Changeset 1860 for draft-ietf-httpbis

Timestamp:

Sep 3, 2012, 4:03:33 PM (7 years ago)

Author:

fielding@…

Message:

(editorial) move Vary to p2 because it is generated by origin servers and not limited to caching

Location:

draft-ietf-httpbis/latest

Files:

• p2-semantics.html (modified) (55 diffs)
• p2-semantics.xml (modified) (16 diffs)
• p4-conditional.html (modified) (9 diffs)
• p4-conditional.xml (modified) (4 diffs)
• p5-range.html (modified) (8 diffs)
• p5-range.xml (modified) (2 diffs)
• p6-cache.html (modified) (35 diffs)
• p6-cache.xml (modified) (8 diffs)

draft-ietf-httpbis/latest/p2-semantics.html

@@ -719 +719 @@
                <li><a href="#rfc.section.8.2">8.2</a>&nbsp;&nbsp;&nbsp;<a href="#response.cache.related">Cache-related</a><ul>
                      <li><a href="#rfc.section.8.2.1">8.2.1</a>&nbsp;&nbsp;&nbsp;<a href="#header.date">Date</a></li>
+                     <li><a href="#rfc.section.8.2.2">8.2.2</a>&nbsp;&nbsp;&nbsp;<a href="#header.vary">Vary</a></li>
                   </ul>
                </li>
@@ -1171 +1172 @@
          </p> 
       </div>
-      <p id="rfc.section.3.5.1.p.7">The <a href="p6-cache.html#header.vary" class="smpl">Vary</a> header field (<a href="p6-cache.html#header.vary" title="Vary">Section 7.5</a> of <a href="#Part6" id="rfc.xref.Part6.2"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) can be used to express the parameters the server uses to select a representation that is subject to proactive negotiation.
+      <p id="rfc.section.3.5.1.p.7">The <a href="#header.vary" class="smpl">Vary</a> header field (<a href="#header.vary" id="rfc.xref.header.vary.1" title="Vary">Section&nbsp;8.2.2</a>) can be used to express the parameters the server uses to select a representation that is subject to proactive negotiation.
       </p>
       <h3 id="rfc.section.3.5.2"><a href="#rfc.section.3.5.2">3.5.2</a>&nbsp;<a id="reactive.negotiation" href="#reactive.negotiation">Reactive Negotiation</a></h3>
@@ -1359 +1360 @@
          are defined to be cacheable. In general, safe methods that do not depend on a current or authoritative response are cacheable,
          though the overwhelming majority of caches only support GET and HEAD. HTTP requirements for cache behavior and cacheable responses
-         are defined in <a href="#Part6" id="rfc.xref.Part6.3"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>.
+         are defined in <a href="#Part6" id="rfc.xref.Part6.2"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>.
       </p>
       <h2 id="rfc.section.5.3"><a href="#rfc.section.5.3">5.3</a>&nbsp;<a id="method.definitions" href="#method.definitions">Method Definitions</a></h2>
@@ -1379 +1380 @@
          to reject the request.
       </p>
-      <p id="rfc.section.5.3.1.p.6">The response to a GET request is cacheable and <em class="bcp14">MAY</em> be used to satisfy subsequent GET and HEAD requests (see <a href="#Part6" id="rfc.xref.Part6.4"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+      <p id="rfc.section.5.3.1.p.6">The response to a GET request is cacheable and <em class="bcp14">MAY</em> be used to satisfy subsequent GET and HEAD requests (see <a href="#Part6" id="rfc.xref.Part6.3"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
       </p>
       <p id="rfc.section.5.3.1.p.7">See <a href="#encoding.sensitive.information.in.uris" title="Encoding Sensitive Information in URIs">Section&nbsp;11.2</a> for security considerations when used for forms.
@@ -1390 +1391 @@
          hypertext links for validity, accessibility, and recent modification.
       </p>
-      <p id="rfc.section.5.3.2.p.2">The response to a HEAD request is cacheable and <em class="bcp14">MAY</em> be used to satisfy a subsequent HEAD request. It also has potential side effects on previously stored responses to GET; see <a href="p6-cache.html#head.effects" title="Updating Caches with HEAD Responses">Section 5</a> of <a href="#Part6" id="rfc.xref.Part6.5"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>.
+      <p id="rfc.section.5.3.2.p.2">The response to a HEAD request is cacheable and <em class="bcp14">MAY</em> be used to satisfy a subsequent HEAD request. It also has potential side effects on previously stored responses to GET; see <a href="p6-cache.html#head.effects" title="Updating Caches with HEAD Responses">Section 5</a> of <a href="#Part6" id="rfc.xref.Part6.4"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>.
       </p>
       <p id="rfc.section.5.3.2.p.3">Bodies on HEAD requests have no defined semantics. Note that sending a body on a HEAD request might cause some existing implementations
@@ -1415 +1416 @@
       <p id="rfc.section.5.3.3.p.4">If a resource has been created on the origin server, the response <em class="bcp14">SHOULD</em> be <a href="#status.201" class="smpl">201 (Created)</a> and contain a representation which describes the status of the request and refers to the new resource, and a <a href="#header.location" class="smpl">Location</a> header field (see <a href="#header.location" id="rfc.xref.header.location.1" title="Location">Section&nbsp;8.1.1</a>).
       </p>
-      <p id="rfc.section.5.3.3.p.5">Responses to POST requests are only cacheable when they include explicit freshness information (see <a href="p6-cache.html#calculating.freshness.lifetime" title="Calculating Freshness Lifetime">Section 4.1.1</a> of <a href="#Part6" id="rfc.xref.Part6.6"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>). A cached POST response with a <a href="#header.content-location" class="smpl">Content-Location</a> header field (see <a href="#header.content-location" id="rfc.xref.header.content-location.2" title="Content-Location">Section&nbsp;3.2.4</a>) whose value is the effective Request URI <em class="bcp14">MAY</em> be used to satisfy subsequent GET and HEAD requests.
+      <p id="rfc.section.5.3.3.p.5">Responses to POST requests are only cacheable when they include explicit freshness information (see <a href="p6-cache.html#calculating.freshness.lifetime" title="Calculating Freshness Lifetime">Section 4.1.1</a> of <a href="#Part6" id="rfc.xref.Part6.5"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>). A cached POST response with a <a href="#header.content-location" class="smpl">Content-Location</a> header field (see <a href="#header.content-location" id="rfc.xref.header.content-location.2" title="Content-Location">Section&nbsp;3.2.4</a>) whose value is the effective Request URI <em class="bcp14">MAY</em> be used to satisfy subsequent GET and HEAD requests.
       </p>
       <p id="rfc.section.5.3.3.p.6">Note that POST caching is not widely implemented. However, the <a href="#status.303" class="smpl">303 (See Other)</a> response can be used to direct the user agent to retrieve a cacheable representation of the resource.
@@ -1481 +1482 @@
       </p>
       <p id="rfc.section.5.3.4.p.11">Responses to the PUT method are not cacheable. If a PUT request passes through a cache that has one or more stored responses
-         for the effective request URI, those stored responses will be invalidated (see <a href="p6-cache.html#invalidation.after.updates.or.deletions" title="Request Methods that Invalidate">Section 6</a> of <a href="#Part6" id="rfc.xref.Part6.7"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+         for the effective request URI, those stored responses will be invalidated (see <a href="p6-cache.html#invalidation.after.updates.or.deletions" title="Request Methods that Invalidate">Section 6</a> of <a href="#Part6" id="rfc.xref.Part6.6"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
       </p>
       <h3 id="rfc.section.5.3.5"><a href="#rfc.section.5.3.5">5.3.5</a>&nbsp;<a id="DELETE" href="#DELETE">DELETE</a></h3>
@@ -1497 +1498 @@
       </p>
       <p id="rfc.section.5.3.5.p.4">Responses to the DELETE method are not cacheable. If a DELETE request passes through a cache that has one or more stored responses
-         for the effective request URI, those stored responses will be invalidated (see <a href="p6-cache.html#invalidation.after.updates.or.deletions" title="Request Methods that Invalidate">Section 6</a> of <a href="#Part6" id="rfc.xref.Part6.8"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+         for the effective request URI, those stored responses will be invalidated (see <a href="p6-cache.html#invalidation.after.updates.or.deletions" title="Request Methods that Invalidate">Section 6</a> of <a href="#Part6" id="rfc.xref.Part6.7"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
       </p>
       <div id="rfc.iref.c.7"></div>
@@ -2380 +2381 @@
          <dd>a representation containing the request message as received by the end server.</dd>
       </dl>
-      <p id="rfc.section.7.3.1.p.2">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.9"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 200 responses.
+      <p id="rfc.section.7.3.1.p.2">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.8"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 200 responses.
       </p>
       <div id="rfc.iref.80"></div>
@@ -2410 +2411 @@
       <div id="rfc.iref.s.10"></div>
       <h3 id="rfc.section.7.3.4"><a href="#rfc.section.7.3.4">7.3.4</a>&nbsp;<a id="status.203" href="#status.203">203 Non-Authoritative Information</a></h3>
-      <p id="rfc.section.7.3.4.p.1">The representation in the response has been transformed or otherwise modified by a transforming proxy (<a href="p1-messaging.html#intermediaries" title="Intermediaries">Section 2.3</a> of <a href="#Part1" id="rfc.xref.Part1.20"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>). Note that the behavior of transforming intermediaries is controlled by the no-transform Cache-Control directive (<a href="p6-cache.html#header.cache-control" title="Cache-Control">Section 7.2</a> of <a href="#Part6" id="rfc.xref.Part6.10"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+      <p id="rfc.section.7.3.4.p.1">The representation in the response has been transformed or otherwise modified by a transforming proxy (<a href="p1-messaging.html#intermediaries" title="Intermediaries">Section 2.3</a> of <a href="#Part1" id="rfc.xref.Part1.20"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>). Note that the behavior of transforming intermediaries is controlled by the no-transform Cache-Control directive (<a href="p6-cache.html#header.cache-control" title="Cache-Control">Section 7.2</a> of <a href="#Part6" id="rfc.xref.Part6.9"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
       </p>
       <p id="rfc.section.7.3.4.p.2">This status code is only appropriate when the response status code would have been <a href="#status.200" class="smpl">200 (OK)</a> otherwise. When the status code before transformation would have been different, the 214 Transformation Applied warn-code
-         (<a href="p6-cache.html#header.warning" title="Warning">Section 7.6</a> of <a href="#Part6" id="rfc.xref.Part6.11"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) is appropriate.
-      </p>
-      <p id="rfc.section.7.3.4.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.12"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 203 responses.
+         (<a href="p6-cache.html#header.warning" title="Warning">Section 7.5</a> of <a href="#Part6" id="rfc.xref.Part6.10"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) is appropriate.
+      </p>
+      <p id="rfc.section.7.3.4.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.11"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 203 responses.
       </p>
       <div id="rfc.iref.83"></div>
@@ -2507 +2508 @@
       <p id="rfc.section.7.4.1.p.3">If the server has a preferred choice of representation, it <em class="bcp14">SHOULD</em> include the specific URI for that representation in the <a href="#header.location" class="smpl">Location</a> field; user agents <em class="bcp14">MAY</em> use the Location field value for automatic redirection.
       </p>
-      <p id="rfc.section.7.4.1.p.4">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.13"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 300 responses.
+      <p id="rfc.section.7.4.1.p.4">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.12"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 300 responses.
       </p>
       <div id="rfc.iref.87"></div>
@@ -2515 +2516 @@
          request URI to one or more of the new references returned by the server, where possible.
       </p>
-      <p id="rfc.section.7.4.2.p.2">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.14"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 301 responses.
+      <p id="rfc.section.7.4.2.p.2">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.13"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 301 responses.
       </p>
       <p id="rfc.section.7.4.2.p.3">The new permanent URI <em class="bcp14">SHOULD</em> be given by the <a href="#header.location" class="smpl">Location</a> field in the response. A response payload can contain a short hypertext note with a hyperlink to the new URI(s).
@@ -2664 +2665 @@
          — that is left to the discretion of the server owner.
       </p>
-      <p id="rfc.section.7.5.9.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.15"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 410 responses.
+      <p id="rfc.section.7.5.9.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.14"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 410 responses.
       </p>
       <div id="rfc.iref.103"></div>
@@ -2856 +2857 @@
             <tbody>
                <tr>
+                  <td class="left">Age</td>
+                  <td class="left"><a href="p6-cache.html#header.age" title="Age">Section 7.1</a> of <a href="#Part6" id="rfc.xref.Part6.15"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a></td>
+               </tr>
+               <tr>
                   <td class="left">Date</td>
                   <td class="left"><a href="#header.date" id="rfc.xref.header.date.1" title="Date">Section&nbsp;8.2.1</a></td>
                </tr>
                <tr>
-                  <td class="left">Age</td>
-                  <td class="left"><a href="p6-cache.html#header.age" title="Age">Section 7.1</a> of <a href="#Part6" id="rfc.xref.Part6.16"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a></td>
-               </tr>
-               <tr>
                   <td class="left">Vary</td>
-                  <td class="left"><a href="p6-cache.html#header.vary" title="Vary">Section 7.5</a> of <a href="#Part6" id="rfc.xref.Part6.17"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a></td>
+                  <td class="left"><a href="#header.vary" id="rfc.xref.header.vary.2" title="Vary">Section&nbsp;8.2.2</a></td>
                </tr>
             </tbody>
@@ -2900 +2901 @@
          value.
       </p>
+      <div id="rfc.iref.v.1"></div>
+      <div id="rfc.iref.h.18"></div>
+      <h3 id="rfc.section.8.2.2"><a href="#rfc.section.8.2.2">8.2.2</a>&nbsp;<a id="header.vary" href="#header.vary">Vary</a></h3>
+      <p id="rfc.section.8.2.2.p.1">The "Vary" header field conveys the set of header fields that were used to select the representation.</p>
+      <p id="rfc.section.8.2.2.p.2">Caches use this information as part of determining whether a stored response can be used to satisfy a given request (<a href="p6-cache.html#caching.negotiated.responses" title="Using Negotiated Responses">Section 4.3</a> of <a href="#Part6" id="rfc.xref.Part6.16"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+      </p>
+      <p id="rfc.section.8.2.2.p.3">In uncacheable or stale responses, the Vary field value advises the user agent about the criteria that were used to select
+         the representation.
+      </p>
+      <div id="rfc.figure.u.42"></div><pre class="inline"><span id="rfc.iref.g.31"></span>  <a href="#header.vary" class="smpl">Vary</a> = "*" / 1#<a href="p1-messaging.html#header.fields" class="smpl">field-name</a>
+</pre><p id="rfc.section.8.2.2.p.5">The set of header fields named by the Vary field value is known as the selecting header fields.</p>
+      <p id="rfc.section.8.2.2.p.6">A server <em class="bcp14">SHOULD</em> include a Vary header field with any cacheable response that is subject to proactive negotiation. Doing so allows a cache
+         to properly interpret future requests on that resource and informs the user agent about the presence of negotiation on that
+         resource. A server <em class="bcp14">MAY</em> include a Vary header field with a non-cacheable response that is subject to proactive negotiation, since this might provide
+         the user agent with useful information about the dimensions over which the response varies at the time of the response.
+      </p>
+      <p id="rfc.section.8.2.2.p.7">A Vary field value of "*" signals that unspecified parameters not limited to the header fields (e.g., the network address
+         of the client), play a role in the selection of the response representation; therefore, a cache cannot determine whether this
+         response is appropriate. A proxy <em class="bcp14">MUST NOT</em> generate the "*" value.
+      </p>
+      <p id="rfc.section.8.2.2.p.8">The field-names given are not limited to the set of standard header fields defined by this specification. Field names are
+         case-insensitive.
+      </p>
       <h2 id="rfc.section.8.3"><a href="#rfc.section.8.3">8.3</a>&nbsp;<a id="response.auth" href="#response.auth">Authentication Challenges</a></h2>
       <p id="rfc.section.8.3.p.1">Authentication challenges indicate what mechanisms are available for the client to provide authentication credentials in future
@@ -2951 +2975 @@
       </div>
       <div id="rfc.iref.a.5"></div>
-      <div id="rfc.iref.h.18"></div>
+      <div id="rfc.iref.h.19"></div>
       <h3 id="rfc.section.8.4.1"><a href="#rfc.section.8.4.1">8.4.1</a>&nbsp;<a id="header.allow" href="#header.allow">Allow</a></h3>
       <p id="rfc.section.8.4.1.p.1">The "Allow" header field lists the set of methods advertised as supported by the target resource. The purpose of this field
          is strictly to inform the recipient of valid request methods associated with the resource.
       </p>
-      <div id="rfc.figure.u.42"></div><pre class="inline"><span id="rfc.iref.g.31"></span>  <a href="#header.allow" class="smpl">Allow</a> = #<a href="#method.overview" class="smpl">method</a>
+      <div id="rfc.figure.u.43"></div><pre class="inline"><span id="rfc.iref.g.32"></span>  <a href="#header.allow" class="smpl">Allow</a> = #<a href="#method.overview" class="smpl">method</a>
 </pre><p id="rfc.section.8.4.1.p.3">Example of use:</p>
-      <div id="rfc.figure.u.43"></div><pre class="text">  Allow: GET, HEAD, PUT
+      <div id="rfc.figure.u.44"></div><pre class="text">  Allow: GET, HEAD, PUT
 </pre><p id="rfc.section.8.4.1.p.5">The actual set of allowed methods is defined by the origin server at the time of each request.</p>
       <p id="rfc.section.8.4.1.p.6">A proxy <em class="bcp14">MUST NOT</em> modify the Allow header field — it does not need to understand all the methods specified in order to handle them according
@@ -2964 +2988 @@
       </p>
       <div id="rfc.iref.s.44"></div>
-      <div id="rfc.iref.h.19"></div>
+      <div id="rfc.iref.h.20"></div>
       <h3 id="rfc.section.8.4.2"><a href="#rfc.section.8.4.2">8.4.2</a>&nbsp;<a id="header.server" href="#header.server">Server</a></h3>
       <p id="rfc.section.8.4.2.p.1">The "Server" header field contains information about the software used by the origin server to handle the request.</p>
@@ -2970 +2994 @@
          identifying the application.
       </p>
-      <div id="rfc.figure.u.44"></div><pre class="inline"><span id="rfc.iref.g.32"></span>  <a href="#header.server" class="smpl">Server</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#imported.abnf" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#imported.abnf" class="smpl">comment</a> ) )
+      <div id="rfc.figure.u.45"></div><pre class="inline"><span id="rfc.iref.g.33"></span>  <a href="#header.server" class="smpl">Server</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#imported.abnf" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#imported.abnf" class="smpl">comment</a> ) )
 </pre><p id="rfc.section.8.4.2.p.4">Example:</p>
-      <div id="rfc.figure.u.45"></div><pre class="text">  Server: CERN/3.0 libwww/2.17
+      <div id="rfc.figure.u.46"></div><pre class="text">  Server: CERN/3.0 libwww/2.17
 </pre><p id="rfc.section.8.4.2.p.6">If the response is being forwarded through a proxy, the proxy application <em class="bcp14">MUST NOT</em> modify the <a href="#header.server" class="smpl">Server</a> header field. Instead, it <em class="bcp14">MUST</em> include a <a href="p1-messaging.html#header.via" class="smpl">Via</a> field (as described in <a href="p1-messaging.html#header.via" title="Via">Section 5.7</a> of <a href="#Part1" id="rfc.xref.Part1.26"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>).
       </p>
@@ -2986 +3010 @@
          a fixed-length subset of that defined by <a href="#RFC1123" id="rfc.xref.RFC1123.1"><cite title="Requirements for Internet Hosts - Application and Support">[RFC1123]</cite></a>:
       </p>
-      <div id="rfc.figure.u.46"></div><pre class="text">Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 1123
