valign="top"></td></tr>
459      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
460      <tr><td><a name="diff0030" /></td></tr>
461      <tr><td class="lineno" valign="top"></td><td class="lblock">   <span class="delete">[[anchor7: TODO:</span> specify that only successful (2xx, 3xx?) responses</td><td> </td><td class="rblock">   <span class="insert">[[TODO-spec-success-invalidate:</span> specify that only successful (2xx,</td><td class="lineno" valign="top"></td></tr>
462      <tr><td class="lineno" valign="top"></td><td class="lblock">   invalidate.]]</td><td> </td><td class="rblock">   3xx?) responses invalidate.]]</td><td class="lineno" valign="top"></td></tr>
463      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
464      <tr><td class="lineno" valign="top"></td><td class="left">2.6.  Caching Negotiated Responses</td><td> </td><td class="right">2.6.  Caching Negotiated Responses</td><td class="lineno" valign="top"></td></tr>
465      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
466      <tr><td class="lineno" valign="top"></td><td class="left">   When a cache receives a request that can be satisfied by a stored</td><td> </td><td class="right">   When a cache receives a request that can be satisfied by a stored</td><td class="lineno" valign="top"></td></tr>
467      <tr><td class="lineno" valign="top"></td><td class="left">   response that has a Vary header field (Section 3.5), it MUST NOT use</td><td> </td><td class="right">   response that has a Vary header field (Section 3.5), it MUST NOT use</td><td class="lineno" valign="top"></td></tr>
468      <tr><td class="lineno" valign="top"></td><td class="left">   that response unless all of the selecting request-headers nominated</td><td> </td><td class="right">   that response unless all of the selecting request-headers nominated</td><td class="lineno" valign="top"></td></tr>
469      <tr><td class="lineno" valign="top"></td><td class="left">   by the Vary header match in both the original request (i.e., that</td><td> </td><td class="right">   by the Vary header match in both the original request (i.e., that</td><td class="lineno" valign="top"></td></tr>
470      <tr><td class="lineno" valign="top"></td><td class="left">   associated with the stored response), and the presented request.</td><td> </td><td class="right">   associated with the stored response), and the presented request.</td><td class="lineno" valign="top"></td></tr>
471      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
472      <tr><td class="lineno" valign="top"></td><td class="left">   The selecting request-headers from two requests are defined to match</td><td> </td><td class="right">   The selecting request-headers from two requests are defined to match</td><td class="lineno" valign="top"></td></tr>
473      <tr><td><a name="diff0031" /></td></tr>
474      <tr><td class="lineno" valign="top"></td><td class="lblock">   if and only if <span class="delete">the selecting request-headers</span> in the first request can</td><td> </td><td class="rblock">   if and only if <span class="insert">those</span> in the first request can be transformed to <span class="insert">those</span></td><td class="lineno" valign="top"></td></tr>
475      <tr><td class="lineno" valign="top"></td><td class="lblock">   be transformed to <span class="delete">the selecting request-headers</span> in the second request</td><td> </td><td class="rblock">   in the second request by <span class="insert">applying any</span> of <span class="insert">the following:</span></td><td class="lineno" valign="top"></td></tr>
476      <tr><td class="lineno" valign="top"></td><td class="lblock">   by <span class="delete">adding or removing linear white space [[anchor8: [ref]]] at places</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
477      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   where this is allowed by the corresponding ABNF, and/or combining</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
478      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   multiple message-header fields with the same field name following the</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
479      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   rules about header fields in Section 3.2</span> of <span class="delete">[Part1].</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
480      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
481      <tr><td><a name="diff0032" /></td></tr>
482      <tr><td class="lineno" valign="top"></td><td class="lblock">   If a header field is absent from a request, it can only match another</td><td> </td><td class="rblock">   <span class="insert">o  adding or removing whitespace, where allowed in the header's</span></td><td class="lineno" valign="top"></td></tr>
483      <tr><td class="lineno" valign="top"></td><td class="lblock">   request if it is also absent there.</td><td> </td><td class="rblock"><span class="insert">      syntax</span></td><td class="lineno" valign="top"></td></tr>
484      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
485      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   o  combining multiple message-header fields with the same field name</span></td><td class="lineno" valign="top"></td></tr>
486      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      (see Section 3.2 of [Part1])</span></td><td class="lineno" valign="top"></td></tr>
487      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert"></span></td><td class="lineno" valign="top"></td></tr>
488      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">   o  normalizing both header values in a way that is known to have</span></td><td class="lineno" valign="top"></td></tr>
489      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      identical semantics, according to the header's specification</span></td><td class="lineno" valign="top"></td></tr>
490      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      (e.g., re-ordering field values when order is not significant;</span></td><td class="lineno" valign="top"></td></tr>
491      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      case-normalization, where values are defined to be case-</span></td><td class="lineno" valign="top"></td></tr>
492      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock"><span class="insert">      insensitive)</span></td><td class="lineno" valign="top"></td></tr>
493      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">                                                                         </td><td class="lineno" valign="top"></td></tr>
494      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   If <span class="insert">(after any normalisation that may take place)</span> a header field is</td><td class="lineno" valign="top"></td></tr>
495      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   absent from a request, it can only match another request if it is</td><td class="lineno" valign="top"></td></tr>
496      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   also absent there.</td><td class="lineno" valign="top"></td></tr>
