Changeset 1400 for draft-ietf-httpbis

Timestamp:

Aug 22, 2011, 12:53:05 AM (8 years ago)

Author:

mnot@…

Message:

Clarify one-year limit on Expires; addresses #290

Location:

draft-ietf-httpbis/latest

Files:

• p6-cache.html (modified) (7 diffs)
• p6-cache.xml (modified) (3 diffs)

draft-ietf-httpbis/latest/p6-cache.html

@@ -362 +362 @@
   } 
   @bottom-center {
-       content: "Expires February 10, 2012"; 
+       content: "Expires February 23, 2012"; 
   } 
   @bottom-right {
@@ -408 +408 @@
       <meta name="dct.creator" content="Reschke, J. F.">
       <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p6-cache-latest">
-      <meta name="dct.issued" scheme="ISO8601" content="2011-08-09">
+      <meta name="dct.issued" scheme="ISO8601" content="2011-08-22">
       <meta name="dct.replaces" content="urn:ietf:rfc:2616">
       <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 6 of the seven-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34; and, taken together, obsoletes RFC 2616. Part 6 defines requirements on HTTP caches and the associated header fields that control cache behavior or indicate cacheable response messages.">
@@ -434 +434 @@
             </tr>
             <tr>
-               <td class="left">Expires: February 10, 2012</td>
+               <td class="left">Expires: February 23, 2012</td>
                <td class="right">J. Mogul</td>
             </tr>
@@ -495 +495 @@
             <tr>
                <td class="left"></td>
-               <td class="right">August 9, 2011</td>
+               <td class="right">August 22, 2011</td>
             </tr>
          </tbody>
@@ -525 +525 @@
          in progress”.
       </p>
-      <p>This Internet-Draft will expire on February 10, 2012.</p>
+      <p>This Internet-Draft will expire on February 23, 2012.</p>
       <h1><a id="rfc.copyrightnotice" href="#rfc.copyrightnotice">Copyright Notice</a></h1>
       <p>Copyright © 2011 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
@@ -1359 +1359 @@
 </pre><div id="rfc.figure.u.14"></div> 
       <p>For example</p>  <pre class="text">  Expires: Thu, 01 Dec 1994 16:00:00 GMT
-</pre><div class="note" id="rfc.section.3.3.p.6"> 
+</pre><p id="rfc.section.3.3.p.6">A cache <em class="bcp14">MUST</em> treat other invalid date formats, especially including the value "0", as in the past (i.e., "already expired").
+      </p>
+      <div class="note" id="rfc.section.3.3.p.7"> 
          <p> <b>Note:</b> If a response includes a Cache-Control field with the max-age directive (see <a href="#cache-response-directive" title="Response Cache-Control Directives">Section&nbsp;3.2.2</a>), that directive overrides the Expires field. Likewise, the s-maxage directive overrides Expires in shared caches.
          </p> 
       </div>
-      <p id="rfc.section.3.3.p.7">A server <em class="bcp14">SHOULD NOT</em> send Expires dates more than one year in the future.
-      </p>
-      <p id="rfc.section.3.3.p.8">A cache <em class="bcp14">MUST</em> treat other invalid date formats, especially including the value "0", as in the past (i.e., "already expired").
+      <p id="rfc.section.3.3.p.8">Historically, HTTP required the Expires field-value to be no more than a year in the future. While longer freshness lifetimes
+         are no longer prohibited, extremely large values have been demonstrated to cause problems (e.g., clock overflows due to use
+         of 32-bit integers for time values), and most caches will evict a response far sooner than that. Therefore, senders ought
+         not produce them.
       </p>
       <div id="rfc.iref.p.5"></div>
@@ -2041 +2044 @@
       </ul>
       <h2 id="rfc.section.C.17"><a href="#rfc.section.C.17">C.17</a>&nbsp;<a id="changes.since.15" href="#changes.since.15">Since draft-ietf-httpbis-p6-cache-15</a></h2>
-      <p id="rfc.section.C.17.p.1">None yet.</p>
+      <p id="rfc.section.C.17.p.1">Closed issues: </p>
+      <ul>
+         <li> &lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/290">http://tools.ietf.org/wg/httpbis/trac/ticket/290</a>&gt;: "Motivate one-year limit for Expires"
+         </li>
+      </ul>
       <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
       <p class="noprint"><a href="#rfc.index.A">A</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.E">E</a> <a href="#rfc.index.F">F</a> <a href="#rfc.index.G">G</a> <a href="#rfc.index.H">H</a> <a href="#rfc.index.M">M</a> <a href="#rfc.index.N">N</a> <a href="#rfc.index.O">O</a> <a href="#rfc.index.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.S">S</a> <a href="#rfc.index.V">V</a> <a href="#rfc.index.W">W</a> 

draft-ietf-httpbis/latest/p6-cache.xml

@@ -1603 +1603 @@
   Expires: Thu, 01 Dec 1994 16:00:00 GMT
 </artwork></figure>
+<t>
+   A cache &MUST; treat other invalid date formats,
+   especially including the value "0", as in the past (i.e., "already
+   expired").
+</t>
 <x:note>
    <t>
@@ -1612 +1617 @@
 </x:note>
 <t>
-   A server &SHOULD-NOT; send Expires dates more than one year in the
-   future.
-</t>
-<t>
-   A cache &MUST; treat other invalid date formats,
-   especially including the value "0", as in the past (i.e., "already
-   expired").
+   Historically, HTTP required the Expires field-value to be no more than a 
+   year in the future. While longer freshness lifetimes are no longer 
+   prohibited, extremely large values have been demonstrated to cause 
+   problems (e.g., clock overflows due to use of 32-bit integers for 
+   time values), and most caches will evict a response far sooner than 
+   that. Therefore, senders ought not produce them.
 </t>
 </section>
@@ -2857 +2861 @@
 <section title="Since draft-ietf-httpbis-p6-cache-15" anchor="changes.since.15">
 <t>
-  None yet.
+  Closed issues:
+  <list style="symbols">
+    <t>
+      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/290"/>:
+      "Motivate one-year limit for Expires"
+    </t>
+  </list>
 </t>
 </section>