+      <div id="rfc.figure.u.47"></div><pre class="text">Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 1123
 </pre><p id="rfc.section.9.1.p.3">The other formats are described here only for compatibility with obsolete implementations.</p>
-      <div id="rfc.figure.u.47"></div><pre class="text">Sunday, 06-Nov-94 08:49:37 GMT ; obsolete RFC 850 format
+      <div id="rfc.figure.u.48"></div><pre class="text">Sunday, 06-Nov-94 08:49:37 GMT ; obsolete RFC 850 format
 Sun Nov  6 08:49:37 1994       ; ANSI C's asctime() format
 </pre><p id="rfc.section.9.1.p.5">HTTP/1.1 clients and servers that parse a date value <em class="bcp14">MUST</em> accept all three formats (for compatibility with HTTP/1.0), though they <em class="bcp14">MUST</em> only generate the RFC 1123 format for representing HTTP-date values in header fields.
@@ -2996 +3020 @@
          time zone, and <em class="bcp14">MUST</em> be assumed when reading the asctime format. HTTP-date is case sensitive and <em class="bcp14">MUST NOT</em> include additional whitespace beyond that specifically included as SP in the grammar.
       </p>
-      <div id="rfc.figure.u.48"></div><pre class="inline"><span id="rfc.iref.g.33"></span>  <a href="#http.date" class="smpl">HTTP-date</a>    = <a href="#preferred.date.format" class="smpl">rfc1123-date</a> / <a href="#obsolete.date.formats" class="smpl">obs-date</a>
+      <div id="rfc.figure.u.49"></div><pre class="inline"><span id="rfc.iref.g.34"></span>  <a href="#http.date" class="smpl">HTTP-date</a>    = <a href="#preferred.date.format" class="smpl">rfc1123-date</a> / <a href="#obsolete.date.formats" class="smpl">obs-date</a>
 </pre><div id="preferred.date.format">
          <p id="rfc.section.9.1.p.8">                    Preferred format:</p>
       </div>
-      <div id="rfc.figure.u.49"></div><pre class="inline"><span id="rfc.iref.g.34"></span><span id="rfc.iref.g.35"></span><span id="rfc.iref.g.36"></span><span id="rfc.iref.g.37"></span><span id="rfc.iref.g.38"></span><span id="rfc.iref.g.39"></span><span id="rfc.iref.g.40"></span><span id="rfc.iref.g.41"></span><span id="rfc.iref.g.42"></span><span id="rfc.iref.g.43"></span><span id="rfc.iref.g.44"></span><span id="rfc.iref.g.45"></span>  <a href="#preferred.date.format" class="smpl">rfc1123-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> "," <a href="#imported.abnf" class="smpl">SP</a> date1 <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
+      <div id="rfc.figure.u.50"></div><pre class="inline"><span id="rfc.iref.g.35"></span><span id="rfc.iref.g.36"></span><span id="rfc.iref.g.37"></span><span id="rfc.iref.g.38"></span><span id="rfc.iref.g.39"></span><span id="rfc.iref.g.40"></span><span id="rfc.iref.g.41"></span><span id="rfc.iref.g.42"></span><span id="rfc.iref.g.43"></span><span id="rfc.iref.g.44"></span><span id="rfc.iref.g.45"></span><span id="rfc.iref.g.46"></span>  <a href="#preferred.date.format" class="smpl">rfc1123-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> "," <a href="#imported.abnf" class="smpl">SP</a> date1 <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
   ; fixed length subset of the format defined in
   ; <a href="http://tools.ietf.org/html/rfc1123#section-5.2.14">Section 5.2.14</a> of <a href="#RFC1123" id="rfc.xref.RFC1123.2"><cite title="Requirements for Internet Hosts - Application and Support">[RFC1123]</cite></a>
@@ -3043 +3067 @@
          <p id="rfc.section.9.1.p.11">              Obsolete formats:</p>
       </div>
-      <div id="rfc.figure.u.50"></div><pre class="inline"><span id="rfc.iref.g.46"></span>  <a href="#obsolete.date.formats" class="smpl">obs-date</a>     = <a href="#obsolete.date.formats" class="smpl">rfc850-date</a> / <a href="#obsolete.date.formats" class="smpl">asctime-date</a> 
-</pre><div id="rfc.figure.u.51"></div><pre class="inline"><span id="rfc.iref.g.47"></span>  <a href="#obsolete.date.formats" class="smpl">rfc850-date</a>  = <a href="#obsolete.date.formats" class="smpl">day-name-l</a> "," <a href="#imported.abnf" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date2</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
+      <div id="rfc.figure.u.51"></div><pre class="inline"><span id="rfc.iref.g.47"></span>  <a href="#obsolete.date.formats" class="smpl">obs-date</a>     = <a href="#obsolete.date.formats" class="smpl">rfc850-date</a> / <a href="#obsolete.date.formats" class="smpl">asctime-date</a> 
+</pre><div id="rfc.figure.u.52"></div><pre class="inline"><span id="rfc.iref.g.48"></span>  <a href="#obsolete.date.formats" class="smpl">rfc850-date</a>  = <a href="#obsolete.date.formats" class="smpl">day-name-l</a> "," <a href="#imported.abnf" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date2</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
   <a href="#obsolete.date.formats" class="smpl">date2</a>        = <a href="#preferred.date.format" class="smpl">day</a> "-" <a href="#preferred.date.format" class="smpl">month</a> "-" 2<a href="#imported.abnf" class="smpl">DIGIT</a>
                  ; day-month-year (e.g., 02-Jun-82)
@@ -3055 +3079 @@
          / %x53.61.74.75.72.64.61.79 ; "Saturday", case-sensitive
          / %x53.75.6E.64.61.79 ; "Sunday", case-sensitive
-</pre><div id="rfc.figure.u.52"></div><pre class="inline"><span id="rfc.iref.g.48"></span>  <a href="#obsolete.date.formats" class="smpl">asctime-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date3</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
+</pre><div id="rfc.figure.u.53"></div><pre class="inline"><span id="rfc.iref.g.49"></span>  <a href="#obsolete.date.formats" class="smpl">asctime-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date3</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
   <a href="#obsolete.date.formats" class="smpl">date3</a>        = <a href="#preferred.date.format" class="smpl">month</a> <a href="#imported.abnf" class="smpl">SP</a> ( 2<a href="#imported.abnf" class="smpl">DIGIT</a> / ( <a href="#imported.abnf" class="smpl">SP</a> 1<a href="#imported.abnf" class="smpl">DIGIT</a> ))
                  ; month day (e.g., Jun  2)
@@ -3073 +3097 @@
          By convention, the products are listed in order of their significance for identifying the application.
       </p>
-      <div id="rfc.figure.u.53"></div><pre class="inline"><span id="rfc.iref.g.49"></span><span id="rfc.iref.g.50"></span>  <a href="#product.tokens" class="smpl">product</a>         = <a href="#imported.abnf" class="smpl">token</a> ["/" <a href="#product.tokens" class="smpl">product-version</a>]
+      <div id="rfc.figure.u.54"></div><pre class="inline"><span id="rfc.iref.g.50"></span><span id="rfc.iref.g.51"></span>  <a href="#product.tokens" class="smpl">product</a>         = <a href="#imported.abnf" class="smpl">token</a> ["/" <a href="#product.tokens" class="smpl">product-version</a>]
   <a href="#product.tokens" class="smpl">product-version</a> = <a href="#imported.abnf" class="smpl">token</a>
 </pre><p id="rfc.section.9.2.p.3">Examples:</p>
-      <div id="rfc.figure.u.54"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
+      <div id="rfc.figure.u.55"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
   Server: Apache/0.8.4
 </pre><p id="rfc.section.9.2.p.5">Product tokens <em class="bcp14">SHOULD</em> be short and to the point. They <em class="bcp14">MUST NOT</em> be used for advertising or other non-essential information. Although any token octet <em class="bcp14">MAY</em> appear in a product-version, this token <em class="bcp14">SHOULD</em> only be used for a version identifier (i.e., successive versions of the same product <em class="bcp14">SHOULD</em> only differ in the product-version portion of the product value).
@@ -3087 +3111 @@
          </p>
       </div>
-      <div id="rfc.figure.u.55"></div><pre class="inline"><span id="rfc.iref.g.51"></span>  <a href="#rule.charset" class="smpl">charset</a> = <a href="#imported.abnf" class="smpl">token</a>
+      <div id="rfc.figure.u.56"></div><pre class="inline"><span id="rfc.iref.g.52"></span>  <a href="#rule.charset" class="smpl">charset</a> = <a href="#imported.abnf" class="smpl">token</a>
 </pre><p id="rfc.section.9.3.p.4">Although HTTP allows an arbitrary token to be used as a charset value, any token that has a predefined value within the IANA
          Character Set registry <em class="bcp14">MUST</em> represent the character encoding defined by that registry. Applications <em class="bcp14">SHOULD</em> limit their use of character encodings to those defined within the IANA registry.
@@ -3101 +3125 @@
          directly, and only decoded by the recipient.
       </p>
-      <div id="rfc.figure.u.56"></div><pre class="inline"><span id="rfc.iref.g.52"></span>  <a href="#content.codings" class="smpl">content-coding</a>   = <a href="#imported.abnf" class="smpl">token</a>
+      <div id="rfc.figure.u.57"></div><pre class="inline"><span id="rfc.iref.g.53"></span>  <a href="#content.codings" class="smpl">content-coding</a>   = <a href="#imported.abnf" class="smpl">token</a>
 </pre><p id="rfc.section.9.4.p.3">All content-coding values are case-insensitive. HTTP/1.1 uses content-coding values in the <a href="#header.accept-encoding" class="smpl">Accept-Encoding</a> (<a href="#header.accept-encoding" id="rfc.xref.header.accept-encoding.3" title="Accept-Encoding">Section&nbsp;6.3.4</a>) and <a href="#header.content-encoding" class="smpl">Content-Encoding</a> (<a href="#header.content-encoding" id="rfc.xref.header.content-encoding.2" title="Content-Encoding">Section&nbsp;3.2.2</a>) header fields. Although the value describes the content-coding, what is more important is that it indicates what decoding
          mechanism will be required to remove the encoding.
@@ -3117 +3141 @@
          </li>
       </ul>
-      <p id="rfc.section.9.4.p.6">gzip<span id="rfc.iref.g.53"></span><span id="rfc.iref.c.11"></span>  
+      <p id="rfc.section.9.4.p.6">gzip<span id="rfc.iref.g.54"></span><span id="rfc.iref.c.11"></span>  
       </p>
       <ul class="empty">
@@ -3126 +3150 @@
       <p id="rfc.section.9.5.p.1">HTTP uses Internet Media Types <a href="#RFC2046" id="rfc.xref.RFC2046.2"><cite title="Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types">[RFC2046]</cite></a> in the <a href="#header.content-type" class="smpl">Content-Type</a> (<a href="#header.content-type" id="rfc.xref.header.content-type.3" title="Content-Type">Section&nbsp;3.2.1</a>) and <a href="#header.accept" class="smpl">Accept</a> (<a href="#header.accept" id="rfc.xref.header.accept.3" title="Accept">Section&nbsp;6.3.2</a>) header fields in order to provide open and extensible data typing and type negotiation.
       </p>
-      <div id="rfc.figure.u.57"></div><pre class="inline"><span id="rfc.iref.g.54"></span><span id="rfc.iref.g.55"></span><span id="rfc.iref.g.56"></span>  <a href="#media.types" class="smpl">media-type</a> = <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> *( <a href="#imported.abnf" class="smpl">OWS</a> ";" <a href="#imported.abnf" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
+      <div id="rfc.figure.u.58"></div><pre class="inline"><span id="rfc.iref.g.55"></span><span id="rfc.iref.g.56"></span><span id="rfc.iref.g.57"></span>  <a href="#media.types" class="smpl">media-type</a> = <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> *( <a href="#imported.abnf" class="smpl">OWS</a> ";" <a href="#imported.abnf" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
   <a href="#media.types" class="smpl">type</a>       = <a href="#imported.abnf" class="smpl">token</a>
   <a href="#media.types" class="smpl">subtype</a>    = <a href="#imported.abnf" class="smpl">token</a>
@@ -3133 +3157 @@
          </p>
       </div>
-      <div id="rfc.figure.u.58"></div><pre class="inline"><span id="rfc.iref.g.57"></span><span id="rfc.iref.g.58"></span><span id="rfc.iref.g.59"></span>  <a href="#rule.parameter" class="smpl">parameter</a>      = <a href="#rule.parameter" class="smpl">attribute</a> "=" <a href="#rule.parameter" class="smpl">value</a>
+      <div id="rfc.figure.u.59"></div><pre class="inline"><span id="rfc.iref.g.58"></span><span id="rfc.iref.g.59"></span><span id="rfc.iref.g.60"></span>  <a href="#rule.parameter" class="smpl">parameter</a>      = <a href="#rule.parameter" class="smpl">attribute</a> "=" <a href="#rule.parameter" class="smpl">value</a>
   <a href="#rule.parameter" class="smpl">attribute</a>      = <a href="#imported.abnf" class="smpl">token</a>
   <a href="#rule.parameter" class="smpl">value</a>          = <a href="#imported.abnf" class="smpl">word</a>
@@ -3183 +3207 @@
          of subtags:
       </p>
-      <div id="rfc.figure.u.59"></div><pre class="inline"><span id="rfc.iref.g.60"></span>  <a href="#language.tags" class="smpl">language-tag</a> = &lt;Language-Tag, defined in <a href="#RFC5646" id="rfc.xref.RFC5646.2"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a>, <a href="http://tools.ietf.org/html/rfc5646#section-2.1">Section 2.1</a>&gt;
+      <div id="rfc.figure.u.60"></div><pre class="inline"><span id="rfc.iref.g.61"></span>  <a href="#language.tags" class="smpl">language-tag</a> = &lt;Language-Tag, defined in <a href="#RFC5646" id="rfc.xref.RFC5646.2"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a>, <a href="http://tools.ietf.org/html/rfc5646#section-2.1">Section 2.1</a>&gt;
 </pre><p id="rfc.section.9.6.p.4">White space is not allowed within the tag and all tags are case-insensitive. The name space of language subtags is administered
          by the IANA (see &lt;<a href="http://www.iana.org/assignments/language-subtag-registry">http://www.iana.org/assignments/language-subtag-registry</a>&gt;).
       </p>
-      <div id="rfc.figure.u.60"></div> 
+      <div id="rfc.figure.u.61"></div> 
       <p>Example tags include:</p>  <pre class="text">  en, en-US, es-419, az-Arab, x-pig-latin, man-Nkoo-GN
 </pre> <p id="rfc.section.9.6.p.6">See <a href="#RFC5646" id="rfc.xref.RFC5646.3"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a> for further information.
@@ -3319 +3343 @@
          a zero-length response body. They can require the presence of one or more particular HTTP response header field(s).
       </p>
-      <p id="rfc.section.10.2.2.p.5">Likewise, their definitions can specify that caches are allowed to use heuristics to determine their freshness (see <a href="#Part6" id="rfc.xref.Part6.18"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>; by default, it is not allowed), and can define how to determine the resource which they carry a representation for (see <a href="#identifying.response.associated.with.representation" title="Identifying the Resource Associated with a Representation">Section&nbsp;3.1</a>; by default, it is anonymous).
+      <p id="rfc.section.10.2.2.p.5">Likewise, their definitions can specify that caches are allowed to use heuristics to determine their freshness (see <a href="#Part6" id="rfc.xref.Part6.17"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>; by default, it is not allowed), and can define how to determine the resource which they carry a representation for (see <a href="#identifying.response.associated.with.representation" title="Identifying the Resource Associated with a Representation">Section&nbsp;3.1</a>; by default, it is anonymous).
       </p>
       <h3 id="rfc.section.10.2.3"><a href="#rfc.section.10.2.3">10.2.3</a>&nbsp;<a id="status.code.registration" href="#status.code.registration">Registrations</a></h3>
@@ -3573 +3597 @@
          these:
       </p>
-      <div id="rfc.figure.u.61"></div><pre class="text">  Example-URI-Field: "http://example.com/a.html,foo",
+      <div id="rfc.figure.u.62"></div><pre class="text">  Example-URI-Field: "http://example.com/a.html,foo",
                      "http://without-a-comma.example.com/"
   Example-Date-Field: "Sat, 04 May 1996", "Wed, 14 Sep 2005"
@@ -3609 +3633 @@
          </li>
          <li>
-            <p>How the header field might interact with caching (see <a href="#Part6" id="rfc.xref.Part6.19"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
+            <p>How the header field might interact with caching (see <a href="#Part6" id="rfc.xref.Part6.18"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
             </p>
          </li>
@@ -3765 +3789 @@
                   <td class="left">standard</td>
                   <td class="left"> <a href="#header.user-agent" id="rfc.xref.header.user-agent.3" title="User-Agent">Section&nbsp;6.5.3</a> 
+                  </td>
+               </tr>
+               <tr>
+                  <td class="left">Vary</td>
+                  <td class="left">http</td>
+                  <td class="left">standard</td>
+                  <td class="left"> <a href="#header.vary" id="rfc.xref.header.vary.3" title="Vary">Section&nbsp;8.2.2</a> 
                   </td>
                </tr>
@@ -3895 +3926 @@
       <p id="rfc.section.11.5.p.2">An approach that limits the loss of privacy would be for a user agent to omit the sending of Accept-Language header fields
          by default, and to ask the user whether or not to start sending Accept-Language header fields to a server if it detects, by
-         looking for any <a href="p6-cache.html#header.vary" class="smpl">Vary</a> header fields generated by the server, that such sending could improve the quality of service.
+         looking for any <a href="#header.vary" class="smpl">Vary</a> header fields generated by the server, that such sending could improve the quality of service.
       </p>
       <p id="rfc.section.11.5.p.3">Elaborate user-customized accept header fields sent in every request, in particular if these include quality values, can be
@@ -4126 +4157 @@
       </p>
       <div id="rfc.iref.m.10"></div>
-      <div id="rfc.iref.h.20"></div>
+      <div id="rfc.iref.h.21"></div>
       <h2 id="rfc.section.A.1"><a href="#rfc.section.A.1">A.1</a>&nbsp;<a id="mime-version" href="#mime-version">MIME-Version</a></h2>
       <p id="rfc.section.A.1.p.1">HTTP is not a MIME-compliant protocol. However, HTTP/1.1 messages <em class="bcp14">MAY</em> include a single MIME-Version header field to indicate what version of the MIME protocol was used to construct the message.
@@ -4133 +4164 @@
          MIME environments.
       </p>
-      <div id="rfc.figure.u.62"></div><pre class="inline"><span id="rfc.iref.g.61"></span>  <a href="#mime-version" class="smpl">MIME-Version</a> = 1*<a href="#imported.abnf" class="smpl">DIGIT</a> "." 1*<a href="#imported.abnf" class="smpl">DIGIT</a>
+      <div id="rfc.figure.u.63"></div><pre class="inline"><span id="rfc.iref.g.62"></span>  <a href="#mime-version" class="smpl">MIME-Version</a> = 1*<a href="#imported.abnf" class="smpl">DIGIT</a> "." 1*<a href="#imported.abnf" class="smpl">DIGIT</a>
 </pre><p id="rfc.section.A.1.p.3">MIME version "1.0" is the default for use in HTTP/1.1. However, HTTP/1.1 message parsing and semantics are defined by this
          document and not the MIME specification.
@@ -4158 +4189 @@
       </p>
       <div id="rfc.iref.c.12"></div>
-      <div id="rfc.iref.h.21"></div>
+      <div id="rfc.iref.h.22"></div>
       <h2 id="rfc.section.A.5"><a href="#rfc.section.A.5">A.5</a>&nbsp;<a id="no.content-transfer-encoding" href="#no.content-transfer-encoding">No Content-Transfer-Encoding</a></h2>
       <p id="rfc.section.A.5.p.1">HTTP does not use the Content-Transfer-Encoding field of MIME. Proxies and gateways from MIME-compliant protocols to HTTP <em class="bcp14">MUST</em> remove any Content-Transfer-Encoding prior to delivering the response message to an HTTP client.
@@ -4248 +4279 @@
       <p id="rfc.section.D.p.2">The rules below are defined in <a href="#Part1" id="rfc.xref.Part1.45"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>:
       </p>
-      <div id="rfc.figure.u.63"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.46"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
+      <div id="rfc.figure.u.64"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.46"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
   <a href="#imported.abnf" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.47"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
   <a href="#imported.abnf" class="smpl">RWS</a>           = &lt;RWS, defined in <a href="#Part1" id="rfc.xref.Part1.48"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
@@ -4260 +4291 @@
   <a href="#imported.abnf" class="smpl">URI-reference</a> = &lt;URI-reference, defined in <a href="#Part1" id="rfc.xref.Part1.55"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.7</a>&gt;
 </pre><h1 id="rfc.section.E"><a href="#rfc.section.E">E.</a>&nbsp;<a id="collected.abnf" href="#collected.abnf">Collected ABNF</a></h1>
-      <div id="rfc.figure.u.64"></div> <pre class="inline"><a href="#header.accept" class="smpl">Accept</a> = [ ( "," / ( media-range [ accept-params ] ) ) *( OWS "," [
+      <div id="rfc.figure.u.65"></div> <pre class="inline"><a href="#header.accept" class="smpl">Accept</a> = [ ( "," / ( media-range [ accept-params ] ) ) *( OWS "," [
  OWS ( media-range [ accept-params ] ) ] ) ]
 <a href="#header.accept-charset" class="smpl">Accept-Charset</a> = *( "," OWS ) ( ( charset / "*" ) [ weight ] ) *( OWS
@@ -4305 +4336 @@
 <a href="#header.user-agent" class="smpl">User-Agent</a> = product *( RWS ( product / comment ) )
 