497      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
498      <tr><td class="lineno" valign="top"></td><td class="left">   A Vary header field-value of "*" always fails to match, and</td><td> </td><td class="right">   A Vary header field-value of "*" always fails to match, and</td><td class="lineno" valign="top"></td></tr>
499      <tr><td class="lineno" valign="top"></td><td class="left">   subsequent requests to that resource can only be properly interpreted</td><td> </td><td class="right">   subsequent requests to that resource can only be properly interpreted</td><td class="lineno" valign="top"></td></tr>
500      <tr><td class="lineno" valign="top"></td><td class="left">   by the origin server.</td><td> </td><td class="right">   by the origin server.</td><td class="lineno" valign="top"></td></tr>
501      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
502      <tr><td class="lineno" valign="top"></td><td class="left">   The stored response with matching selecting request-headers is known</td><td> </td><td class="right">   The stored response with matching selecting request-headers is known</td><td class="lineno" valign="top"></td></tr>
503      <tr><td class="lineno" valign="top"></td><td class="left">   as the selected response.</td><td> </td><td class="right">   as the selected response.</td><td class="lineno" valign="top"></td></tr>
504      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
505      <tr><td class="lineno" valign="top"></td><td class="left">   If no selected response is available, the cache MAY forward the</td><td> </td><td class="right">   If no selected response is available, the cache MAY forward the</td><td class="lineno" valign="top"></td></tr>
506      <tr><td class="lineno" valign="top"></td><td class="left">   presented request to the origin server in a conditional request; see</td><td> </td><td class="right">   presented request to the origin server in a conditional request; see</td><td class="lineno" valign="top"></td></tr>
507      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
508      <tr bgcolor="gray" ><td></td><th><a name="part-l8" /><small>skipping to change at</small><em> page 16, line 16</em></th><th> </th><th><a name="part-r8" /><small>skipping to change at</small><em> page 16, line 38</em></th><td></td></tr>
509      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
510      <tr><td class="lineno" valign="top"></td><td class="left">2.7.  Combining Responses</td><td> </td><td class="right">2.7.  Combining Responses</td><td class="lineno" valign="top"></td></tr>
511      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
512      <tr><td class="lineno" valign="top"></td><td class="left">   When a cache receives a 304 (Not Modified) response or a 206 (Partial</td><td> </td><td class="right">   When a cache receives a 304 (Not Modified) response or a 206 (Partial</td><td class="lineno" valign="top"></td></tr>
513      <tr><td class="lineno" valign="top"></td><td class="left">   Content) response (in this section, the "new" response"), it needs to</td><td> </td><td class="right">   Content) response (in this section, the "new" response"), it needs to</td><td class="lineno" valign="top"></td></tr>
514      <tr><td class="lineno" valign="top"></td><td class="left">   created an updated response by combining the stored response with the</td><td> </td><td class="right">   created an updated response by combining the stored response with the</td><td class="lineno" valign="top"></td></tr>
515      <tr><td class="lineno" valign="top"></td><td class="left">   new one, so that the updated response can be used to satisfy the</td><td> </td><td class="right">   new one, so that the updated response can be used to satisfy the</td><td class="lineno" valign="top"></td></tr>
516      <tr><td class="lineno" valign="top"></td><td class="left">   request.</td><td> </td><td class="right">   request.</td><td class="lineno" valign="top"></td></tr>
517      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
518      <tr><td class="lineno" valign="top"></td><td class="left">   If the new response contains an ETag, it identifies the stored</td><td> </td><td class="right">   If the new response contains an ETag, it identifies the stored</td><td class="lineno" valign="top"></td></tr>
519      <tr><td><a name="diff0033" /></td></tr>
520      <tr><td class="lineno" valign="top"></td><td class="lblock">   response to use. <span class="delete">[[anchor9:</span> may need language about <span class="delete">Content-Location</span></td><td> </td><td class="rblock">   response to use.  <span class="insert">[[TODO-mention-CL:</span> may need language about <span class="insert">Content-</span></td><td class="lineno" valign="top"></td></tr>
521      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   here]][[anchor10:</span> cover case where INM with multiple etags was sent]]</td><td> </td><td class="rblock"><span class="insert">   Location here]][[TODO-inm-mult-etags:</span> cover case where INM with</td><td class="lineno" valign="top"></td></tr>
522      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">   multiple etags was sent]]</td><td class="lineno" valign="top"></td></tr>
523      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
524      <tr><td class="lineno" valign="top"></td><td class="left">   If the status code is 206 (partial content), both the stored and new</td><td> </td><td class="right">   If the status code is 206 (partial content), both the stored and new</td><td class="lineno" valign="top"></td></tr>
525      <tr><td class="lineno" valign="top"></td><td class="left">   responses MUST have validators, and those validators MUST match using</td><td> </td><td class="right">   responses MUST have validators, and those validators MUST match using</td><td class="lineno" valign="top"></td></tr>
526      <tr><td class="lineno" valign="top"></td><td class="left">   the strong comparison function (see Section 4 of [Part4]).</td><td> </td><td class="right">   the strong comparison function (see Section 4 of [Part4]).</td><td class="lineno" valign="top"></td></tr>
527      <tr><td class="lineno" valign="top"></td><td class="left">   Otherwise, the responses MUST NOT be combined.</td><td> </td><td class="right">   Otherwise, the responses MUST NOT be combined.</td><td class="lineno" valign="top"></td></tr>
528      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
529      <tr><td class="lineno" valign="top"></td><td class="left">   The stored response headers are used as those of the updated</td><td> </td><td class="right">   The stored response headers are used as those of the updated</td><td class="lineno" valign="top"></td></tr>
530      <tr><td class="lineno" valign="top"></td><td class="left">   response, except that</td><td> </td><td class="right">   response, except that</td><td class="lineno" valign="top"></td></tr>
531      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
532      <tr><td class="lineno" valign="top"></td><td class="left">   o  any stored Warning headers with warn-code 1xx (see Section 3.6)</td><td> </td><td class="right">   o  any stored Warning headers with warn-code 1xx (see Section 3.6)</td><td class="lineno" valign="top"></td></tr>
533      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
534      <tr bgcolor="gray" ><td></td><th><a name="part-l9" /><small>skipping to change at</small><em> page 16, line 40</em></th><th> </th><th><a name="part-r9" /><small>skipping to change at</small><em> page 17, line 15</em></th><td></td></tr>
535      <tr><td class="lineno" valign="top"></td><td class="left">   o  any stored Warning headers with warn-code 2xx MUST be retained in</td><td> </td><td class="right">   o  any stored Warning headers with warn-code 2xx MUST be retained in</td><td class="lineno" valign="top"></td></tr>
536      <tr><td class="lineno" valign="top"></td><td class="left">      the stored response and the updated response.</td><td> </td><td class="right">      the stored response and the updated response.</td><td class="lineno" valign="top"></td></tr>
537      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
538      <tr><td class="lineno" valign="top"></td><td class="left">   o  any headers provided in the new response MUST replace the</td><td> </td><td class="right">   o  any headers provided in the new response MUST replace the</td><td class="lineno" valign="top"></td></tr>
539      <tr><td class="lineno" valign="top"></td><td class="left">      corresponding headers from the stored response.</td><td> </td><td class="right">      corresponding headers from the stored response.</td><td class="lineno" valign="top"></td></tr>
540      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
541      <tr><td class="lineno" valign="top"></td><td class="left">   If a header field-name in the new response matches more than one</td><td> </td><td class="right">   If a header field-name in the new response matches more than one</td><td class="lineno" valign="top"></td></tr>
542      <tr><td class="lineno" valign="top"></td><td class="left">   header in the stored response, all such stored headers MUST be</td><td> </td><td class="right">   header in the stored response, all such stored headers MUST be</td><td class="lineno" valign="top"></td></tr>
543      <tr><td class="lineno" valign="top"></td><td class="left">   replaced.</td><td> </td><td class="right">   replaced.</td><td class="lineno" valign="top"></td></tr>
544      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
545      <tr><td><a name="diff0034" /></td></tr>
546      <tr><td class="lineno" valign="top"></td><td class="lblock">   The updated response can [[<span class="delete">[[anchor11: requirement?]]</span>]] be used to</td><td> </td><td class="rblock">   The updated response can [[<span class="insert">TODO-is-req: requirement?</span>]] be used to</td><td class="lineno" valign="top"></td></tr>
547      <tr><td class="lineno" valign="top"></td><td class="left">   replace the stored response in cache.  In the case of a 206 response,</td><td> </td><td class="right">   replace the stored response in cache.  In the case of a 206 response,</td><td class="lineno" valign="top"></td></tr>
548      <tr><td class="lineno" valign="top"></td><td class="left">   the combined entity-body MAY be stored.</td><td> </td><td class="right">   the combined entity-body MAY be stored.</td><td class="lineno" valign="top"></td></tr>
549      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
550      <tr><td><a name="diff0035" /></td></tr>
551      <tr><td class="lineno" valign="top"></td><td class="lblock">   [[<span class="delete">anchor12: ISSUE</span>: discuss how to handle HEAD updates]]</td><td> </td><td class="rblock">   [[<span class="insert">ISSUE-how-head</span>: discuss how to handle HEAD updates]]</td><td class="lineno" valign="top"></td></tr>
552      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
553      <tr><td class="lineno" valign="top"></td><td class="left">3.  Header Field Definitions</td><td> </td><td class="right">3.  Header Field Definitions</td><td class="lineno" valign="top"></td></tr>
554      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
555      <tr><td class="lineno" valign="top"></td><td class="left">   This section defines the syntax and semantics of HTTP/1.1 header</td><td> </td><td class="right">   This section defines the syntax and semantics of HTTP/1.1 header</td><td class="lineno" valign="top"></td></tr>
556      <tr><td class="lineno" valign="top"></td><td class="left">   fields related to caching.</td><td> </td><td class="right">   fields related to caching.</td><td class="lineno" valign="top"></td></tr>
557      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
558      <tr><td class="lineno" valign="top"></td><td class="left">   For entity-header fields, both sender and recipient refer to either</td><td> </td><td class="right">   For entity-header fields, both sender and recipient refer to either</td><td class="lineno" valign="top"></td></tr>
559      <tr><td class="lineno" valign="top"></td><td class="left">   the client or the server, depending on who sends and who receives the</td><td> </td><td class="right">   the client or the server, depending on who sends and who receives the</td><td class="lineno" valign="top"></td></tr>
560      <tr><td class="lineno" valign="top"></td><td class="left">   entity.</td><td> </td><td class="right">   entity.</td><td class="lineno" valign="top"></td></tr>
561      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
562      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
563      <tr bgcolor="gray" ><td></td><th><a name="part-l10" /><small>skipping to change at</small><em> page 19, line 13</em></th><th> </th><th><a name="part-r10" /><small>skipping to change at</small><em> page 19, line 32</em></th><td></td></tr>
564      <tr><td class="lineno" valign="top"></td><td class="left">      client is not willing to accept a stale response.</td><td> </td><td class="right">      client is not willing to accept a stale response.</td><td class="lineno" valign="top"></td></tr>
565      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
566      <tr><td class="lineno" valign="top"></td><td class="left">   max-stale</td><td> </td><td class="right">   max-stale</td><td class="lineno" valign="top"></td></tr>
567      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
568      <tr><td class="lineno" valign="top"></td><td class="left">      The max-stale request directive indicates that the client is</td><td> </td><td class="right">      The max-stale request directive indicates that the client is</td><td class="lineno" valign="top"></td></tr>
569      <tr><td class="lineno" valign="top"></td><td class="left">      willing to accept a response that has exceeded its expiration</td><td> </td><td class="right">      willing to accept a response that has exceeded its expiration</td><td class="lineno" valign="top"></td></tr>
570      <tr><td class="lineno" valign="top"></td><td class="left">      time.  If max-stale is assigned a value, then the client is</td><td> </td><td class="right">      time.  If max-stale is assigned a value, then the client is</td><td class="lineno" valign="top"></td></tr>