+<a href="#header.vary" class="smpl">Vary</a> = "*" / ( *( "," OWS ) field-name *( OWS "," [ OWS field-name ]
+ ) )
+
 <a href="#imported.abnf" class="smpl">absolute-URI</a> = &lt;absolute-URI, defined in [Part1], Section 2.7&gt;
+
 <a href="#header.accept" class="smpl">accept-ext</a> = OWS ";" OWS token [ "=" word ]
 <a href="#header.accept" class="smpl">accept-params</a> = weight *accept-ext
@@ -4312 +4347 @@
 
 <a href="#rule.charset" class="smpl">charset</a> = token
+
 <a href="#header.accept-encoding" class="smpl">codings</a> = content-coding / "identity" / "*"
 <a href="#imported.abnf" class="smpl">comment</a> = &lt;comment, defined in [Part1], Section 3.2.4&gt;
@@ -4317 +4353 @@
 
 <a href="#obsolete.date.formats" class="smpl">date1</a> = day SP month SP year
+
 <a href="#obsolete.date.formats" class="smpl">date2</a> = day "-" month "-" 2DIGIT
 <a href="#obsolete.date.formats" class="smpl">date3</a> = month SP ( 2DIGIT / ( SP DIGIT ) )
@@ -4337 +4374 @@
 
 <a href="#header.expect" class="smpl">expect-name</a> = token
+
 <a href="#header.expect" class="smpl">expect-param</a> = expect-name [ BWS "=" BWS expect-value ]
 <a href="#header.expect" class="smpl">expect-value</a> = token / quoted-string
@@ -4345 +4383 @@
 
 <a href="#header.accept-language" class="smpl">language-range</a> = &lt;language-range, defined in [RFC4647], Section 2.1&gt;
+
 <a href="#language.tags" class="smpl">language-tag</a> = &lt;Language-Tag, defined in [RFC5646], Section 2.1&gt;
 
 <a href="#header.from" class="smpl">mailbox</a> = &lt;mailbox, defined in [RFC5322], Section 3.4&gt;
+
 <a href="#header.accept" class="smpl">media-range</a> = ( "*/*" / ( type "/*" ) / ( type "/" subtype ) ) *( OWS
  ";" OWS parameter )
@@ -4369 +4409 @@
 
 <a href="#rule.parameter" class="smpl">parameter</a> = attribute "=" value
+
 <a href="#imported.abnf" class="smpl">partial-URI</a> = &lt;partial-URI, defined in [Part1], Section 2.7&gt;
 <a href="#product.tokens" class="smpl">product</a> = token [ "/" product-version ]
@@ -4374 +4415 @@
 
 <a href="#imported.abnf" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 3.2.4&gt;
+
 <a href="#quality.values" class="smpl">qvalue</a> = ( "0" [ "." *3DIGIT ] ) / ( "1" [ "." *3"0" ] )
 
 <a href="#preferred.date.format" class="smpl">rfc1123-date</a> = day-name "," SP date1 SP time-of-day SP GMT
+
 <a href="#obsolete.date.formats" class="smpl">rfc850-date</a> = day-name-l "," SP date2 SP time-of-day SP GMT
 
 <a href="#preferred.date.format" class="smpl">second</a> = 2DIGIT
+
 <a href="#media.types" class="smpl">subtype</a> = token
 
 <a href="#preferred.date.format" class="smpl">time-of-day</a> = hour ":" minute ":" second
+
 <a href="#imported.abnf" class="smpl">token</a> = &lt;token, defined in [Part1], Section 3.2.4&gt;
 <a href="#media.types" class="smpl">type</a> = token
@@ -4389 +4434 @@
 
 <a href="#quality.values" class="smpl">weight</a> = OWS ";" OWS "q=" qvalue
+
 <a href="#imported.abnf" class="smpl">word</a> = &lt;word, defined in [Part1], Section 3.2.4&gt;
 