571      <tr><td class="lineno" valign="top"></td><td class="left">      willing to accept a response that has exceeded its expiration time</td><td> </td><td class="right">      willing to accept a response that has exceeded its expiration time</td><td class="lineno" valign="top"></td></tr>
572      <tr><td class="lineno" valign="top"></td><td class="left">      by no more than the specified number of seconds.  If no value is</td><td> </td><td class="right">      by no more than the specified number of seconds.  If no value is</td><td class="lineno" valign="top"></td></tr>
573      <tr><td class="lineno" valign="top"></td><td class="left">      assigned to max-stale, then the client is willing to accept a</td><td> </td><td class="right">      assigned to max-stale, then the client is willing to accept a</td><td class="lineno" valign="top"></td></tr>
574      <tr><td><a name="diff0036" /></td></tr>
575      <tr><td class="lineno" valign="top"></td><td class="lblock">      stale response of any age. <span class="delete">[[anchor13:</span> of any staleness? --mnot]]</td><td> </td><td class="rblock">      stale response of any age.  <span class="insert">[[TODO-staleness:</span> of any staleness?</td><td class="lineno" valign="top"></td></tr>
576      <tr><td class="lineno" valign="top"></td><td class="lblock"></td><td> </td><td class="rblock">      --mnot]]</td><td class="lineno" valign="top"></td></tr>
577      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
578      <tr><td class="lineno" valign="top"></td><td class="left">   min-fresh</td><td> </td><td class="right">   min-fresh</td><td class="lineno" valign="top"></td></tr>
579      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
580      <tr><td class="lineno" valign="top"></td><td class="left">      The min-fresh request directive indicates that the client is</td><td> </td><td class="right">      The min-fresh request directive indicates that the client is</td><td class="lineno" valign="top"></td></tr>
581      <tr><td class="lineno" valign="top"></td><td class="left">      willing to accept a response whose freshness lifetime is no less</td><td> </td><td class="right">      willing to accept a response whose freshness lifetime is no less</td><td class="lineno" valign="top"></td></tr>
582      <tr><td class="lineno" valign="top"></td><td class="left">      than its current age plus the specified time in seconds.  That is,</td><td> </td><td class="right">      than its current age plus the specified time in seconds.  That is,</td><td class="lineno" valign="top"></td></tr>
583      <tr><td class="lineno" valign="top"></td><td class="left">      the client wants a response that will still be fresh for at least</td><td> </td><td class="right">      the client wants a response that will still be fresh for at least</td><td class="lineno" valign="top"></td></tr>
584      <tr><td class="lineno" valign="top"></td><td class="left">      the specified number of seconds.</td><td> </td><td class="right">      the specified number of seconds.</td><td class="lineno" valign="top"></td></tr>
585      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
586      <tr><td class="lineno" valign="top"></td><td class="left">   no-transform</td><td> </td><td class="right">   no-transform</td><td class="lineno" valign="top"></td></tr>
587      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
588      <tr bgcolor="gray" ><td></td><th><a name="part-l11" /><small>skipping to change at</small><em> page 20, line 42</em></th><th> </th><th><a name="part-r11" /><small>skipping to change at</small><em> page 20, line 50</em></th><td></td></tr>
589      <tr><td class="lineno" valign="top"></td><td class="left">      If the private response directive specifies one or more field-</td><td> </td><td class="right">      If the private response directive specifies one or more field-</td><td class="lineno" valign="top"></td></tr>
590      <tr><td class="lineno" valign="top"></td><td class="left">      names, this requirement is limited to the field-values associated</td><td> </td><td class="right">      names, this requirement is limited to the field-values associated</td><td class="lineno" valign="top"></td></tr>
591      <tr><td class="lineno" valign="top"></td><td class="left">      with the listed response headers.  That is, the specified field-</td><td> </td><td class="right">      with the listed response headers.  That is, the specified field-</td><td class="lineno" valign="top"></td></tr>
592      <tr><td class="lineno" valign="top"></td><td class="left">      names(s) MUST NOT be stored by a shared cache, whereas the</td><td> </td><td class="right">      names(s) MUST NOT be stored by a shared cache, whereas the</td><td class="lineno" valign="top"></td></tr>
593      <tr><td class="lineno" valign="top"></td><td class="left">      remainder of the response message MAY be.</td><td> </td><td class="right">      remainder of the response message MAY be.</td><td class="lineno" valign="top"></td></tr>
594      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
595      <tr><td class="lineno" valign="top"></td><td class="left">      Note: This usage of the word private only controls where the</td><td> </td><td class="right">      Note: This usage of the word private only controls where the</td><td class="lineno" valign="top"></td></tr>
596      <tr><td class="lineno" valign="top"></td><td class="left">      response may be stored, and cannot ensure the privacy of the</td><td> </td><td class="right">      response may be stored, and cannot ensure the privacy of the</td><td class="lineno" valign="top"></td></tr>
597      <tr><td class="lineno" valign="top"></td><td class="left">      message content.  Also, private response directives with field-</td><td> </td><td class="right">      message content.  Also, private response directives with field-</td><td class="lineno" valign="top"></td></tr>
598      <tr><td class="lineno" valign="top"></td><td class="left">      names are often handled by implementations as if an unqualified</td><td> </td><td class="right">      names are often handled by implementations as if an unqualified</td><td class="lineno" valign="top"></td></tr>
599      <tr><td><a name="diff0037" /></td></tr>
600      <tr><td class="lineno" valign="top"></td><td class="lblock">      private directive was rec<span class="delete">ie</span>ved; i.e., the special handling for the</td><td> </td><td class="rblock">      private directive was rec<span class="insert">ei</span>ved; i.e., the special handling for the</td><td class="lineno" valign="top"></td></tr>
601      <tr><td class="lineno" valign="top"></td><td class="left">      qualified form is not widely implemented.</td><td> </td><td class="right">      qualified form is not widely implemented.</td><td class="lineno" valign="top"></td></tr>
602      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
603      <tr><td class="lineno" valign="top"></td><td class="left">   no-cache</td><td> </td><td class="right">   no-cache</td><td class="lineno" valign="top"></td></tr>