 <a href="#preferred.date.format" class="smpl">year</a> = 4DIGIT
-</pre> <h1 id="rfc.section.F"><a href="#rfc.section.F">F.</a>&nbsp;<a id="change.log" href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
+</pre> <div id="rfc.figure.u.66"></div>
+      <p>ABNF diagnostics:</p><pre class="inline">; field-name UNDEFINED
+</pre><h1 id="rfc.section.F"><a href="#rfc.section.F">F.</a>&nbsp;<a id="change.log" href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
       <h2 id="rfc.section.F.1"><a href="#rfc.section.F.1">F.1</a>&nbsp;Since RFC 2616
       </h2>
@@ -4959 +5007 @@
       <p id="rfc.section.F.41.p.1">None yet.</p>
       <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
-      <p class="noprint"><a href="#rfc.index.1">1</a> <a href="#rfc.index.2">2</a> <a href="#rfc.index.3">3</a> <a href="#rfc.index.4">4</a> <a href="#rfc.index.5">5</a> <a href="#rfc.index.A">A</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.D">D</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.I">I</a> <a href="#rfc.index.L">L</a> <a href="#rfc.index.M">M</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.T">T</a> <a href="#rfc.index.U">U</a> 
+      <p class="noprint"><a href="#rfc.index.1">1</a> <a href="#rfc.index.2">2</a> <a href="#rfc.index.3">3</a> <a href="#rfc.index.4">4</a> <a href="#rfc.index.5">5</a> <a href="#rfc.index.A">A</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.D">D</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.I">I</a> <a href="#rfc.index.L">L</a> <a href="#rfc.index.M">M</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.T">T</a> <a href="#rfc.index.U">U</a> <a href="#rfc.index.V">V</a> 
       </p>
       <div class="print2col">
@@ -5076 +5124 @@
                         <li><tt>Accept-Language</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.22"><b>6.3.5</b></a></li>
                         <li><tt>accept-params</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.17"><b>6.3.2</b></a></li>
-                        <li><tt>Allow</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.31"><b>8.4.1</b></a></li>
-                        <li><tt>asctime-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.48"><b>9.1</b></a></li>
-                        <li><tt>attribute</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.58"><b>9.5</b></a></li>
-                        <li><tt>charset</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.51"><b>9.3</b></a></li>
+                        <li><tt>Allow</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.32"><b>8.4.1</b></a></li>
+                        <li><tt>asctime-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.49"><b>9.1</b></a></li>
+                        <li><tt>attribute</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.59"><b>9.5</b></a></li>
+                        <li><tt>charset</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.52"><b>9.3</b></a></li>
                         <li><tt>codings</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.21"><b>6.3.4</b></a></li>
-                        <li><tt>content-coding</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.52"><b>9.4</b></a></li>
+                        <li><tt>content-coding</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.53"><b>9.4</b></a></li>
                         <li><tt>Content-Encoding</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.2"><b>3.2.2</b></a></li>
                         <li><tt>Content-Language</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.3"><b>3.2.3</b></a></li>
@@ -5087 +5135 @@
                         <li><tt>Content-Type</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.1"><b>3.2.1</b></a></li>
                         <li><tt>Date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.30"><b>8.2.1</b></a></li>
-                        <li><tt>date1</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.35"><b>9.1</b></a></li>
-                        <li><tt>day</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.42"><b>9.1</b></a></li>
-                        <li><tt>day-name</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.40"><b>9.1</b></a></li>
-                        <li><tt>day-name-l</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.41"><b>9.1</b></a></li>
+                        <li><tt>date1</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.36"><b>9.1</b></a></li>
+                        <li><tt>day</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.43"><b>9.1</b></a></li>
+                        <li><tt>day-name</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.41"><b>9.1</b></a></li>
+                        <li><tt>day-name-l</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.42"><b>9.1</b></a></li>
                         <li><tt>delta-seconds</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.29"><b>8.1.2</b></a></li>
                         <li><tt>Expect</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.8"><b>6.1.2</b></a></li>
@@ -5098 +5146 @@
                         <li><tt>expectation</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.9"><b>6.1.2</b></a></li>
                         <li><tt>From</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.24"><b>6.5.1</b></a></li>
-                        <li><tt>GMT</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.45"><b>9.1</b></a></li>
-                        <li><tt>hour</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.37"><b>9.1</b></a></li>
-                        <li><tt>HTTP-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.33"><b>9.1</b></a></li>
+                        <li><tt>GMT</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.46"><b>9.1</b></a></li>
+                        <li><tt>hour</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.38"><b>9.1</b></a></li>
+                        <li><tt>HTTP-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.34"><b>9.1</b></a></li>
                         <li><tt>language-range</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.23"><b>6.3.5</b></a></li>
-                        <li><tt>language-tag</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.60"><b>9.6</b></a></li>
+                        <li><tt>language-tag</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.61"><b>9.6</b></a></li>
                         <li><tt>Location</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.27"><b>8.1.1</b></a></li>
                         <li><tt>Max-Forwards</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.7"><b>6.1.1</b></a></li>
                         <li><tt>media-range</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.16"><b>6.3.2</b></a></li>
-                        <li><tt>media-type</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.54"><b>9.5</b></a></li>
+                        <li><tt>media-type</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.55"><b>9.5</b></a></li>
                         <li><tt>method</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.5"><b>5.1</b></a></li>
-                        <li><tt>MIME-Version</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.61"><b>A.1</b></a></li>
-                        <li><tt>minute</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.38"><b>9.1</b></a></li>
-                        <li><tt>month</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.43"><b>9.1</b></a></li>
-                        <li><tt>obs-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.46"><b>9.1</b></a></li>
-                        <li><tt>parameter</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.57"><b>9.5</b></a></li>
-                        <li><tt>product</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.49"><b>9.2</b></a></li>
-                        <li><tt>product-version</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.50"><b>9.2</b></a></li>
+                        <li><tt>MIME-Version</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.62"><b>A.1</b></a></li>
+                        <li><tt>minute</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.39"><b>9.1</b></a></li>
+                        <li><tt>month</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.44"><b>9.1</b></a></li>
+                        <li><tt>obs-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.47"><b>9.1</b></a></li>
+                        <li><tt>parameter</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.58"><b>9.5</b></a></li>
+                        <li><tt>product</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.50"><b>9.2</b></a></li>
+                        <li><tt>product-version</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.51"><b>9.2</b></a></li>
                         <li><tt>qvalue</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.14"><b>6.3.1</b></a></li>
                         <li><tt>Referer</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.25"><b>6.5.2</b></a></li>
                         <li><tt>Retry-After</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.28"><b>8.1.2</b></a></li>
-                        <li><tt>rfc1123-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.34"><b>9.1</b></a></li>
-                        <li><tt>rfc850-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.47"><b>9.1</b></a></li>
-                        <li><tt>second</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.39"><b>9.1</b></a></li>
-                        <li><tt>Server</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.32"><b>8.4.2</b></a></li>
-                        <li><tt>subtype</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.56"><b>9.5</b></a></li>
-                        <li><tt>time-of-day</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.36"><b>9.1</b></a></li>
-                        <li><tt>type</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.55"><b>9.5</b></a></li>
+                        <li><tt>rfc1123-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.35"><b>9.1</b></a></li>
+                        <li><tt>rfc850-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.48"><b>9.1</b></a></li>
+                        <li><tt>second</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.40"><b>9.1</b></a></li>
+                        <li><tt>Server</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.33"><b>8.4.2</b></a></li>
+                        <li><tt>subtype</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.57"><b>9.5</b></a></li>
+                        <li><tt>time-of-day</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.37"><b>9.1</b></a></li>
+                        <li><tt>type</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.56"><b>9.5</b></a></li>
                         <li><tt>User-Agent</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.26"><b>6.5.3</b></a></li>
-                        <li><tt>value</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.59"><b>9.5</b></a></li>
+                        <li><tt>value</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.60"><b>9.5</b></a></li>
+                        <li><tt>Vary</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.31"><b>8.2.2</b></a></li>
                         <li><tt>weight</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.13"><b>6.3.1</b></a></li>
-                        <li><tt>year</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.44"><b>9.1</b></a></li>
+                        <li><tt>year</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.45"><b>9.1</b></a></li>
                      </ul>
                   </li>
-                  <li>gzip (Coding Format)&nbsp;&nbsp;<a href="#rfc.iref.g.53">9.4</a></li>
+                  <li>gzip (Coding Format)&nbsp;&nbsp;<a href="#rfc.iref.g.54">9.4</a></li>
                </ul>
             </li>
@@ -5142 +5191 @@
                         <li>Accept-Encoding&nbsp;&nbsp;<a href="#rfc.xref.header.accept-encoding.1">3.5.1</a>, <a href="#rfc.xref.header.accept-encoding.2">6.3</a>, <a href="#rfc.iref.h.10"><b>6.3.4</b></a>, <a href="#rfc.xref.header.accept-encoding.3">9.4</a>, <a href="#rfc.xref.header.accept-encoding.4">10.3.2</a>, <a href="#rfc.xref.header.accept-encoding.5">10.4.2</a></li>
                         <li>Accept-Language&nbsp;&nbsp;<a href="#rfc.xref.header.accept-language.1">3.5.1</a>, <a href="#rfc.xref.header.accept-language.2">6.3</a>, <a href="#rfc.iref.h.11"><b>6.3.5</b></a>, <a href="#rfc.xref.header.accept-language.3">10.3.2</a></li>
-                        <li>Allow&nbsp;&nbsp;<a href="#rfc.xref.header.allow.1">5.1</a>, <a href="#rfc.xref.header.allow.2">8.4</a>, <a href="#rfc.iref.h.18"><b>8.4.1</b></a>, <a href="#rfc.xref.header.allow.3">10.3.2</a>, <a href="#rfc.xref.header.allow.4">C</a></li>
+                        <li>Allow&nbsp;&nbsp;<a href="#rfc.xref.header.allow.1">5.1</a>, <a href="#rfc.xref.header.allow.2">8.4</a>, <a href="#rfc.iref.h.19"><b>8.4.1</b></a>, <a href="#rfc.xref.header.allow.3">10.3.2</a>, <a href="#rfc.xref.header.allow.4">C</a></li>
                         <li>Content-Encoding&nbsp;&nbsp;<a href="#rfc.xref.header.content-encoding.1">3.2</a>, <a href="#rfc.iref.h.2"><b>3.2.2</b></a>, <a href="#rfc.xref.header.content-encoding.2">9.4</a>, <a href="#rfc.xref.header.content-encoding.3">10.3.2</a></li>
                         <li>Content-Language&nbsp;&nbsp;<a href="#rfc.xref.header.content-language.1">3.2</a>, <a href="#rfc.iref.h.3"><b>3.2.3</b></a>, <a href="#rfc.xref.header.content-language.2">10.3.2</a></li>
                         <li>Content-Location&nbsp;&nbsp;<a href="#rfc.xref.header.content-location.1">3.2</a>, <a href="#rfc.iref.h.4"><b>3.2.4</b></a>, <a href="#rfc.xref.header.content-location.2">5.3.3</a>, <a href="#rfc.xref.header.content-location.3">8.1.1</a>, <a href="#rfc.xref.header.content-location.4">10.3.2</a>, <a href="#rfc.xref.header.content-location.5">C</a></li>
-                        <li>Content-Transfer-Encoding&nbsp;&nbsp;<a href="#rfc.iref.h.21">A.5</a>, <a href="#rfc.xref.no.content-transfer-encoding.1">C</a></li>
+                        <li>Content-Transfer-Encoding&nbsp;&nbsp;<a href="#rfc.iref.h.22">A.5</a>, <a href="#rfc.xref.no.content-transfer-encoding.1">C</a></li>
                         <li>Content-Type&nbsp;&nbsp;<a href="#rfc.xref.header.content-type.1">3.2</a>, <a href="#rfc.iref.h.1"><b>3.2.1</b></a>, <a href="#rfc.xref.header.content-type.2">7</a>, <a href="#rfc.xref.header.content-type.3">9.5</a>, <a href="#rfc.xref.header.content-type.4">10.3.1</a>, <a href="#rfc.xref.header.content-type.5">10.3.2</a></li>
                         <li>Date&nbsp;&nbsp;<a href="#rfc.xref.header.date.1">8.2</a>, <a href="#rfc.iref.h.17"><b>8.2.1</b></a>, <a href="#rfc.xref.header.date.2">10.3.2</a></li>
@@ -5153 +5202 @@
                         <li>Location&nbsp;&nbsp;<a href="#rfc.xref.header.location.1">5.3.3</a>, <a href="#rfc.xref.header.location.2">7.4</a>, <a href="#rfc.xref.header.location.3">8.1</a>, <a href="#rfc.iref.h.15"><b>8.1.1</b></a>, <a href="#rfc.xref.header.location.4">10.3.2</a>, <a href="#rfc.xref.header.location.5">C</a></li>
                         <li>Max-Forwards&nbsp;&nbsp;<a href="#rfc.xref.header.max-forwards.1">5.3.7</a>, <a href="#rfc.xref.header.max-forwards.2">5.3.8</a>, <a href="#rfc.xref.header.max-forwards.3">6.1</a>, <a href="#rfc.iref.h.6"><b>6.1.1</b></a>, <a href="#rfc.xref.header.max-forwards.4">10.3.2</a>, <a href="#rfc.xref.header.max-forwards.5">C</a></li>
-                        <li>MIME-Version&nbsp;&nbsp;<a href="#rfc.xref.mime-version.1">10.3.2</a>, <a href="#rfc.iref.h.20"><b>A.1</b></a></li>
+                        <li>MIME-Version&nbsp;&nbsp;<a href="#rfc.xref.mime-version.1">10.3.2</a>, <a href="#rfc.iref.h.21"><b>A.1</b></a></li>
                         <li>Referer&nbsp;&nbsp;<a href="#rfc.xref.header.referer.1">6.5</a>, <a href="#rfc.iref.h.13"><b>6.5.2</b></a>, <a href="#rfc.xref.header.referer.2">10.3.2</a>, <a href="#rfc.xref.header.referer.3">C</a></li>
                         <li>Retry-After&nbsp;&nbsp;<a href="#rfc.xref.header.retry-after.1">7.6.4</a>, <a href="#rfc.xref.header.retry-after.2">8.1</a>, <a href="#rfc.iref.h.16"><b>8.1.2</b></a>, <a href="#rfc.xref.header.retry-after.3">10.3.2</a></li>
-                        <li>Server&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">8.4</a>, <a href="#rfc.iref.h.19"><b>8.4.2</b></a>, <a href="#rfc.xref.header.server.2">10.3.2</a>, <a href="#rfc.xref.header.server.3">11.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
+                        <li>Server&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">8.4</a>, <a href="#rfc.iref.h.20"><b>8.4.2</b></a>, <a href="#rfc.xref.header.server.2">10.3.2</a>, <a href="#rfc.xref.header.server.3">11.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
                         <li>User-Agent&nbsp;&nbsp;<a href="#rfc.xref.header.user-agent.1">3.5.1</a>, <a href="#rfc.xref.header.user-agent.2">6.5</a>, <a href="#rfc.iref.h.14"><b>6.5.3</b></a>, <a href="#rfc.xref.header.user-agent.3">10.3.2</a>, <a href="#rfc.xref.header.user-agent.4">11.1</a></li>
+                        <li>Vary&nbsp;&nbsp;<a href="#rfc.xref.header.vary.1">3.5.1</a>, <a href="#rfc.xref.header.vary.2">8.2</a>, <a href="#rfc.iref.h.18"><b>8.2.2</b></a>, <a href="#rfc.xref.header.vary.3">10.3.2</a></li>
                      </ul>
                   </li>
@@ -5243 +5293 @@
                      </ul>
                   </li>
-                  <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">3.2</a>, <a href="#rfc.xref.Part6.2">3.5.1</a>, <a href="#rfc.xref.Part6.3">5.2.3</a>, <a href="#rfc.xref.Part6.4">5.3.1</a>, <a href="#rfc.xref.Part6.5">5.3.2</a>, <a href="#rfc.xref.Part6.6">5.3.3</a>, <a href="#rfc.xref.Part6.7">5.3.4</a>, <a href="#rfc.xref.Part6.8">5.3.5</a>, <a href="#rfc.xref.Part6.9">7.3.1</a>, <a href="#rfc.xref.Part6.10">7.3.4</a>, <a href="#rfc.xref.Part6.11">7.3.4</a>, <a href="#rfc.xref.Part6.12">7.3.4</a>, <a href="#rfc.xref.Part6.13">7.4.1</a>, <a href="#rfc.xref.Part6.14">7.4.2</a>, <a href="#rfc.xref.Part6.15">7.5.9</a>, <a href="#rfc.xref.Part6.16">8.2</a>, <a href="#rfc.xref.Part6.17">8.2</a>, <a href="#rfc.xref.Part6.18">10.2.2</a>, <a href="#rfc.xref.Part6.19">10.3.1</a>, <a href="#Part6"><b>13.1</b></a><ul>
-                        <li><em>Section 4.1.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.6">5.3.3</a></li>
-                        <li><em>Section 4.1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.9">7.3.1</a>, <a href="#rfc.xref.Part6.12">7.3.4</a>, <a href="#rfc.xref.Part6.13">7.4.1</a>, <a href="#rfc.xref.Part6.14">7.4.2</a>, <a href="#rfc.xref.Part6.15">7.5.9</a></li>
-                        <li><em>Section 5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.5">5.3.2</a></li>
-                        <li><em>Section 6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.7">5.3.4</a>, <a href="#rfc.xref.Part6.8">5.3.5</a></li>
-                        <li><em>Section 7.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.16">8.2</a></li>
-                        <li><em>Section 7.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.10">7.3.4</a></li>
+                  <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">3.2</a>, <a href="#rfc.xref.Part6.2">5.2.3</a>, <a href="#rfc.xref.Part6.3">5.3.1</a>, <a href="#rfc.xref.Part6.4">5.3.2</a>, <a href="#rfc.xref.Part6.5">5.3.3</a>, <a href="#rfc.xref.Part6.6">5.3.4</a>, <a href="#rfc.xref.Part6.7">5.3.5</a>, <a href="#rfc.xref.Part6.8">7.3.1</a>, <a href="#rfc.xref.Part6.9">7.3.4</a>, <a href="#rfc.xref.Part6.10">7.3.4</a>, <a href="#rfc.xref.Part6.11">7.3.4</a>, <a href="#rfc.xref.Part6.12">7.4.1</a>, <a href="#rfc.xref.Part6.13">7.4.2</a>, <a href="#rfc.xref.Part6.14">7.5.9</a>, <a href="#rfc.xref.Part6.15">8.2</a>, <a href="#rfc.xref.Part6.16">8.2.2</a>, <a href="#rfc.xref.Part6.17">10.2.2</a>, <a href="#rfc.xref.Part6.18">10.3.1</a>, <a href="#Part6"><b>13.1</b></a><ul>
+                        <li><em>Section 4.1.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.5">5.3.3</a></li>
+                        <li><em>Section 4.1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.8">7.3.1</a>, <a href="#rfc.xref.Part6.11">7.3.4</a>, <a href="#rfc.xref.Part6.12">7.4.1</a>, <a href="#rfc.xref.Part6.13">7.4.2</a>, <a href="#rfc.xref.Part6.14">7.5.9</a></li>
+                        <li><em>Section 4.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.16">8.2.2</a></li>
+                        <li><em>Section 5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.4">5.3.2</a></li>
+                        <li><em>Section 6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.6">5.3.4</a>, <a href="#rfc.xref.Part6.7">5.3.5</a></li>
+                        <li><em>Section 7.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.15">8.2</a></li>
+                        <li><em>Section 7.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.9">7.3.4</a></li>
                         <li><em>Section 7.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">3.2</a></li>
-                        <li><em>Section 7.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.2">3.5.1</a>, <a href="#rfc.xref.Part6.17">8.2</a></li>
-                        <li><em>Section 7.6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.11">7.3.4</a></li>
+                        <li><em>Section 7.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.10">7.3.4</a></li>
                      </ul>
                   </li>
@@ -5425 +5475 @@
                </ul>
             </li>
+            <li><a id="rfc.index.V" href="#rfc.index.V"><b>V</b></a><ul>
+                  <li>Vary header field&nbsp;&nbsp;<a href="#rfc.xref.header.vary.1">3.5.1</a>, <a href="#rfc.xref.header.vary.2">8.2</a>, <a href="#rfc.iref.v.1"><b>8.2.2</b></a>, <a href="#rfc.xref.header.vary.3">10.3.2</a></li>
+               </ul>
+            </li>
          </ul>
       </div>

draft-ietf-httpbis/latest/p2-semantics.xml

@@ -69 +69 @@
   <!ENTITY header-upgrade             "<xref target='Part1' x:rel='#header.upgrade' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-user-agent          "<xref target='header.user-agent' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
-  <!ENTITY header-vary                "<xref target='Part6' x:rel='#header.vary' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-via                 "<xref target='Part1' x:rel='#header.via' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-warning             "<xref target='Part6' x:rel='#header.warning' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
@@ -802 +801 @@
 </x:note>
 <t>
-   The <x:ref>Vary</x:ref> header field (&header-vary;) can be used to express
-   the parameters the server uses to select a representation that is subject to
-   proactive negotiation.
+   The <x:ref>Vary</x:ref> header field (<xref target="header.vary"/>) can be
+   used to express the parameters the server uses to select a representation
+   that is subject to proactive negotiation.
 </t>
 </section>
@@ -3452 +3451 @@
   <ttcol>Header Field Name</ttcol><ttcol>Defined in...</ttcol>
 
+  <c>Age</c> <c>&header-age;</c>
   <c>Date</c> <c><xref target="header.date"/></c>
-  <c>Age</c> <c>&header-age;</c>
-  <c>Vary</c> <c>&header-vary;</c>
+  <c>Vary</c> <c><xref target="header.vary"/></c>
 </texttable>
 
@@ -3514 +3513 @@
    practice, the date can be generated at any time during the message
    origination without affecting its semantic value.
+</t>
+</section>
+
+<section anchor="header.vary" title="Vary">
+   <iref item="Vary header field" primary="true" x:for-anchor="" />
+   <iref item="Header Fields" primary="true" subitem="Vary" x:for-anchor="" />
+   <x:anchor-alias value="Vary"/>
+<t>
+   The "Vary" header field conveys the set of header fields
+   that were used to select the representation.
+</t>
+<t>
+   Caches use this information as part of determining whether a stored
+   response can be used to satisfy a given request (&caching-neg-resp;).
+</t>
+<t>
+   In uncacheable or stale responses, the Vary field value advises the user
+   agent about the criteria that were used to select the representation.
+</t>
+<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Vary"/>
+  <x:ref>Vary</x:ref> = "*" / 1#<x:ref>field-name</x:ref>
+</artwork></figure>
+<t>
+   The set of header fields named by the Vary field value is known as the
+   selecting header fields.
+</t>
+<t>
+   A server &SHOULD; include a Vary header field with any cacheable response
+   that is subject to proactive negotiation. Doing so allows a cache to
+   properly interpret future requests on that resource and informs the user
+   agent about the presence of negotiation on that resource. A server &MAY;
+   include a Vary header field with a non-cacheable response that is subject
+   to proactive negotiation, since this might provide the user agent with
+   useful information about the dimensions over which the response varies at
+   the time of the response.
+</t>
+<t>
+   A Vary field value of "*" signals that unspecified parameters not limited
+   to the header fields (e.g., the network address of the client), play a
+   role in the selection of the response representation; therefore, a cache
+   cannot determine whether this response is appropriate. A proxy &MUST-NOT;
+   generate the "*" value.
+</t>
+<t>
+   The field-names given are not limited to the set of standard header
+   fields defined by this specification. Field names are case-insensitive.
 </t>
 </section>
@@ -4614 +4659 @@
       <xref target="header.user-agent"/>
    </c>
+   <c>Vary</c>
+   <c>http</c>
+   <c>standard</c>
+   <c>
+      <xref target="header.vary"/>
+   </c>
 </texttable>
 <!--(END)-->
@@ -4893 +4944 @@
     <x:defines>Upgrade</x:defines>
     <x:defines>Via</x:defines>
+    <x:defines>field-name</x:defines>
   </x:source>
 </reference>
@@ -4973 +5025 @@
   </front>
   <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p6-cache-&ID-VERSION;"/>
-  <x:source href="p6-cache.xml" basename="p6-cache">
-    <x:defines>Vary</x:defines>
-  </x:source>
+  <x:source href="p6-cache.xml" basename="p6-cache"/>
 </reference>
 
@@ -5962 +6012 @@
 <x:ref>User-Agent</x:ref> = product *( RWS ( product / comment ) )
 
+<x:ref>Vary</x:ref> = "*" / ( *( "," OWS ) field-name *( OWS "," [ OWS field-name ]
+ ) )
+
 <x:ref>absolute-URI</x:ref> = &lt;absolute-URI, defined in [Part1], Section 2.7&gt;
+
 <x:ref>accept-ext</x:ref> = OWS ";" OWS token [ "=" word ]
 <x:ref>accept-params</x:ref> = weight *accept-ext
@@ -5969 +6023 @@
 
 <x:ref>charset</x:ref> = token
+
 <x:ref>codings</x:ref> = content-coding / "identity" / "*"
 <x:ref>comment</x:ref> = &lt;comment, defined in [Part1], Section 3.2.4&gt;
@@ -5974 +6029 @@
 
 <x:ref>date1</x:ref> = day SP month SP year
+
 <x:ref>date2</x:ref> = day "-" month "-" 2DIGIT
 <x:ref>date3</x:ref> = month SP ( 2DIGIT / ( SP DIGIT ) )
@@ -5994 +6050 @@
 
 <x:ref>expect-name</x:ref> = token
+
 <x:ref>expect-param</x:ref> = expect-name [ BWS "=" BWS expect-value ]
 <x:ref>expect-value</x:ref> = token / quoted-string
@@ -6002 +6059 @@
 
 <x:ref>language-range</x:ref> = &lt;language-range, defined in [RFC4647], Section 2.1&gt;
+
 <x:ref>language-tag</x:ref> = &lt;Language-Tag, defined in [RFC5646], Section 2.1&gt;
 
 <x:ref>mailbox</x:ref> = &lt;mailbox, defined in [RFC5322], Section 3.4&gt;
+
 <x:ref>media-range</x:ref> = ( "*/*" / ( type "/*" ) / ( type "/" subtype ) ) *( OWS
  ";" OWS parameter )
@@ -6026 +6085 @@
 
 <x:ref>parameter</x:ref> = attribute "=" value
+
 <x:ref>partial-URI</x:ref> = &lt;partial-URI, defined in [Part1], Section 2.7&gt;
 <x:ref>product</x:ref> = token [ "/" product-version ]
@@ -6031 +6091 @@
 
 <x:ref>quoted-string</x:ref> = &lt;quoted-string, defined in [Part1], Section 3.2.4&gt;
+
 <x:ref>qvalue</x:ref> = ( "0" [ "." *3DIGIT ] ) / ( "1" [ "." *3"0" ] )
 
 <x:ref>rfc1123-date</x:ref> = day-name "," SP date1 SP time-of-day SP GMT
+
 <x:ref>rfc850-date</x:ref> = day-name-l "," SP date2 SP time-of-day SP GMT
 
 <x:ref>second</x:ref> = 2DIGIT
+
 <x:ref>subtype</x:ref> = token
 
 <x:ref>time-of-day</x:ref> = hour ":" minute ":" second
+
 <x:ref>token</x:ref> = &lt;token, defined in [Part1], Section 3.2.4&gt;
 <x:ref>type</x:ref> = token
@@ -6046 +6110 @@
 
 <x:ref>weight</x:ref> = OWS ";" OWS "q=" qvalue
+
 <x:ref>word</x:ref> = &lt;word, defined in [Part1], Section 3.2.4&gt;
 
@@ -6051 +6116 @@
 </artwork>
 </figure>
-</section>
+<figure><preamble>ABNF diagnostics:</preamble><artwork type="inline">
+; field-name UNDEFINED
+</artwork></figure></section>
 <?ENDINC p2-semantics.abnf-appendix ?>
 

draft-ietf-httpbis/latest/p4-conditional.html

@@ -449 +449 @@
   } 
   @bottom-center {
-       content: "Expires March 5, 2013"; 
+       content: "Expires March 7, 2013"; 
   } 
   @bottom-right {
@@ -492 +492 @@
       <meta name="dct.creator" content="Reschke, J. F.">
       <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p4-conditional-latest">
-      <meta name="dct.issued" scheme="ISO8601" content="2012-09-01">
+      <meta name="dct.issued" scheme="ISO8601" content="2012-09-03">
       <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. This document defines HTTP/1.1 conditional requests, including metadata header fields for indicating state changes, request header fields for making preconditions on such state, and rules for constructing the responses to a conditional request when one or more preconditions evaluate to false.">
@@ -518 +518 @@
             </tr>
             <tr>
-               <td class="left">Expires: March 5, 2013</td>
+               <td class="left">Expires: March 7, 2013</td>
                <td class="right">J. Reschke, Editor</td>
             </tr>
@@ -527 +527 @@
             <tr>
                <td class="left"></td>
-               <td class="right">September 1, 2012</td>
+               <td class="right">September 3, 2012</td>
             </tr>
          </tbody>
@@ -554 +554 @@
          in progress”.
       </p>
-      <p>This Internet-Draft will expire on March 5, 2013.</p>
+      <p>This Internet-Draft will expire on March 7, 2013.</p>
       <h1><a id="rfc.copyrightnotice" href="#rfc.copyrightnotice">Copyright Notice</a></h1>
       <p>Copyright © 2012 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
@@ -884 +884 @@
       </div>
       <h3 id="rfc.section.2.3.3"><a href="#rfc.section.2.3.3">2.3.3</a>&nbsp;<a id="example.entity.tag.vs.conneg" href="#example.entity.tag.vs.conneg">Example: Entity-tags varying on Content-Negotiated Resources</a></h3>
-      <p id="rfc.section.2.3.3.p.1">Consider a resource that is subject to content negotiation (<a href="p2-semantics.html#content.negotiation" title="Content Negotiation">Section 9</a> of <a href="#Part2" id="rfc.xref.Part2.2"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>), and where the representations returned upon a GET request vary based on the <a href="p2-semantics.html#header.accept-encoding" class="smpl">Accept-Encoding</a> request header field (<a href="p2-semantics.html#header.accept-encoding" title="Accept-Encoding">Section 10.3</a> of <a href="#Part2" id="rfc.xref.Part2.3"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>):
+      <p id="rfc.section.2.3.3.p.1">Consider a resource that is subject to content negotiation (<a href="p2-semantics.html#content.negotiation" title="Content Negotiation">Section 3.5</a> of <a href="#Part2" id="rfc.xref.Part2.2"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>), and where the representations returned upon a GET request vary based on the <a href="p2-semantics.html#header.accept-encoding" class="smpl">Accept-Encoding</a> request header field (<a href="p2-semantics.html#header.accept-encoding" title="Accept-Encoding">Section 6.3.4</a> of <a href="#Part2" id="rfc.xref.Part2.3"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>):
       </p>
       <div id="rfc.figure.u.5"></div>
@@ -1093 +1093 @@
          as if it were the payload of a 200 response. The 304 response <em class="bcp14">MUST NOT</em> contain a message-body, and thus is always terminated by the first empty line after the header fields.
       </p>
-      <p id="rfc.section.4.1.p.2">A 304 response <em class="bcp14">MUST</em> include a <a href="p2-semantics.html#header.date" class="smpl">Date</a> header field (<a href="p2-semantics.html#header.date" title="Date">Section 10.10</a> of <a href="#Part2" id="rfc.xref.Part2.4"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>) unless the origin server does not have a clock that can provide a reasonable approximation of the current time. If a <a href="p2-semantics.html#status.200" class="smpl">200
-            (OK)</a> response to the same request would have included any of the header fields <a href="p6-cache.html#header.cache-control" class="smpl">Cache-Control</a>, <a href="p2-semantics.html#header.content-location" class="smpl">Content-Location</a>, <a href="#header.etag" class="smpl">ETag</a>, <a href="p6-cache.html#header.expires" class="smpl">Expires</a>, or <a href="p6-cache.html#header.vary" class="smpl">Vary</a>, then those same header fields <em class="bcp14">MUST</em> be sent in a 304 response.
+      <p id="rfc.section.4.1.p.2">A 304 response <em class="bcp14">MUST</em> include a <a href="p2-semantics.html#header.date" class="smpl">Date</a> header field (<a href="p2-semantics.html#header.date" title="Date">Section 8.2.1</a> of <a href="#Part2" id="rfc.xref.Part2.4"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>) unless the origin server does not have a clock that can provide a reasonable approximation of the current time. If a <a href="p2-semantics.html#status.200" class="smpl">200
+            (OK)</a> response to the same request would have included any of the header fields <a href="p6-cache.html#header.cache-control" class="smpl">Cache-Control</a>, <a href="p2-semantics.html#header.content-location" class="smpl">Content-Location</a>, <a href="#header.etag" class="smpl">ETag</a>, <a href="p6-cache.html#header.expires" class="smpl">Expires</a>, or <a href="p2-semantics.html#header.vary" class="smpl">Vary</a>, then those same header fields <em class="bcp14">MUST</em> be sent in a 304 response.
       </p>
       <p id="rfc.section.4.1.p.3">Since the goal of a 304 response is to minimize information transfer when the recipient already has one or more cached representations,
@@ -1346 +1346 @@
   <a href="#imported.abnf" class="smpl">obs-text</a>      = &lt;obs-text, defined in <a href="#Part1" id="rfc.xref.Part1.9"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
 </pre><p id="rfc.section.B.p.4">The rules below are defined in other parts:</p>
-      <div id="rfc.figure.u.17"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>     = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.5"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 6.1</a>&gt;
+      <div id="rfc.figure.u.17"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>     = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.5"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a>&gt;
 </pre><h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a id="collected.abnf" href="#collected.abnf">Collected ABNF</a></h1>
       <div id="rfc.figure.u.18"></div> <pre class="inline"><a href="#header.etag" class="smpl">ETag</a> = entity-tag
 
-<a href="#imported.abnf" class="smpl">HTTP-date</a> = &lt;HTTP-date, defined in [Part2], Section 6.1&gt;
+<a href="#imported.abnf" class="smpl">HTTP-date</a> = &lt;HTTP-date, defined in [Part2], Section 9.1&gt;
 
 <a href="#header.if-match" class="smpl">If-Match</a> = "*" / ( *( "," OWS ) entity-tag *( OWS "," [ OWS
@@ -1471 +1471 @@
                   </li>
                   <li><em>Part2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">1</a>, <a href="#rfc.xref.Part2.2">2.3.3</a>, <a href="#rfc.xref.Part2.3">2.3.3</a>, <a href="#rfc.xref.Part2.4">4.1</a>, <a href="#Part2"><b>9.1</b></a>, <a href="#rfc.xref.Part2.5">B</a><ul>
-                        <li><em>Section 6.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.5">B</a></li>
-                        <li><em>Section 9</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.2">2.3.3</a></li>
-                        <li><em>Section 10.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.3">2.3.3</a></li>
-                        <li><em>Section 10.10</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.4">4.1</a></li>
+                        <li><em>Section 3.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.2">2.3.3</a></li>
+                        <li><em>Section 6.3.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.3">2.3.3</a></li>
+                        <li><em>Section 8.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.4">4.1</a></li>
+                        <li><em>Section 9.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.5">B</a></li>
                      </ul>
                   </li>

draft-ietf-httpbis/latest/p4-conditional.xml

@@ -28 +28 @@
   <!ENTITY header-if-range            "<xref target='Part5' x:rel='#header.if-range' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-range               "<xref target='Part5' x:rel='#header.range' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
-  <!ENTITY header-vary                "<xref target='Part6' x:rel='#header.vary' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
+  <!ENTITY header-vary                "<xref target='Part2' x:rel='#header.vary' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY http-date                  "<xref target='Part2' x:rel='#http.date' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY transfer-codings           "<xref target='Part1' x:rel='#transfer.codings' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
@@ -1272 +1272 @@
     <x:defines>Date</x:defines>
     <x:defines>Location</x:defines>
+    <x:defines>Vary</x:defines>
   </x:source>
 </reference>
@@ -1324 +1325 @@
     <x:defines>Cache-Control</x:defines>
     <x:defines>Expires</x:defines>
-    <x:defines>Vary</x:defines>
   </x:source>
 </reference>
@@ -1495 +1495 @@
 <x:ref>ETag</x:ref> = entity-tag
 
-<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 6.1&gt;
+<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 9.1&gt;
 
 <x:ref>If-Match</x:ref> = "*" / ( *( "," OWS ) entity-tag *( OWS "," [ OWS

draft-ietf-httpbis/latest/p5-range.html

@@ -449 +449 @@
   } 
   @bottom-center {
-       content: "Expires March 5, 2013"; 
+       content: "Expires March 7, 2013"; 
   } 
   @bottom-right {
@@ -493 +493 @@
       <meta name="dct.creator" content="Reschke, J. F.">
       <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p5-range-latest">
-      <meta name="dct.issued" scheme="ISO8601" content="2012-09-01">
+      <meta name="dct.issued" scheme="ISO8601" content="2012-09-03">
       <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. This document defines range requests and the rules for constructing and combining responses to those requests.">
@@ -519 +519 @@
             </tr>
             <tr>
-               <td class="left">Expires: March 5, 2013</td>
+               <td class="left">Expires: March 7, 2013</td>
                <td class="right">J. Reschke, Editor</td>
             </tr>
@@ -528 +528 @@
             <tr>
                <td class="left"></td>
-               <td class="right">September 1, 2012</td>
+               <td class="right">September 3, 2012</td>
             </tr>
          </tbody>
@@ -553 +553 @@
          in progress”.
       </p>
-      <p>This Internet-Draft will expire on March 5, 2013.</p>
+      <p>This Internet-Draft will expire on March 7, 2013.</p>
       <h1><a id="rfc.copyrightnotice" href="#rfc.copyrightnotice">Copyright Notice</a></h1>
       <p>Copyright © 2012 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
@@ -707 +707 @@
          </li>
          <li>Date</li>
-         <li> <a href="p6-cache.html#header.cache-control" class="smpl">Cache-Control</a>, <a href="p4-conditional.html#header.etag" class="smpl">ETag</a>, <a href="p6-cache.html#header.expires" class="smpl">Expires</a>, <a href="p2-semantics.html#header.content-location" class="smpl">Content-Location</a> and/or <a href="p6-cache.html#header.vary" class="smpl">Vary</a>, if the header field would have been sent in a <a href="p2-semantics.html#status.200" class="smpl">200 (OK)</a> response to the same request
+         <li> <a href="p6-cache.html#header.cache-control" class="smpl">Cache-Control</a>, <a href="p4-conditional.html#header.etag" class="smpl">ETag</a>, <a href="p6-cache.html#header.expires" class="smpl">Expires</a>, <a href="p2-semantics.html#header.content-location" class="smpl">Content-Location</a> and/or <a href="p2-semantics.html#header.vary" class="smpl">Vary</a>, if the header field would have been sent in a <a href="p2-semantics.html#status.200" class="smpl">200 (OK)</a> response to the same request
          </li>
       </ul>
@@ -1270 +1270 @@
   <a href="#imported.abnf" class="smpl">token</a>      = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.6"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
 </pre><p id="rfc.section.C.p.5">The rules below are defined in other parts:</p>
-      <div id="rfc.figure.u.25"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>  = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.1"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 6.1</a>&gt;
+      <div id="rfc.figure.u.25"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>  = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.1"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a>&gt;
   <a href="#imported.abnf" class="smpl">entity-tag</a> = &lt;entity-tag, defined in <a href="#Part4" id="rfc.xref.Part4.5"><cite title="HTTP/1.1, part 4: Conditional Requests">[Part4]</cite></a>, <a href="p4-conditional.html#header.etag" title="ETag">Section 2.3</a>&gt;
 </pre><h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a id="collected.abnf" href="#collected.abnf">Collected ABNF</a></h1>
@@ -1420 +1420 @@
                   </li>
                   <li><em>Part2</em>&nbsp;&nbsp;<a href="#Part2"><b>9.1</b></a>, <a href="#rfc.xref.Part2.1">C</a><ul>
-                        <li><em>Section 6.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">C</a></li>
+                        <li><em>Section 9.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">C</a></li>
                      </ul>
                   </li>

draft-ietf-httpbis/latest/p5-range.xml

@@ -1009 +1009 @@
     <x:defines>Content-Type</x:defines>
     <x:defines>Location</x:defines>
+    <x:defines>Vary</x:defines>
   </x:source>
 </reference>
@@ -1066 +1067 @@
     <x:defines>Cache-Control</x:defines>
     <x:defines>Expires</x:defines>
-    <x:defines>Vary</x:defines>
   </x:source>
 </reference>