604      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
605      <tr><td class="lineno" valign="top"></td><td class="left">      The no-cache response directive indicates that the response MUST</td><td> </td><td class="right">      The no-cache response directive indicates that the response MUST</td><td class="lineno" valign="top"></td></tr>
606      <tr><td class="lineno" valign="top"></td><td class="left">      NOT be used to satisfy a subsequent request without successful</td><td> </td><td class="right">      NOT be used to satisfy a subsequent request without successful</td><td class="lineno" valign="top"></td></tr>
607      <tr><td class="lineno" valign="top"></td><td class="left">      validation on the origin server.  This allows an origin server to</td><td> </td><td class="right">      validation on the origin server.  This allows an origin server to</td><td class="lineno" valign="top"></td></tr>
608      <tr><td class="lineno" valign="top"></td><td class="left">      prevent caching even by caches that have been configured to return</td><td> </td><td class="right">      prevent caching even by caches that have been configured to return</td><td class="lineno" valign="top"></td></tr>
609      <tr><td class="lineno" valign="top"></td><td class="left">      stale responses.</td><td> </td><td class="right">      stale responses.</td><td class="lineno" valign="top"></td></tr>
610      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
611      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
612      <tr bgcolor="gray" ><td></td><th><a name="part-l12" /><small>skipping to change at</small><em> page 21, line 17</em></th><th> </th><th><a name="part-r12" /><small>skipping to change at</small><em> page 21, line 25</em></th><td></td></tr>
613      <tr><td class="lineno" valign="top"></td><td class="left">      with the listed response headers.  That is, the specified field-</td><td> </td><td class="right">      with the listed response headers.  That is, the specified field-</td><td class="lineno" valign="top"></td></tr>
614      <tr><td class="lineno" valign="top"></td><td class="left">      name(s) MUST NOT be sent in the response to a subsequent request</td><td> </td><td class="right">      name(s) MUST NOT be sent in the response to a subsequent request</td><td class="lineno" valign="top"></td></tr>
615      <tr><td class="lineno" valign="top"></td><td class="left">      without successful validation on the origin server.  This allows</td><td> </td><td class="right">      without successful validation on the origin server.  This allows</td><td class="lineno" valign="top"></td></tr>
616      <tr><td class="lineno" valign="top"></td><td class="left">      an origin server to prevent the re-use of certain header fields in</td><td> </td><td class="right">      an origin server to prevent the re-use of certain header fields in</td><td class="lineno" valign="top"></td></tr>
617      <tr><td class="lineno" valign="top"></td><td class="left">      a response, while still allowing caching of the rest of the</td><td> </td><td class="right">      a response, while still allowing caching of the rest of the</td><td class="lineno" valign="top"></td></tr>
618      <tr><td class="lineno" valign="top"></td><td class="left">      response.</td><td> </td><td class="right">      response.</td><td class="lineno" valign="top"></td></tr>
619      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
620      <tr><td class="lineno" valign="top"></td><td class="left">      Note: Most HTTP/1.0 caches will not recognize or obey this</td><td> </td><td class="right">      Note: Most HTTP/1.0 caches will not recognize or obey this</td><td class="lineno" valign="top"></td></tr>
621      <tr><td class="lineno" valign="top"></td><td class="left">      directive.  Also, no-cache response directives with field-names</td><td> </td><td class="right">      directive.  Also, no-cache response directives with field-names</td><td class="lineno" valign="top"></td></tr>
622      <tr><td class="lineno" valign="top"></td><td class="left">      are often handled by implementations as if an unqualified no-cache</td><td> </td><td class="right">      are often handled by implementations as if an unqualified no-cache</td><td class="lineno" valign="top"></td></tr>
623      <tr><td><a name="diff0038" /></td></tr>
624      <tr><td class="lineno" valign="top"></td><td class="lblock">      directive was rec<span class="delete">ie</span>ved; i.e., the special handling for the</td><td> </td><td class="rblock">      directive was rec<span class="insert">ei</span>ved; i.e., the special handling for the</td><td class="lineno" valign="top"></td></tr>
625      <tr><td class="lineno" valign="top"></td><td class="left">      qualified form is not widely implemented.</td><td> </td><td class="right">      qualified form is not widely implemented.</td><td class="lineno" valign="top"></td></tr>
626      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
627      <tr><td class="lineno" valign="top"></td><td class="left">   no-store</td><td> </td><td class="right">   no-store</td><td class="lineno" valign="top"></td></tr>
628      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
629      <tr><td class="lineno" valign="top"></td><td class="left">      The no-store response directive indicates that a cache MUST NOT</td><td> </td><td class="right">      The no-store response directive indicates that a cache MUST NOT</td><td class="lineno" valign="top"></td></tr>
630      <tr><td class="lineno" valign="top"></td><td class="left">      store any part of either the immediate request or response.  This</td><td> </td><td class="right">      store any part of either the immediate request or response.  This</td><td class="lineno" valign="top"></td></tr>
631      <tr><td class="lineno" valign="top"></td><td class="left">      directive applies to both non-shared and shared caches.  "MUST NOT</td><td> </td><td class="right">      directive applies to both non-shared and shared caches.  "MUST NOT</td><td class="lineno" valign="top"></td></tr>
632      <tr><td class="lineno" valign="top"></td><td class="left">      store" in this context means that the cache MUST NOT intentionally</td><td> </td><td class="right">      store" in this context means that the cache MUST NOT intentionally</td><td class="lineno" valign="top"></td></tr>
633      <tr><td class="lineno" valign="top"></td><td class="left">      store the information in non-volatile storage, and MUST make a</td><td> </td><td class="right">      store the information in non-volatile storage, and MUST make a</td><td class="lineno" valign="top"></td></tr>
634      <tr><td class="lineno" valign="top"></td><td class="left">      best-effort attempt to remove the information from volatile</td><td> </td><td class="right">      best-effort attempt to remove the information from volatile</td><td class="lineno" valign="top"></td></tr>
635      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
636      <tr bgcolor="gray" ><td></td><th><a name="part-l13" /><small>skipping to change at</small><em> page 23, line 41</em></th><th> </th><th><a name="part-r13" /><small>skipping to change at</small><em> page 24, line 4</em></th><td></td></tr>