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

@@ -650 +650 @@
                <li><a href="#rfc.section.7.3">7.3</a>&nbsp;&nbsp;&nbsp;<a href="#header.expires">Expires</a></li>
                <li><a href="#rfc.section.7.4">7.4</a>&nbsp;&nbsp;&nbsp;<a href="#header.pragma">Pragma</a></li>
-               <li><a href="#rfc.section.7.5">7.5</a>&nbsp;&nbsp;&nbsp;<a href="#header.vary">Vary</a></li>
-               <li><a href="#rfc.section.7.6">7.6</a>&nbsp;&nbsp;&nbsp;<a href="#header.warning">Warning</a><ul>
-                     <li><a href="#rfc.section.7.6.1">7.6.1</a>&nbsp;&nbsp;&nbsp;<a href="#warn.110">110 Response is Stale</a></li>
-                     <li><a href="#rfc.section.7.6.2">7.6.2</a>&nbsp;&nbsp;&nbsp;<a href="#warn.111">111 Revalidation Failed</a></li>
-                     <li><a href="#rfc.section.7.6.3">7.6.3</a>&nbsp;&nbsp;&nbsp;<a href="#warn.112">112 Disconnected Operation</a></li>
-                     <li><a href="#rfc.section.7.6.4">7.6.4</a>&nbsp;&nbsp;&nbsp;<a href="#warn.113">113 Heuristic Expiration</a></li>
-                     <li><a href="#rfc.section.7.6.5">7.6.5</a>&nbsp;&nbsp;&nbsp;<a href="#warn.199">199 Miscellaneous Warning</a></li>
-                     <li><a href="#rfc.section.7.6.6">7.6.6</a>&nbsp;&nbsp;&nbsp;<a href="#warn.214">214 Transformation Applied</a></li>
-                     <li><a href="#rfc.section.7.6.7">7.6.7</a>&nbsp;&nbsp;&nbsp;<a href="#warn.299">299 Miscellaneous Persistent Warning</a></li>
-                     <li><a href="#rfc.section.7.6.8">7.6.8</a>&nbsp;&nbsp;&nbsp;<a href="#warn.code.extensions">Warn Code Extensions</a></li>
+               <li><a href="#rfc.section.7.5">7.5</a>&nbsp;&nbsp;&nbsp;<a href="#header.warning">Warning</a><ul>
+                     <li><a href="#rfc.section.7.5.1">7.5.1</a>&nbsp;&nbsp;&nbsp;<a href="#warn.110">110 Response is Stale</a></li>
+                     <li><a href="#rfc.section.7.5.2">7.5.2</a>&nbsp;&nbsp;&nbsp;<a href="#warn.111">111 Revalidation Failed</a></li>
+                     <li><a href="#rfc.section.7.5.3">7.5.3</a>&nbsp;&nbsp;&nbsp;<a href="#warn.112">112 Disconnected Operation</a></li>
+                     <li><a href="#rfc.section.7.5.4">7.5.4</a>&nbsp;&nbsp;&nbsp;<a href="#warn.113">113 Heuristic Expiration</a></li>
+                     <li><a href="#rfc.section.7.5.5">7.5.5</a>&nbsp;&nbsp;&nbsp;<a href="#warn.199">199 Miscellaneous Warning</a></li>
+                     <li><a href="#rfc.section.7.5.6">7.5.6</a>&nbsp;&nbsp;&nbsp;<a href="#warn.214">214 Transformation Applied</a></li>
+                     <li><a href="#rfc.section.7.5.7">7.5.7</a>&nbsp;&nbsp;&nbsp;<a href="#warn.299">299 Miscellaneous Persistent Warning</a></li>
+                     <li><a href="#rfc.section.7.5.8">7.5.8</a>&nbsp;&nbsp;&nbsp;<a href="#warn.code.extensions">Warn Code Extensions</a></li>
                   </ul>
                </li>
@@ -1066 +1065 @@
          or doing so is explicitly allowed (e.g., by the max-stale request directive; see <a href="#cache-request-directive" title="Request Cache-Control Directives">Section&nbsp;7.2.1</a>).
       </p>
-      <p id="rfc.section.4.1.4.p.4">A cache <em class="bcp14">SHOULD</em> append a <a href="#header.warning" class="smpl">Warning</a> header field with the 110 warn-code (see <a href="#header.warning" id="rfc.xref.header.warning.1" title="Warning">Section&nbsp;7.6</a>) to stale responses. Likewise, a cache <em class="bcp14">SHOULD</em> add the 112 warn-code to stale responses if the cache is disconnected.
+      <p id="rfc.section.4.1.4.p.4">A cache <em class="bcp14">SHOULD</em> append a <a href="#header.warning" class="smpl">Warning</a> header field with the 110 warn-code (see <a href="#header.warning" id="rfc.xref.header.warning.1" title="Warning">Section&nbsp;7.5</a>) to stale responses. Likewise, a cache <em class="bcp14">SHOULD</em> add the 112 warn-code to stale responses if the cache is disconnected.
       </p>
       <p id="rfc.section.4.1.4.p.5">If a cache receives a first-hand response (either an entire response, or a <a href="p4-conditional.html#status.304" class="smpl">304 (Not Modified)</a> response) that it would normally forward to the requesting client, and the received response is no longer fresh, the cache
@@ -1114 +1113 @@
       </p>
       <ul>
-         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.2" title="Warning">Section&nbsp;7.6</a>);
+         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.2" title="Warning">Section&nbsp;7.5</a>);
          </li>
          <li>retain any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 2xx; and,
@@ -1122 +1121 @@
       </ul>
       <h2 id="rfc.section.4.3"><a href="#rfc.section.4.3">4.3</a>&nbsp;<a id="caching.negotiated.responses" href="#caching.negotiated.responses">Using Negotiated Responses</a></h2>
-      <p id="rfc.section.4.3.p.1">When a cache receives a request that can be satisfied by a stored response that has a <a href="#header.vary" class="smpl">Vary</a> header field (<a href="#header.vary" id="rfc.xref.header.vary.1" title="Vary">Section&nbsp;7.5</a>), it <em class="bcp14">MUST NOT</em> use that response unless all of the selecting header fields nominated by the Vary header field match in both the original
+      <p id="rfc.section.4.3.p.1">When a cache receives a request that can be satisfied by a stored response that has a <a href="p2-semantics.html#header.vary" class="smpl">Vary</a> header field (<a href="p2-semantics.html#header.vary" title="Vary">Section 8.2.2</a> of <a href="#Part2" id="rfc.xref.Part2.5"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>), it <em class="bcp14">MUST NOT</em> use that response unless all of the selecting header fields nominated by the Vary header field match in both the original
          request (i.e., that associated with the stored response), and the presented request.
       </p>
@@ -1139 +1138 @@
          if it is also absent there.
       </p>
-      <p id="rfc.section.4.3.p.4">A <a href="#header.vary" class="smpl">Vary</a> header field-value of "*" always fails to match, and subsequent requests to that resource can only be properly interpreted
+      <p id="rfc.section.4.3.p.4">A <a href="p2-semantics.html#header.vary" class="smpl">Vary</a> header field-value of "*" always fails to match, and subsequent requests to that resource can only be properly interpreted
          by the origin server.
       </p>
@@ -1156 +1155 @@
       </p>
       <ul>
-         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.3" title="Warning">Section&nbsp;7.6</a>);
+         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.3" title="Warning">Section&nbsp;7.5</a>);
          </li>
          <li>retain any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 2xx; and,
@@ -1172 +1171 @@
       </p>
       <ul>
-         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.4" title="Warning">Section&nbsp;7.6</a>);
+         <li>delete any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 1xx (see <a href="#header.warning" id="rfc.xref.header.warning.4" title="Warning">Section&nbsp;7.5</a>);
          </li>
          <li>retain any <a href="#header.warning" class="smpl">Warning</a> header fields in the stored response with warn-code 2xx; and,
@@ -1181 +1180 @@
       </ul>
       <h1 id="rfc.section.6"><a href="#rfc.section.6">6.</a>&nbsp;<a id="invalidation.after.updates.or.deletions" href="#invalidation.after.updates.or.deletions">Request Methods that Invalidate</a></h1>
-      <p id="rfc.section.6.p.1">Because unsafe request methods (<a href="p2-semantics.html#safe.methods" title="Safe Methods">Section 5.2.1</a> of <a href="#Part2" id="rfc.xref.Part2.5"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>) such as PUT, POST or DELETE have the potential for changing state on the origin server, intervening caches can use them
+      <p id="rfc.section.6.p.1">Because unsafe request methods (<a href="p2-semantics.html#safe.methods" title="Safe Methods">Section 5.2.1</a> of <a href="#Part2" id="rfc.xref.Part2.6"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>) such as PUT, POST or DELETE have the potential for changing state on the origin server, intervening caches can use them
          to keep their contents up-to-date.
       </p>
@@ -1468 +1467 @@
          that time.
       </p>
-      <p id="rfc.section.7.3.p.3">The field-value is an absolute date and time as defined by HTTP-date in <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a> of <a href="#Part2" id="rfc.xref.Part2.6"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>; a sender <em class="bcp14">MUST</em> use the rfc1123-date format.
+      <p id="rfc.section.7.3.p.3">The field-value is an absolute date and time as defined by HTTP-date in <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a> of <a href="#Part2" id="rfc.xref.Part2.7"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>; a sender <em class="bcp14">MUST</em> use the rfc1123-date format.
       </p>
       <div id="rfc.figure.u.9"></div><pre class="inline"><span id="rfc.iref.g.5"></span>  <a href="#header.expires" class="smpl">Expires</a> = <a href="#imported.abnf" class="smpl">HTTP-date</a>
@@ -1519 +1518 @@
          </p> 
       </div>
-      <div id="rfc.iref.v.3"></div>
+      <div id="rfc.iref.w.1"></div>
       <div id="rfc.iref.h.6"></div>
-      <h2 id="rfc.section.7.5"><a href="#rfc.section.7.5">7.5</a>&nbsp;<a id="header.vary" href="#header.vary">Vary</a></h2>
-      <p id="rfc.section.7.5.p.1">The "Vary" header field conveys the set of header fields that were used to select the representation.</p>
-      <p id="rfc.section.7.5.p.2">Caches use this information, in part, to determine whether a stored response can be used to satisfy a given request; see <a href="#caching.negotiated.responses" title="Using Negotiated Responses">Section&nbsp;4.3</a>.
-      </p>
-      <p id="rfc.section.7.5.p.3">In uncacheable or stale responses, the Vary field value advises the user agent about the criteria that were used to select
-         the representation.
-      </p>
-      <div id="rfc.figure.u.13"></div><pre class="inline"><span id="rfc.iref.g.9"></span>  <a href="#header.vary" class="smpl">Vary</a> = "*" / 1#<a href="#imported.abnf" class="smpl">field-name</a>
-</pre><p id="rfc.section.7.5.p.5">The set of header fields named by the Vary field value is known as the selecting header fields.</p>
-      <p id="rfc.section.7.5.p.6">A server <em class="bcp14">SHOULD</em> include a Vary header field with any cacheable response that is subject to proactive negotiation. Doing so allows a cache
-         to properly interpret future requests on that resource and informs the user agent about the presence of negotiation on that
-         resource. A server <em class="bcp14">MAY</em> include a Vary header field with a non-cacheable response that is subject to proactive negotiation, since this might provide
-         the user agent with useful information about the dimensions over which the response varies at the time of the response.
-      </p>
-      <p id="rfc.section.7.5.p.7">A Vary field value of "*" signals that unspecified parameters not limited to the header fields (e.g., the network address
-         of the client), play a role in the selection of the response representation; therefore, a cache cannot determine whether this
-         response is appropriate. A proxy <em class="bcp14">MUST NOT</em> generate the "*" value.
-      </p>
-      <p id="rfc.section.7.5.p.8">The field-names given are not limited to the set of standard header fields defined by this specification. Field names are
-         case-insensitive.
-      </p>
-      <div id="rfc.iref.w.1"></div>
-      <div id="rfc.iref.h.7"></div>
-      <h2 id="rfc.section.7.6"><a href="#rfc.section.7.6">7.6</a>&nbsp;<a id="header.warning" href="#header.warning">Warning</a></h2>
-      <p id="rfc.section.7.6.p.1">The "Warning" header field is used to carry additional information about the status or transformation of a message that might
+      <h2 id="rfc.section.7.5"><a href="#rfc.section.7.5">7.5</a>&nbsp;<a id="header.warning" href="#header.warning">Warning</a></h2>
+      <p id="rfc.section.7.5.p.1">The "Warning" header field is used to carry additional information about the status or transformation of a message that might
          not be reflected in the message. This information is typically used to warn about possible incorrectness introduced by caching
          operations or transformations applied to the payload of the message.
       </p>
-      <p id="rfc.section.7.6.p.2">Warnings can be used for other purposes, both cache-related and otherwise. The use of a warning, rather than an error status
+      <p id="rfc.section.7.5.p.2">Warnings can be used for other purposes, both cache-related and otherwise. The use of a warning, rather than an error status
          code, distinguishes these responses from true failures.
       </p>
-      <p id="rfc.section.7.6.p.3">Warning header fields can in general be applied to any message, however some warn-codes are specific to caches and can only
+      <p id="rfc.section.7.5.p.3">Warning header fields can in general be applied to any message, however some warn-codes are specific to caches and can only
          be applied to response messages.
       </p>
-      <div id="rfc.figure.u.14"></div><pre class="inline"><span id="rfc.iref.g.10"></span><span id="rfc.iref.g.11"></span><span id="rfc.iref.g.12"></span><span id="rfc.iref.g.13"></span><span id="rfc.iref.g.14"></span><span id="rfc.iref.g.15"></span>  <a href="#header.warning" class="smpl">Warning</a>       = 1#<a href="#header.warning" class="smpl">warning-value</a>
+      <div id="rfc.figure.u.13"></div><pre class="inline"><span id="rfc.iref.g.9"></span><span id="rfc.iref.g.10"></span><span id="rfc.iref.g.11"></span><span id="rfc.iref.g.12"></span><span id="rfc.iref.g.13"></span><span id="rfc.iref.g.14"></span>  <a href="#header.warning" class="smpl">Warning</a>       = 1#<a href="#header.warning" class="smpl">warning-value</a>
   
   <a href="#header.warning" class="smpl">warning-value</a> = <a href="#header.warning" class="smpl">warn-code</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#header.warning" class="smpl">warn-agent</a> <a href="#imported.abnf" class="smpl">SP</a> <a href="#header.warning" class="smpl">warn-text</a>
@@ -1566 +1542 @@
   <a href="#header.warning" class="smpl">warn-text</a>  = <a href="#imported.abnf" class="smpl">quoted-string</a>
   <a href="#header.warning" class="smpl">warn-date</a>  = <a href="#imported.abnf" class="smpl">DQUOTE</a> <a href="#imported.abnf" class="smpl">HTTP-date</a> <a href="#imported.abnf" class="smpl">DQUOTE</a>
-</pre><p id="rfc.section.7.6.p.5">Multiple warnings can be attached to a response (either by the origin server or by a cache), including multiple warnings with
+</pre><p id="rfc.section.7.5.p.5">Multiple warnings can be attached to a response (either by the origin server or by a cache), including multiple warnings with
          the same code number, only differing in warn-text.
       </p>
-      <p id="rfc.section.7.6.p.6">When this occurs, the user agent <em class="bcp14">SHOULD</em> inform the user of as many of them as possible, in the order that they appear in the response.
-      </p>
-      <p id="rfc.section.7.6.p.7">Systems that generate multiple Warning header fields are encouraged to order them with this user agent behavior in mind. New
+      <p id="rfc.section.7.5.p.6">When this occurs, the user agent <em class="bcp14">SHOULD</em> inform the user of as many of them as possible, in the order that they appear in the response.
+      </p>
+      <p id="rfc.section.7.5.p.7">Systems that generate multiple Warning header fields are encouraged to order them with this user agent behavior in mind. New
          Warning header fields are added after any existing Warning header fields.
       </p>
-      <p id="rfc.section.7.6.p.8">Warnings are assigned three digit warn-codes. The first digit indicates whether the Warning is required to be deleted from
+      <p id="rfc.section.7.5.p.8">Warnings are assigned three digit warn-codes. The first digit indicates whether the Warning is required to be deleted from
          a stored response after validation: 
       </p>
@@ -1584 +1560 @@
          </li>
       </ul>
-      <p id="rfc.section.7.6.p.9">If an implementation sends a message with one or more Warning header fields to a receiver whose version is HTTP/1.0 or lower,
+      <p id="rfc.section.7.5.p.9">If an implementation sends a message with one or more Warning header fields to a receiver whose version is HTTP/1.0 or lower,
          then the sender <em class="bcp14">MUST</em> include in each warning-value a warn-date that matches the <a href="p2-semantics.html#header.date" class="smpl">Date</a> header field in the message.
       </p>
-      <p id="rfc.section.7.6.p.10">If a system receives a message with a warning-value that includes a warn-date, and that warn-date is different from the <a href="p2-semantics.html#header.date" class="smpl">Date</a> value in the response, then that warning-value <em class="bcp14">MUST</em> be deleted from the message before storing, forwarding, or using it. (preventing the consequences of naive caching of Warning
+      <p id="rfc.section.7.5.p.10">If a system receives a message with a warning-value that includes a warn-date, and that warn-date is different from the <a href="p2-semantics.html#header.date" class="smpl">Date</a> value in the response, then that warning-value <em class="bcp14">MUST</em> be deleted from the message before storing, forwarding, or using it. (preventing the consequences of naive caching of Warning
          header fields.) If all of the warning-values are deleted for this reason, the Warning header field <em class="bcp14">MUST</em> be deleted as well.
       </p>
-      <p id="rfc.section.7.6.p.11">The following warn-codes are defined by this specification, each with a recommended warn-text in English, and a description
+      <p id="rfc.section.7.5.p.11">The following warn-codes are defined by this specification, each with a recommended warn-text in English, and a description
          of its meaning.
       </p>
+      <div id="rfc.iref.73"></div>
+      <div id="rfc.iref.w.2"></div>
+      <h3 id="rfc.section.7.5.1"><a href="#rfc.section.7.5.1">7.5.1</a>&nbsp;<a id="warn.110" href="#warn.110">110 Response is Stale</a></h3>
+      <p id="rfc.section.7.5.1.p.1">A cache <em class="bcp14">SHOULD</em> include this whenever the returned response is stale.
+      </p>
+      <div id="rfc.iref.74"></div>
+      <div id="rfc.iref.w.3"></div>
+      <h3 id="rfc.section.7.5.2"><a href="#rfc.section.7.5.2">7.5.2</a>&nbsp;<a id="warn.111" href="#warn.111">111 Revalidation Failed</a></h3>
+      <p id="rfc.section.7.5.2.p.1">A cache <em class="bcp14">SHOULD</em> include this when returning a stale response because an attempt to validate the response failed, due to an inability to reach
+         the server.
+      </p>
+      <div id="rfc.iref.75"></div>
+      <div id="rfc.iref.w.4"></div>
+      <h3 id="rfc.section.7.5.3"><a href="#rfc.section.7.5.3">7.5.3</a>&nbsp;<a id="warn.112" href="#warn.112">112 Disconnected Operation</a></h3>
+      <p id="rfc.section.7.5.3.p.1">A cache <em class="bcp14">SHOULD</em> include this if it is intentionally disconnected from the rest of the network for a period of time.
+      </p>
       <div id="rfc.iref.76"></div>
-      <div id="rfc.iref.w.2"></div>
-      <h3 id="rfc.section.7.6.1"><a href="#rfc.section.7.6.1">7.6.1</a>&nbsp;<a id="warn.110" href="#warn.110">110 Response is Stale</a></h3>
-      <p id="rfc.section.7.6.1.p.1">A cache <em class="bcp14">SHOULD</em> include this whenever the returned response is stale.
+      <div id="rfc.iref.w.5"></div>
+      <h3 id="rfc.section.7.5.4"><a href="#rfc.section.7.5.4">7.5.4</a>&nbsp;<a id="warn.113" href="#warn.113">113 Heuristic Expiration</a></h3>
+      <p id="rfc.section.7.5.4.p.1">A cache <em class="bcp14">SHOULD</em> include this if it heuristically chose a freshness lifetime greater than 24 hours and the response's age is greater than 24
+         hours.
       </p>
       <div id="rfc.iref.77"></div>
-      <div id="rfc.iref.w.3"></div>
-      <h3 id="rfc.section.7.6.2"><a href="#rfc.section.7.6.2">7.6.2</a>&nbsp;<a id="warn.111" href="#warn.111">111 Revalidation Failed</a></h3>
-      <p id="rfc.section.7.6.2.p.1">A cache <em class="bcp14">SHOULD</em> include this when returning a stale response because an attempt to validate the response failed, due to an inability to reach
-         the server.
+      <div id="rfc.iref.w.6"></div>
+      <h3 id="rfc.section.7.5.5"><a href="#rfc.section.7.5.5">7.5.5</a>&nbsp;<a id="warn.199" href="#warn.199">199 Miscellaneous Warning</a></h3>
+      <p id="rfc.section.7.5.5.p.1">The warning text can include arbitrary information to be presented to a human user, or logged. A system receiving this warning <em class="bcp14">MUST NOT</em> take any automated action, besides presenting the warning to the user.
       </p>
       <div id="rfc.iref.78"></div>
-      <div id="rfc.iref.w.4"></div>
-      <h3 id="rfc.section.7.6.3"><a href="#rfc.section.7.6.3">7.6.3</a>&nbsp;<a id="warn.112" href="#warn.112">112 Disconnected Operation</a></h3>
-      <p id="rfc.section.7.6.3.p.1">A cache <em class="bcp14">SHOULD</em> include this if it is intentionally disconnected from the rest of the network for a period of time.
+      <div id="rfc.iref.w.7"></div>
+      <h3 id="rfc.section.7.5.6"><a href="#rfc.section.7.5.6">7.5.6</a>&nbsp;<a id="warn.214" href="#warn.214">214 Transformation Applied</a></h3>
+      <p id="rfc.section.7.5.6.p.1"> <em class="bcp14">MUST</em> be added by a proxy if it applies any transformation to the representation, such as changing the content-coding, media-type,
+         or modifying the representation data, unless this Warning code already appears in the response.
       </p>
       <div id="rfc.iref.79"></div>
-      <div id="rfc.iref.w.5"></div>
-      <h3 id="rfc.section.7.6.4"><a href="#rfc.section.7.6.4">7.6.4</a>&nbsp;<a id="warn.113" href="#warn.113">113 Heuristic Expiration</a></h3>
-      <p id="rfc.section.7.6.4.p.1">A cache <em class="bcp14">SHOULD</em> include this if it heuristically chose a freshness lifetime greater than 24 hours and the response's age is greater than 24
-         hours.
-      </p>
-      <div id="rfc.iref.80"></div>
-      <div id="rfc.iref.w.6"></div>
-      <h3 id="rfc.section.7.6.5"><a href="#rfc.section.7.6.5">7.6.5</a>&nbsp;<a id="warn.199" href="#warn.199">199 Miscellaneous Warning</a></h3>
-      <p id="rfc.section.7.6.5.p.1">The warning text can include arbitrary information to be presented to a human user, or logged. A system receiving this warning <em class="bcp14">MUST NOT</em> take any automated action, besides presenting the warning to the user.
-      </p>
-      <div id="rfc.iref.81"></div>
-      <div id="rfc.iref.w.7"></div>
-      <h3 id="rfc.section.7.6.6"><a href="#rfc.section.7.6.6">7.6.6</a>&nbsp;<a id="warn.214" href="#warn.214">214 Transformation Applied</a></h3>
-      <p id="rfc.section.7.6.6.p.1"> <em class="bcp14">MUST</em> be added by a proxy if it applies any transformation to the representation, such as changing the content-coding, media-type,
-         or modifying the representation data, unless this Warning code already appears in the response.
-      </p>
-      <div id="rfc.iref.82"></div>
       <div id="rfc.iref.w.8"></div>
-      <h3 id="rfc.section.7.6.7"><a href="#rfc.section.7.6.7">7.6.7</a>&nbsp;<a id="warn.299" href="#warn.299">299 Miscellaneous Persistent Warning</a></h3>
-      <p id="rfc.section.7.6.7.p.1">The warning text can include arbitrary information to be presented to a human user, or logged. A system receiving this warning <em class="bcp14">MUST NOT</em> take any automated action.
-      </p>
-      <h3 id="rfc.section.7.6.8"><a href="#rfc.section.7.6.8">7.6.8</a>&nbsp;<a id="warn.code.extensions" href="#warn.code.extensions">Warn Code Extensions</a></h3>
-      <p id="rfc.section.7.6.8.p.1">The HTTP Warn Code Registry defines the name space for warn codes.</p>
-      <p id="rfc.section.7.6.8.p.2">A registration <em class="bcp14">MUST</em> include the following fields: 
+      <h3 id="rfc.section.7.5.7"><a href="#rfc.section.7.5.7">7.5.7</a>&nbsp;<a id="warn.299" href="#warn.299">299 Miscellaneous Persistent Warning</a></h3>
+      <p id="rfc.section.7.5.7.p.1">The warning text can include arbitrary information to be presented to a human user, or logged. A system receiving this warning <em class="bcp14">MUST NOT</em> take any automated action.
+      </p>
+      <h3 id="rfc.section.7.5.8"><a href="#rfc.section.7.5.8">7.5.8</a>&nbsp;<a id="warn.code.extensions" href="#warn.code.extensions">Warn Code Extensions</a></h3>
+      <p id="rfc.section.7.5.8.p.1">The HTTP Warn Code Registry defines the name space for warn codes.</p>
+      <p id="rfc.section.7.5.8.p.2">A registration <em class="bcp14">MUST</em> include the following fields: 
       </p>
       <ul>
@@ -1640 +1616 @@
          <li>Pointer to specification text</li>
       </ul>
-      <p id="rfc.section.7.6.8.p.3">Values to be added to this name space require IETF Review (see <a href="#RFC5226" id="rfc.xref.RFC5226.2"><cite title="Guidelines for Writing an IANA Considerations Section in RFCs">[RFC5226]</cite></a>, <a href="http://tools.ietf.org/html/rfc5226#section-4.1">Section 4.1</a>).
-      </p>
-      <p id="rfc.section.7.6.8.p.4">The registry itself is maintained at &lt;<a href="http://www.iana.org/assignments/http-warn-codes">http://www.iana.org/assignments/http-warn-codes</a>&gt;.
+      <p id="rfc.section.7.5.8.p.3">Values to be added to this name space require IETF Review (see <a href="#RFC5226" id="rfc.xref.RFC5226.2"><cite title="Guidelines for Writing an IANA Considerations Section in RFCs">[RFC5226]</cite></a>, <a href="http://tools.ietf.org/html/rfc5226#section-4.1">Section 4.1</a>).
+      </p>
+      <p id="rfc.section.7.5.8.p.4">The registry itself is maintained at &lt;<a href="http://www.iana.org/assignments/http-warn-codes">http://www.iana.org/assignments/http-warn-codes</a>&gt;.
       </p>
       <h1 id="rfc.section.8"><a href="#rfc.section.8">8.</a>&nbsp;<a id="history.lists" href="#history.lists">History Lists</a></h1>
@@ -1744 +1720 @@
       </div>
       <h2 id="rfc.section.9.2"><a href="#rfc.section.9.2">9.2</a>&nbsp;<a id="warn.code.registration" href="#warn.code.registration">Warn Code Registry</a></h2>
-      <p id="rfc.section.9.2.p.1">The registration procedure for HTTP Warn Codes is defined by <a href="#warn.code.extensions" title="Warn Code Extensions">Section&nbsp;7.6.8</a> of this document.
+      <p id="rfc.section.9.2.p.1">The registration procedure for HTTP Warn Codes is defined by <a href="#warn.code.extensions" title="Warn Code Extensions">Section&nbsp;7.5.8</a> of this document.
       </p>
       <p id="rfc.section.9.2.p.2">The HTTP Warn Code Registry shall be created at &lt;<a href="http://www.iana.org/assignments/http-cache-directives">http://www.iana.org/assignments/http-cache-directives</a>&gt; and be populated with the registrations below:
@@ -1762 +1738 @@
                   <td class="left">110</td>
                   <td class="left">Response is Stale</td>
-                  <td class="left"> <a href="#warn.110" id="rfc.xref.warn.110.1" title="110 Response is Stale">Section&nbsp;7.6.1</a> 
+                  <td class="left"> <a href="#warn.110" id="rfc.xref.warn.110.1" title="110 Response is Stale">Section&nbsp;7.5.1</a> 
                   </td>
                </tr>
@@ -1768 +1744 @@
                   <td class="left">111</td>
                   <td class="left">Revalidation Failed</td>
-                  <td class="left"> <a href="#warn.111" id="rfc.xref.warn.111.1" title="111 Revalidation Failed">Section&nbsp;7.6.2</a> 
+                  <td class="left"> <a href="#warn.111" id="rfc.xref.warn.111.1" title="111 Revalidation Failed">Section&nbsp;7.5.2</a> 
                   </td>
                </tr>
@@ -1774 +1750 @@
                   <td class="left">112</td>
                   <td class="left">Disconnected Operation</td>
-                  <td class="left"> <a href="#warn.112" id="rfc.xref.warn.112.1" title="112 Disconnected Operation">Section&nbsp;7.6.3</a> 
+                  <td class="left"> <a href="#warn.112" id="rfc.xref.warn.112.1" title="112 Disconnected Operation">Section&nbsp;7.5.3</a> 
                   </td>
                </tr>
@@ -1780 +1756 @@
                   <td class="left">113</td>
                   <td class="left">Heuristic Expiration</td>
-                  <td class="left"> <a href="#warn.113" id="rfc.xref.warn.113.1" title="113 Heuristic Expiration">Section&nbsp;7.6.4</a> 
+                  <td class="left"> <a href="#warn.113" id="rfc.xref.warn.113.1" title="113 Heuristic Expiration">Section&nbsp;7.5.4</a> 
                   </td>
                </tr>
@@ -1786 +1762 @@
                   <td class="left">199</td>
                   <td class="left">Miscellaneous Warning</td>
-                  <td class="left"> <a href="#warn.199" id="rfc.xref.warn.199.1" title="199 Miscellaneous Warning">Section&nbsp;7.6.5</a> 
+                  <td class="left"> <a href="#warn.199" id="rfc.xref.warn.199.1" title="199 Miscellaneous Warning">Section&nbsp;7.5.5</a> 
                   </td>
                </tr>
@@ -1792 +1768 @@
                   <td class="left">214</td>
                   <td class="left">Transformation Applied</td>
-                  <td class="left"> <a href="#warn.214" id="rfc.xref.warn.214.1" title="214 Transformation Applied">Section&nbsp;7.6.6</a> 
+                  <td class="left"> <a href="#warn.214" id="rfc.xref.warn.214.1" title="214 Transformation Applied">Section&nbsp;7.5.6</a> 
                   </td>
                </tr>
@@ -1798 +1774 @@
                   <td class="left">299</td>
                   <td class="left">Miscellaneous Persistent Warning</td>
-                  <td class="left"> <a href="#warn.299" id="rfc.xref.warn.299.1" title="299 Miscellaneous Persistent Warning">Section&nbsp;7.6.7</a> 
+                  <td class="left"> <a href="#warn.299" id="rfc.xref.warn.299.1" title="299 Miscellaneous Persistent Warning">Section&nbsp;7.5.7</a> 
                   </td>
                </tr>
@@ -1848 +1824 @@
                </tr>
                <tr>
-                  <td class="left">Vary</td>
-                  <td class="left">http</td>
-                  <td class="left">standard</td>
-                  <td class="left"> <a href="#header.vary" id="rfc.xref.header.vary.2" title="Vary">Section&nbsp;7.5</a> 
-                  </td>
-               </tr>
-               <tr>
                   <td class="left">Warning</td>
                   <td class="left">http</td>
                   <td class="left">standard</td>
-                  <td class="left"> <a href="#header.warning" id="rfc.xref.header.warning.5" title="Warning">Section&nbsp;7.6</a> 
+                  <td class="left"> <a href="#header.warning" id="rfc.xref.header.warning.5" title="Warning">Section&nbsp;7.5</a> 
                   </td>
                </tr>
@@ -1968 +1937 @@
       <p id="rfc.section.A.p.4">Change ABNF productions for header fields to only define the field value. (<a href="#header.field.definitions" title="Header Field Definitions">Section&nbsp;7</a>)
       </p>
-      <p id="rfc.section.A.p.5">Do not mention RFC 2047 encoding and multiple languages in <a href="#header.warning" class="smpl">Warning</a> header fields anymore, as these aspects never were implemented. (<a href="#header.warning" id="rfc.xref.header.warning.6" title="Warning">Section&nbsp;7.6</a>)
-      </p>
-      <p id="rfc.section.A.p.6">Introduce Cache Directive and Warn Code Registries. (<a href="#cache.control.extensions" title="Cache Control Extensions">Section&nbsp;7.2.3</a> and <a href="#warn.code.extensions" title="Warn Code Extensions">Section&nbsp;7.6.8</a>)
+      <p id="rfc.section.A.p.5">Do not mention RFC 2047 encoding and multiple languages in <a href="#header.warning" class="smpl">Warning</a> header fields anymore, as these aspects never were implemented. (<a href="#header.warning" id="rfc.xref.header.warning.6" title="Warning">Section&nbsp;7.5</a>)
+      </p>
+      <p id="rfc.section.A.p.6">Introduce Cache Directive and Warn Code Registries. (<a href="#cache.control.extensions" title="Cache Control Extensions">Section&nbsp;7.2.3</a> and <a href="#warn.code.extensions" title="Warn Code Extensions">Section&nbsp;7.5.8</a>)
       </p>
       <h1 id="rfc.section.B"><a href="#rfc.section.B">B.</a>&nbsp;<a id="imported.abnf" href="#imported.abnf">Imported ABNF</a></h1>
@@ -1979 +1948 @@
       <p id="rfc.section.B.p.2">The rules below are defined in <a href="#Part1" id="rfc.xref.Part1.10"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>:
       </p>
-      <div id="rfc.figure.u.15"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
+      <div id="rfc.figure.u.14"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
   <a href="#imported.abnf" class="smpl">field-name</a>    = &lt;field-name, defined in <a href="#Part1" id="rfc.xref.Part1.12"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a>&gt;
   <a href="#imported.abnf" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.13"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
@@ -1988 +1957 @@
   <a href="#imported.abnf" class="smpl">uri-host</a>      = &lt;uri-host, defined in <a href="#Part1" id="rfc.xref.Part1.17"><cite title="HTTP/1.1, part 1: Message Routing and Syntax&#34;">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.7</a>&gt;
 </pre><p id="rfc.section.B.p.4">The rules below are defined in other parts:</p>
-      <div id="rfc.figure.u.16"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>     = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.7"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a>&gt;
+      <div id="rfc.figure.u.15"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">HTTP-date</a>     = &lt;HTTP-date, defined in <a href="#Part2" id="rfc.xref.Part2.8"><cite title="HTTP/1.1, part 2: Semantics and Payloads">[Part2]</cite></a>, <a href="p2-semantics.html#http.date" title="Date/Time Formats">Section 9.1</a>&gt;
 </pre><h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a id="collected.abnf" href="#collected.abnf">Collected ABNF</a></h1>
-      <div id="rfc.figure.u.17"></div> <pre class="inline"><a href="#header.age" class="smpl">Age</a> = delta-seconds
+      <div id="rfc.figure.u.16"></div> <pre class="inline"><a href="#header.age" class="smpl">Age</a> = delta-seconds
 
 <a href="#header.cache-control" class="smpl">Cache-Control</a> = *( "," OWS ) cache-directive *( OWS "," [ OWS
@@ -1997 +1966 @@
 <a href="#header.expires" class="smpl">Expires</a> = HTTP-date
 
-<a href="#imported.abnf" class="smpl">HTTP-date</a> = &lt;HTTP-date, defined in [Part2], Section 6.1&gt;
+<a href="#imported.abnf" class="smpl">HTTP-date</a> = &lt;HTTP-date, defined in [Part2], Section 9.1&gt;
 
 <a href="#imported.abnf" class="smpl">OWS</a> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
@@ -2003 +1972 @@
 <a href="#header.pragma" class="smpl">Pragma</a> = *( "," OWS ) pragma-directive *( OWS "," [ OWS
  pragma-directive ] )
-
-<a href="#header.vary" class="smpl">Vary</a> = "*" / ( *( "," OWS ) field-name *( OWS "," [ OWS field-name ]
- ) )
 