637      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
638      <tr><td class="lineno" valign="top"></td><td class="left">   The field-value is an absolute date and time as defined by HTTP-date</td><td> </td><td class="right">   The field-value is an absolute date and time as defined by HTTP-date</td><td class="lineno" valign="top"></td></tr>
639      <tr><td class="lineno" valign="top"></td><td class="left">   in Section 6.1 of [Part1]; it MUST be sent in rfc1123-date format.</td><td> </td><td class="right">   in Section 6.1 of [Part1]; it MUST be sent in rfc1123-date format.</td><td class="lineno" valign="top"></td></tr>
640      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
641      <tr><td class="lineno" valign="top"></td><td class="left">     Expires   = "Expires" ":" OWS Expires-v</td><td> </td><td class="right">     Expires   = "Expires" ":" OWS Expires-v</td><td class="lineno" valign="top"></td></tr>
642      <tr><td class="lineno" valign="top"></td><td class="left">     Expires-v = HTTP-date</td><td> </td><td class="right">     Expires-v = HTTP-date</td><td class="lineno" valign="top"></td></tr>
643      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
644      <tr><td class="lineno" valign="top"></td><td class="left">   For example</td><td> </td><td class="right">   For example</td><td class="lineno" valign="top"></td></tr>
645      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
646      <tr><td class="lineno" valign="top"></td><td class="left">     Expires: Thu, 01 Dec 1994 16:00:00 GMT</td><td> </td><td class="right">     Expires: Thu, 01 Dec 1994 16:00:00 GMT</td><td class="lineno" valign="top"></td></tr>
647      <tr><td><a name="diff0039" /></td></tr>
648      <tr><td class="lineno" valign="top"></td><td class="lblock">                                                                         </td><td> </td><td class="rblock">      Note: <span class="insert">If</span> a response includes a Cache-Control field with the max-</td><td class="lineno" valign="top"></td></tr>
649      <tr><td class="lineno" valign="top"></td><td class="lblock">      Note: <span class="delete">if</span> a response includes a Cache-Control field with the max-</td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
650      <tr><td class="lineno" valign="top"></td><td class="left">      age directive (see Section 3.2.2), that directive overrides the</td><td> </td><td class="right">      age directive (see Section 3.2.2), that directive overrides the</td><td class="lineno" valign="top"></td></tr>
651      <tr><td class="lineno" valign="top"></td><td class="left">      Expires field.  Likewise, the s-maxage directive overrides Expires</td><td> </td><td class="right">      Expires field.  Likewise, the s-maxage directive overrides Expires</td><td class="lineno" valign="top"></td></tr>
652      <tr><td class="lineno" valign="top"></td><td class="left">      in shared caches.</td><td> </td><td class="right">      in shared caches.</td><td class="lineno" valign="top"></td></tr>
653      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
654      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP/1.1 servers SHOULD NOT send Expires dates more than one year in</td><td> </td><td class="right">   HTTP/1.1 servers SHOULD NOT send Expires dates more than one year in</td><td class="lineno" valign="top"></td></tr>
655      <tr><td class="lineno" valign="top"></td><td class="left">   the future.</td><td> </td><td class="right">   the future.</td><td class="lineno" valign="top"></td></tr>
656      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
657      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP/1.1 clients and caches MUST treat other invalid date formats,</td><td> </td><td class="right">   HTTP/1.1 clients and caches MUST treat other invalid date formats,</td><td class="lineno" valign="top"></td></tr>
658      <tr><td class="lineno" valign="top"></td><td class="left">   especially including the value "0", as in the past (i.e., "already</td><td> </td><td class="right">   especially including the value "0", as in the past (i.e., "already</td><td class="lineno" valign="top"></td></tr>
659      <tr><td class="lineno" valign="top"></td><td class="left">   expired").</td><td> </td><td class="right">   expired").</td><td class="lineno" valign="top"></td></tr>
660      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
661      <tr bgcolor="gray" ><td></td><th><a name="part-l14" /><small>skipping to change at</small><em> page 24, line 29</em></th><th> </th><th><a name="part-r14" /><small>skipping to change at</small><em> page 24, line 39</em></th><td></td></tr>
662      <tr><td class="lineno" valign="top"></td><td class="left">   When the no-cache directive is present in a request message, an</td><td> </td><td class="right">   When the no-cache directive is present in a request message, an</td><td class="lineno" valign="top"></td></tr>
663      <tr><td class="lineno" valign="top"></td><td class="left">   application SHOULD forward the request toward the origin server even</td><td> </td><td class="right">   application SHOULD forward the request toward the origin server even</td><td class="lineno" valign="top"></td></tr>
664      <tr><td class="lineno" valign="top"></td><td class="left">   if it has a cached copy of what is being requested.  This pragma</td><td> </td><td class="right">   if it has a cached copy of what is being requested.  This pragma</td><td class="lineno" valign="top"></td></tr>
665      <tr><td class="lineno" valign="top"></td><td class="left">   directive has the same semantics as the no-cache response directive</td><td> </td><td class="right">   directive has the same semantics as the no-cache response directive</td><td class="lineno" valign="top"></td></tr>
666      <tr><td class="lineno" valign="top"></td><td class="left">   (see Section 3.2.2) and is defined here for backward compatibility</td><td> </td><td class="right">   (see Section 3.2.2) and is defined here for backward compatibility</td><td class="lineno" valign="top"></td></tr>
667      <tr><td class="lineno" valign="top"></td><td class="left">   with HTTP/1.0.  Clients SHOULD include both header fields when a no-</td><td> </td><td class="right">   with HTTP/1.0.  Clients SHOULD include both header fields when a no-</td><td class="lineno" valign="top"></td></tr>
668      <tr><td class="lineno" valign="top"></td><td class="left">   cache request is sent to a server not known to be HTTP/1.1 compliant.</td><td> </td><td class="right">   cache request is sent to a server not known to be HTTP/1.1 compliant.</td><td class="lineno" valign="top"></td></tr>
669      <tr><td class="lineno" valign="top"></td><td class="left">   HTTP/1.1 caches SHOULD treat "Pragma: no-cache" as if the client had</td><td> </td><td class="right">   HTTP/1.1 caches SHOULD treat "Pragma: no-cache" as if the client had</td><td class="lineno" valign="top"></td></tr>