 <a href="#header.warning" class="smpl">Warning</a> = *( "," OWS ) warning-value *( OWS "," [ OWS warning-value ]
@@ -2034 +2000 @@
 <a href="#header.warning" class="smpl">warning-value</a> = warn-code SP warn-agent SP warn-text [ SP warn-date
  ]
-</pre> <h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a id="change.log" href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
+</pre> <div id="rfc.figure.u.17"></div>
+      <p>ABNF diagnostics:</p><pre class="inline">; field-name defined but not used
+</pre><h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a id="change.log" href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
       <p id="rfc.section.D.p.1">Changes up to the first Working Group Last Call draft are summarized in &lt;<a href="http://trac.tools.ietf.org/html/draft-ietf-httpbis-p6-cache-19#appendix-C">http://trac.tools.ietf.org/html/draft-ietf-httpbis-p6-cache-19#appendix-C</a>&gt;.
       </p>
@@ -2069 +2037 @@
          <ul class="ind">
             <li><a id="rfc.index.1" href="#rfc.index.1"><b>1</b></a><ul>
-                  <li>110 Response is Stale (warn code)&nbsp;&nbsp;<a href="#rfc.iref.76"><b>7.6.1</b></a>, <a href="#rfc.xref.warn.110.1">9.2</a></li>
-                  <li>111 Revalidation Failed (warn code)&nbsp;&nbsp;<a href="#rfc.iref.77"><b>7.6.2</b></a>, <a href="#rfc.xref.warn.111.1">9.2</a></li>
-                  <li>112 Disconnected Operation (warn code)&nbsp;&nbsp;<a href="#rfc.iref.78"><b>7.6.3</b></a>, <a href="#rfc.xref.warn.112.1">9.2</a></li>
-                  <li>113 Heuristic Expiration (warn code)&nbsp;&nbsp;<a href="#rfc.iref.79"><b>7.6.4</b></a>, <a href="#rfc.xref.warn.113.1">9.2</a></li>
-                  <li>199 Miscellaneous Warning (warn code)&nbsp;&nbsp;<a href="#rfc.iref.80"><b>7.6.5</b></a>, <a href="#rfc.xref.warn.199.1">9.2</a></li>
+                  <li>110 Response is Stale (warn code)&nbsp;&nbsp;<a href="#rfc.iref.73"><b>7.5.1</b></a>, <a href="#rfc.xref.warn.110.1">9.2</a></li>
+                  <li>111 Revalidation Failed (warn code)&nbsp;&nbsp;<a href="#rfc.iref.74"><b>7.5.2</b></a>, <a href="#rfc.xref.warn.111.1">9.2</a></li>
+                  <li>112 Disconnected Operation (warn code)&nbsp;&nbsp;<a href="#rfc.iref.75"><b>7.5.3</b></a>, <a href="#rfc.xref.warn.112.1">9.2</a></li>
+                  <li>113 Heuristic Expiration (warn code)&nbsp;&nbsp;<a href="#rfc.iref.76"><b>7.5.4</b></a>, <a href="#rfc.xref.warn.113.1">9.2</a></li>
+                  <li>199 Miscellaneous Warning (warn code)&nbsp;&nbsp;<a href="#rfc.iref.77"><b>7.5.5</b></a>, <a href="#rfc.xref.warn.199.1">9.2</a></li>
                </ul>
             </li>
             <li><a id="rfc.index.2" href="#rfc.index.2"><b>2</b></a><ul>
-                  <li>214 Transformation Applied (warn code)&nbsp;&nbsp;<a href="#rfc.iref.81"><b>7.6.6</b></a>, <a href="#rfc.xref.warn.214.1">9.2</a></li>
-                  <li>299 Miscellaneous Persistent Warning (warn code)&nbsp;&nbsp;<a href="#rfc.iref.82"><b>7.6.7</b></a>, <a href="#rfc.xref.warn.299.1">9.2</a></li>
+                  <li>214 Transformation Applied (warn code)&nbsp;&nbsp;<a href="#rfc.iref.78"><b>7.5.6</b></a>, <a href="#rfc.xref.warn.214.1">9.2</a></li>
+                  <li>299 Miscellaneous Persistent Warning (warn code)&nbsp;&nbsp;<a href="#rfc.iref.79"><b>7.5.7</b></a>, <a href="#rfc.xref.warn.299.1">9.2</a></li>
                </ul>
             </li>
@@ -2132 +2100 @@
                         <li><tt>Pragma</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.6"><b>7.4</b></a></li>
                         <li><tt>pragma-directive</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.7"><b>7.4</b></a></li>
-                        <li><tt>Vary</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.9"><b>7.5</b></a></li>
-                        <li><tt>warn-agent</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.13"><b>7.6</b></a></li>
-                        <li><tt>warn-code</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.12"><b>7.6</b></a></li>
-                        <li><tt>warn-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.15"><b>7.6</b></a></li>
-                        <li><tt>warn-text</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.14"><b>7.6</b></a></li>
-                        <li><tt>Warning</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.10"><b>7.6</b></a></li>
-                        <li><tt>warning-value</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.11"><b>7.6</b></a></li>
+                        <li><tt>warn-agent</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.12"><b>7.5</b></a></li>
+                        <li><tt>warn-code</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.11"><b>7.5</b></a></li>
+                        <li><tt>warn-date</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.14"><b>7.5</b></a></li>
+                        <li><tt>warn-text</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.13"><b>7.5</b></a></li>
+                        <li><tt>Warning</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.9"><b>7.5</b></a></li>
+                        <li><tt>warning-value</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.10"><b>7.5</b></a></li>
                      </ul>
                   </li>
@@ -2150 +2117 @@
                         <li>Expires&nbsp;&nbsp;<a href="#rfc.xref.header.expires.1">3</a>, <a href="#rfc.xref.header.expires.2">4.1</a>, <a href="#rfc.xref.header.expires.3">4.1.1</a>, <a href="#rfc.iref.h.4"><b>7.3</b></a>, <a href="#rfc.xref.header.expires.4">9.3</a></li>
                         <li>Pragma&nbsp;&nbsp;<a href="#rfc.xref.header.pragma.1">4</a>, <a href="#rfc.xref.header.pragma.2">7.2</a>, <a href="#rfc.iref.h.5"><b>7.4</b></a>, <a href="#rfc.xref.header.pragma.3">9.3</a></li>
-                        <li>Vary&nbsp;&nbsp;<a href="#rfc.xref.header.vary.1">4.3</a>, <a href="#rfc.iref.h.6"><b>7.5</b></a>, <a href="#rfc.xref.header.vary.2">9.3</a></li>
-                        <li>Warning&nbsp;&nbsp;<a href="#rfc.xref.header.warning.1">4.1.4</a>, <a href="#rfc.xref.header.warning.2">4.2.1</a>, <a href="#rfc.xref.header.warning.3">4.4</a>, <a href="#rfc.xref.header.warning.4">5</a>, <a href="#rfc.iref.h.7"><b>7.6</b></a>, <a href="#rfc.xref.header.warning.5">9.3</a>, <a href="#rfc.xref.header.warning.6">A</a></li>
+                        <li>Warning&nbsp;&nbsp;<a href="#rfc.xref.header.warning.1">4.1.4</a>, <a href="#rfc.xref.header.warning.2">4.2.1</a>, <a href="#rfc.xref.header.warning.3">4.4</a>, <a href="#rfc.xref.header.warning.4">5</a>, <a href="#rfc.iref.h.6"><b>7.5</b></a>, <a href="#rfc.xref.header.warning.5">9.3</a>, <a href="#rfc.xref.header.warning.6">A</a></li>
                      </ul>
                   </li>
@@ -2219 +2185 @@
                      </ul>
                   </li>
-                  <li><em>Part2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">2</a>, <a href="#rfc.xref.Part2.2">4</a>, <a href="#rfc.xref.Part2.3">4.1.2</a>, <a href="#rfc.xref.Part2.4">4.1.3</a>, <a href="#rfc.xref.Part2.5">6</a>, <a href="#rfc.xref.Part2.6">7.3</a>, <a href="#Part2"><b>12.1</b></a>, <a href="#rfc.xref.Part2.7">B</a><ul>
-                        <li><em>Section 5.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.2">4</a>, <a href="#rfc.xref.Part2.5">6</a></li>
+                  <li><em>Part2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">2</a>, <a href="#rfc.xref.Part2.2">4</a>, <a href="#rfc.xref.Part2.3">4.1.2</a>, <a href="#rfc.xref.Part2.4">4.1.3</a>, <a href="#rfc.xref.Part2.5">4.3</a>, <a href="#rfc.xref.Part2.6">6</a>, <a href="#rfc.xref.Part2.7">7.3</a>, <a href="#Part2"><b>12.1</b></a>, <a href="#rfc.xref.Part2.8">B</a><ul>
+                        <li><em>Section 5.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.2">4</a>, <a href="#rfc.xref.Part2.6">6</a></li>
                         <li><em>Section 7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.3">4.1.2</a></li>
                         <li><em>Section 8.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.4">4.1.3</a></li>
-                        <li><em>Section 9.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.6">7.3</a>, <a href="#rfc.xref.Part2.7">B</a></li>
+                        <li><em>Section 8.2.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.5">4.3</a></li>
+                        <li><em>Section 9.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.7">7.3</a>, <a href="#rfc.xref.Part2.8">B</a></li>
                      </ul>
                   </li>
@@ -2268 +2235 @@
                   </li>
                   <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">9.3</a>, <a href="#RFC3864"><b>12.2</b></a></li>
-                  <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">7.2.3</a>, <a href="#rfc.xref.RFC5226.2">7.6.8</a>, <a href="#RFC5226"><b>12.2</b></a><ul>
-                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">7.2.3</a>, <a href="#rfc.xref.RFC5226.2">7.6.8</a></li>
+                  <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">7.2.3</a>, <a href="#rfc.xref.RFC5226.2">7.5.8</a>, <a href="#RFC5226"><b>12.2</b></a><ul>
+                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">7.2.3</a>, <a href="#rfc.xref.RFC5226.2">7.5.8</a></li>
                      </ul>
                   </li>
@@ -2299 +2266 @@
                      </ul>
                   </li>
-                  <li>Vary header field&nbsp;&nbsp;<a href="#rfc.xref.header.vary.1">4.3</a>, <a href="#rfc.iref.v.3"><b>7.5</b></a>, <a href="#rfc.xref.header.vary.2">9.3</a></li>
                </ul>
             </li>
@@ -2305 +2271 @@
                   <li>Warn Codes&nbsp;&nbsp;
                      <ul>
-                        <li>110 Response is Stale&nbsp;&nbsp;<a href="#rfc.iref.w.2"><b>7.6.1</b></a>, <a href="#rfc.xref.warn.110.1">9.2</a></li>
-                        <li>111 Revalidation Failed&nbsp;&nbsp;<a href="#rfc.iref.w.3"><b>7.6.2</b></a>, <a href="#rfc.xref.warn.111.1">9.2</a></li>
-                        <li>112 Disconnected Operation&nbsp;&nbsp;<a href="#rfc.iref.w.4"><b>7.6.3</b></a>, <a href="#rfc.xref.warn.112.1">9.2</a></li>
-                        <li>113 Heuristic Expiration&nbsp;&nbsp;<a href="#rfc.iref.w.5"><b>7.6.4</b></a>, <a href="#rfc.xref.warn.113.1">9.2</a></li>
-                        <li>199 Miscellaneous Warning&nbsp;&nbsp;<a href="#rfc.iref.w.6"><b>7.6.5</b></a>, <a href="#rfc.xref.warn.199.1">9.2</a></li>
-                        <li>214 Transformation Applied&nbsp;&nbsp;<a href="#rfc.iref.w.7"><b>7.6.6</b></a>, <a href="#rfc.xref.warn.214.1">9.2</a></li>
-                        <li>299 Miscellaneous Persistent Warning&nbsp;&nbsp;<a href="#rfc.iref.w.8"><b>7.6.7</b></a>, <a href="#rfc.xref.warn.299.1">9.2</a></li>
-                     </ul>
-                  </li>
-                  <li>Warning header field&nbsp;&nbsp;<a href="#rfc.xref.header.warning.1">4.1.4</a>, <a href="#rfc.xref.header.warning.2">4.2.1</a>, <a href="#rfc.xref.header.warning.3">4.4</a>, <a href="#rfc.xref.header.warning.4">5</a>, <a href="#rfc.iref.w.1"><b>7.6</b></a>, <a href="#rfc.xref.header.warning.5">9.3</a>, <a href="#rfc.xref.header.warning.6">A</a></li>
+                        <li>110 Response is Stale&nbsp;&nbsp;<a href="#rfc.iref.w.2"><b>7.5.1</b></a>, <a href="#rfc.xref.warn.110.1">9.2</a></li>
+                        <li>111 Revalidation Failed&nbsp;&nbsp;<a href="#rfc.iref.w.3"><b>7.5.2</b></a>, <a href="#rfc.xref.warn.111.1">9.2</a></li>
+                        <li>112 Disconnected Operation&nbsp;&nbsp;<a href="#rfc.iref.w.4"><b>7.5.3</b></a>, <a href="#rfc.xref.warn.112.1">9.2</a></li>
+                        <li>113 Heuristic Expiration&nbsp;&nbsp;<a href="#rfc.iref.w.5"><b>7.5.4</b></a>, <a href="#rfc.xref.warn.113.1">9.2</a></li>
+                        <li>199 Miscellaneous Warning&nbsp;&nbsp;<a href="#rfc.iref.w.6"><b>7.5.5</b></a>, <a href="#rfc.xref.warn.199.1">9.2</a></li>
+                        <li>214 Transformation Applied&nbsp;&nbsp;<a href="#rfc.iref.w.7"><b>7.5.6</b></a>, <a href="#rfc.xref.warn.214.1">9.2</a></li>
+                        <li>299 Miscellaneous Persistent Warning&nbsp;&nbsp;<a href="#rfc.iref.w.8"><b>7.5.7</b></a>, <a href="#rfc.xref.warn.299.1">9.2</a></li>
+                     </ul>
+                  </li>
+                  <li>Warning header field&nbsp;&nbsp;<a href="#rfc.xref.header.warning.1">4.1.4</a>, <a href="#rfc.xref.header.warning.2">4.2.1</a>, <a href="#rfc.xref.header.warning.3">4.4</a>, <a href="#rfc.xref.header.warning.4">5</a>, <a href="#rfc.iref.w.1"><b>7.5</b></a>, <a href="#rfc.xref.header.warning.5">9.3</a>, <a href="#rfc.xref.header.warning.6">A</a></li>
                </ul>
             </li>

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

@@ -33 +33 @@
   <!ENTITY header-connection           "<xref target='Part1' x:rel='#header.connection' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-date                 "<xref target='Part2' x:rel='#header.date' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
+  <!ENTITY header-last-modified        "<xref target='Part4' x:rel='#header.last-modified' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
+  <!ENTITY header-vary                 "<xref target='Part2' x:rel='#header.vary' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-via                  "<xref target='Part1' x:rel='#header.via' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
-  <!ENTITY header-last-modified        "<xref target='Part4' x:rel='#header.last-modified' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY header-fields               "<xref target='Part1' x:rel='#header.fields' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
   <!ENTITY safe-methods                "<xref target='Part2' x:rel='#safe.methods' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
@@ -977 +978 @@
 <t>
    When a cache receives a request that can be satisfied by a stored response
-   that has a <x:ref>Vary</x:ref> header field (<xref target="header.vary"/>),
+   that has a <x:ref>Vary</x:ref> header field (&header-vary;),
    it &MUST-NOT; use that response unless all of the selecting header fields
    nominated by the Vary header field match in both the original request
@@ -1767 +1768 @@
    </t>
 </x:note>
-</section>
-
-<section anchor="header.vary" title="Vary">
-   <iref item="Vary header field" primary="true" x:for-anchor="" />
-   <iref item="Header Fields" primary="true" subitem="Vary" x:for-anchor="" />
-   <x:anchor-alias value="Vary"/>
-<t>
-   The "Vary" header field conveys the set of header fields
-   that were used to select the representation.
-</t>
-<t>
-   Caches use this information, in part, to determine whether a stored
-   response can be used to satisfy a given request; see <xref
-   target="caching.negotiated.responses" />.
-</t>
-<t>
-   In uncacheable or stale responses, the Vary field value advises the user
-   agent about the criteria that were used to select the representation.
-</t>
-<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Vary"/>
-  <x:ref>Vary</x:ref> = "*" / 1#<x:ref>field-name</x:ref>
-</artwork></figure>
-<t>
-   The set of header fields named by the Vary field value is known as the
-   selecting header fields.
-</t>
-<t>
-   A server &SHOULD; include a Vary header field with any cacheable response
-   that is subject to proactive negotiation. Doing so allows a cache to
-   properly interpret future requests on that resource and informs the user
-   agent about the presence of negotiation on that resource. A server &MAY;
-   include a Vary header field with a non-cacheable response that is subject
-   to proactive negotiation, since this might provide the user agent with
-   useful information about the dimensions over which the response varies at
-   the time of the response.
-</t>
-<t>
-   A Vary field value of "*" signals that unspecified parameters not limited
-   to the header fields (e.g., the network address of the client), play a
-   role in the selection of the response representation; therefore, a cache
-   cannot determine whether this response is appropriate. A proxy &MUST-NOT;
-   generate the "*" value.
-</t>
-<t>
-   The field-names given are not limited to the set of standard header
-   fields defined by this specification. Field names are case-insensitive.
-</t>
 </section>
 
@@ -2191 +2145 @@
       <xref target="header.pragma"/>
    </c>
-   <c>Vary</c>
-   <c>http</c>
-   <c>standard</c>
-   <c>
-      <xref target="header.vary"/>
-   </c>
    <c>Warning</c>
    <c>http</c>
@@ -2293 +2241 @@
       <x:defines>Date</x:defines>
       <x:defines>Location</x:defines>
+      <x:defines>Vary</x:defines>
     </x:source>
   </reference>
@@ -2595 +2544 @@
 <x:ref>Expires</x:ref> = HTTP-date
 
-<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 6.1&gt;
+<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 9.1&gt;
 
 <x:ref>OWS</x:ref> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
@@ -2601 +2550 @@
 <x:ref>Pragma</x:ref> = *( "," OWS ) pragma-directive *( OWS "," [ OWS
  pragma-directive ] )
-
-<x:ref>Vary</x:ref> = "*" / ( *( "," OWS ) field-name *( OWS "," [ OWS field-name ]
- ) )
 
 <x:ref>Warning</x:ref> = *( "," OWS ) warning-value *( OWS "," [ OWS warning-value ]
@@ -2634 +2580 @@
 </artwork>
 </figure>
-</section>
+<figure><preamble>ABNF diagnostics:</preamble><artwork type="inline">
+; field-name defined but not used
+</artwork></figure></section>
 <?ENDINC p6-cache.abnf-appendix ?>