670      <tr><td class="lineno" valign="top"></td><td class="left">   sent "Cache-Control: no-cache".</td><td> </td><td class="right">   sent "Cache-Control: no-cache".</td><td class="lineno" valign="top"></td></tr>
671      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
672      <tr><td><a name="diff0040" /></td></tr>
673      <tr><td class="lineno" valign="top"></td><td class="lblock">      Note: <span class="delete">b</span>ecause the meaning of "Pragma: no-cache" as a response-</td><td> </td><td class="rblock">      Note: <span class="insert">B</span>ecause the meaning of "Pragma: no-cache" as a response-</td><td class="lineno" valign="top"></td></tr>
674      <tr><td class="lineno" valign="top"></td><td class="left">      header field is not actually specified, it does not provide a</td><td> </td><td class="right">      header field is not actually specified, it does not provide a</td><td class="lineno" valign="top"></td></tr>
675      <tr><td class="lineno" valign="top"></td><td class="left">      reliable replacement for "Cache-Control: no-cache" in a response.</td><td> </td><td class="right">      reliable replacement for "Cache-Control: no-cache" in a response.</td><td class="lineno" valign="top"></td></tr>
676      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
677      <tr><td class="lineno" valign="top"></td><td class="left">   This mechanism is deprecated; no new Pragma directives will be</td><td> </td><td class="right">   This mechanism is deprecated; no new Pragma directives will be</td><td class="lineno" valign="top"></td></tr>
678      <tr><td class="lineno" valign="top"></td><td class="left">   defined in HTTP.</td><td> </td><td class="right">   defined in HTTP.</td><td class="lineno" valign="top"></td></tr>
679      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
680      <tr><td class="lineno" valign="top"></td><td class="left">3.5.  Vary</td><td> </td><td class="right">3.5.  Vary</td><td class="lineno" valign="top"></td></tr>
681      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
682      <tr><td class="lineno" valign="top"></td><td class="left">   The "Vary" response-header field conveys the set of request-header</td><td> </td><td class="right">   The "Vary" response-header field conveys the set of request-header</td><td class="lineno" valign="top"></td></tr>
683      <tr><td class="lineno" valign="top"></td><td class="left">   fields that were used to select the representation.</td><td> </td><td class="right">   fields that were used to select the representation.</td><td class="lineno" valign="top"></td></tr>
684      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
685      <tr><td class="lineno" valign="top"></td><td class="left">   Caches use this information, in part, to determine whether a stored</td><td> </td><td class="right">   Caches use this information, in part, to determine whether a stored</td><td class="lineno" valign="top"></td></tr>
686      <tr><td><a name="diff0041" /></td></tr>
687      <tr><td class="lineno" valign="top"></td><td class="lblock">   response can be used to satis<span class="delete">d</span>y a given request; see Section 2.6.</td><td> </td><td class="rblock">   response can be used to satis<span class="insert">f</span>y a given request; see Section 2.6.</td><td class="lineno" valign="top"></td></tr>
688      <tr><td class="lineno" valign="top"></td><td class="left">   determines, while the response is fresh, whether a cache is permitted</td><td> </td><td class="right">   determines, while the response is fresh, whether a cache is permitted</td><td class="lineno" valign="top"></td></tr>
689      <tr><td class="lineno" valign="top"></td><td class="left">   to use the response to reply to a subsequent request without</td><td> </td><td class="right">   to use the response to reply to a subsequent request without</td><td class="lineno" valign="top"></td></tr>
690      <tr><td class="lineno" valign="top"></td><td class="left">   validation; see Section 2.6.</td><td> </td><td class="right">   validation; see Section 2.6.</td><td class="lineno" valign="top"></td></tr>
691      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
692      <tr><td class="lineno" valign="top"></td><td class="left">   In uncacheable or stale responses, the Vary field value advises the</td><td> </td><td class="right">   In uncacheable or stale responses, the Vary field value advises the</td><td class="lineno" valign="top"></td></tr>
693      <tr><td class="lineno" valign="top"></td><td class="left">   user agent about the criteria that were used to select the</td><td> </td><td class="right">   user agent about the criteria that were used to select the</td><td class="lineno" valign="top"></td></tr>
694      <tr><td class="lineno" valign="top"></td><td class="left">   representation.</td><td> </td><td class="right">   representation.</td><td class="lineno" valign="top"></td></tr>
695      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
696      <tr><td class="lineno" valign="top"></td><td class="left">     Vary   = "Vary" ":" OWS Vary-v</td><td> </td><td class="right">     Vary   = "Vary" ":" OWS Vary-v</td><td class="lineno" valign="top"></td></tr>
697      <tr><td class="lineno" valign="top"></td><td class="left">     Vary-v = "*" / 1#field-name</td><td> </td><td class="right">     Vary-v = "*" / 1#field-name</td><td class="lineno" valign="top"></td></tr>
698      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
699      <tr bgcolor="gray" ><td></td><th><a name="part-l15" /><small>skipping to change at</small><em> page 25, line 41</em></th><th> </th><th><a name="part-r15" /><small>skipping to change at</small><em> page 25, line 51</em></th><td></td></tr>
700      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
701      <tr><td class="lineno" valign="top"></td><td class="left">   The "Warning" general-header field is used to carry additional</td><td> </td><td class="right">   The "Warning" general-header field is used to carry additional</td><td class="lineno" valign="top"></td></tr>
702      <tr><td class="lineno" valign="top"></td><td class="left">   information about the status or transformation of a message that</td><td> </td><td class="right">   information about the status or transformation of a message that</td><td class="lineno" valign="top"></td></tr>
703      <tr><td class="lineno" valign="top"></td><td class="left">   might not be reflected in the message.  This information is typically</td><td> </td><td class="right">   might not be reflected in the message.  This information is typically</td><td class="lineno" valign="top"></td></tr>
704      <tr><td class="lineno" valign="top"></td><td class="left">   used to warn about possible incorrectness introduced by caching</td><td> </td><td class="right">   used to warn about possible incorrectness introduced by caching</td><td class="lineno" valign="top"></td></tr>
705      <tr><td class="lineno" valign="top"></td><td class="left">   operations or transformations applied to the entity body of the</td><td> </td><td class="right">   operations or transformations applied to the entity body of the</td><td class="lineno" valign="top"></td></tr>
706      <tr><td class="lineno" valign="top"></td><td class="left">   message.</td><td> </td><td class="right">   message.</td><td class="lineno" valign="top"></td></tr>
707      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
708      <tr><td class="lineno" valign="top"></td><td class="left">   Warnings can be used for other purposes, both cache-related and</td><td> </td><td class="right">   Warnings can be used for other purposes, both cache-related and</td><td class="lineno" valign="top"></td></tr>
709      <tr><td class="lineno" valign="top"></td><td class="left">   otherwise.  The use of a warning, rather than an error status code,</td><td> </td><td class="right">   otherwise.  The use of a warning, rather than an error status code,</td><td class="lineno" valign="top"></td></tr>
710      <tr><td><a name="diff0042" /></td></tr>
711      <tr><td class="lineno" valign="top"></td><td class="lblock">   distinguish these responses from true failures.</td><td> </td><td class="rblock">   distinguish<span class="insert">es</span> these responses from true failures.</td><td class="lineno" valign="top"></td></tr>
712      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
713      <tr><td class="lineno" valign="top"></td><td class="left">   Warning headers can in general be applied to any message, however</td><td> </td><td class="right">   Warning headers can in general be applied to any message, however</td><td class="lineno" valign="top"></td></tr>
714      <tr><td class="lineno" valign="top"></td><td class="left">   some warn-codes are specific to caches and can only be applied to</td><td> </td><td class="right">   some warn-codes are specific to caches and can only be applied to</td><td class="lineno" valign="top"></td></tr>
715      <tr><td class="lineno" valign="top"></td><td class="left">   response messages.</td><td> </td><td class="right">   response messages.</td><td class="lineno" valign="top"></td></tr>
716      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
717      <tr><td class="lineno" valign="top"></td><td class="left">     Warning    = "Warning" ":" OWS Warning-v</td><td> </td><td class="right">     Warning    = "Warning" ":" OWS Warning-v</td><td class="lineno" valign="top"></td></tr>
718      <tr><td class="lineno" valign="top"></td><td class="left">     Warning-v  = 1#warning-value</td><td> </td><td class="right">     Warning-v  = 1#warning-value</td><td class="lineno" valign="top"></td></tr>
719      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
720      <tr><td class="lineno" valign="top"></td><td class="left">     warning-value = warn-code SP warn-agent SP warn-text</td><td> </td><td class="right">     warning-value = warn-code SP warn-agent SP warn-text</td><td class="lineno" valign="top"></td></tr>
721      <tr><td class="lineno" valign="top"></td><td class="left">                                           [SP warn-date]</td><td> </td><td class="right">                                           [SP warn-date]</td><td class="lineno" valign="top"></td></tr>
722      <tr><td class="lineno"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno"></td></tr>
723      <tr bgcolor="gray" ><td></td><th><a name="part-l16" /><small>skipping to change at</small><em> page 28, line 12</em></th><th> </th><th><a name="part-r16" /><small>skipping to change at</small><em> page 28, line 17</em></th><td></td></tr>
724      <tr><td class="lineno" valign="top"></td><td class="left">      The warning text can include arbitrary information to be presented</td><td> </td><td class="right">      The warning text can include arbitrary information to be presented</td><td class="lineno" valign="top"></td></tr>
725      <tr><td class="lineno" valign="top"></td><td class="left">      to a human user, or logged.  A system receiving this warning MUST</td><td> </td><td class="right">      to a human user, or logged.  A system receiving this warning MUST</td><td class="lineno" valign="top"></td></tr>
726      <tr><td class="lineno" valign="top"></td><td class="left">      NOT take any automated action.</td><td> </td><td class="right">      NOT take any automated action.</td><td class="lineno" valign="top"></td></tr>
727      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
728      <tr><td class="lineno" valign="top"></td><td class="left">4.  History Lists</td><td> </td><td class="right">4.  History Lists</td><td class="lineno" valign="top"></td></tr>
729      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
730      <tr><td class="lineno" valign="top"></td><td class="left">   User agents often have history mechanisms, such as "Back" buttons and</td><td> </td><td class="right">   User agents often have history mechanisms, such as "Back" buttons and</td><td class="lineno" valign="top"></td></tr>
731      <tr><td class="lineno" valign="top"></td><td class="left">   history lists, that can be used to redisplay an entity retrieved</td><td> </td><td class="right">   history lists, that can be used to redisplay an entity retrieved</td><td class="lineno" valign="top"></td></tr>
732      <tr><td class="lineno" valign="top"></td><td class="left">   earlier in a session.</td><td> </td><td class="right">   earlier in a session.</td><td class="lineno" valign="top"></td></tr>
733      <tr><td class="lineno" valign="top"></td><td class="left"></td><td> </td><td class="right"></td><td class="lineno" valign="top"></td></tr>
734      <tr><td><a name="diff0043" /></td></tr>
735      <tr><td class="lineno" valign="top"></td><td class="lblock">   <span class="delete">History mechanisms and caches are different.  In particular history</span></td><td> </td><td class="rblock">   <span class="insert">The freshness model (Section 2.3)</span> does not <span class="insert">necessarily</span> apply to</td><td class="lineno" valign="top"></td></tr>
736      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   mechanisms SHOULD NOT try to show a correct view of the current state</span></td><td> </td><td class="rblock">   history mechanisms.  <span class="insert">I.e.,</span> a history mechanism <span class="insert">can</span> display <span class="insert">a previous</span></td><td class="lineno" valign="top"></td></tr>
737      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   of a resource.  Rather, a history mechanism is meant to show exactly</span></td><td> </td><td class="rblock"><span class="insert">   representation</span> even if <span class="insert">it</span> has <span class="insert">expired.</span></td><td class="lineno" valign="top"></td></tr>
738      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   what the user saw at the time when the resource was retrieved.</span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
739      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete"></span></td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
740      <tr><td class="lineno" valign="top"></td><td class="lblock"><span class="delete">   By default, an expiration time</span> does not apply to history mechanisms.</td><td> </td><td class="rblock"></td><td class="lineno" valign="top"></td></tr>
741      <tr><td