Changeset 766 for draft-ietf-httpbis/latest/p6-cache.xml

Timestamp:

03/03/10 09:19:25 (12 years ago)

Author:

julian.reschke@…

Message:

Simplify discussion of history lists (see #197)

File:

• draft-ietf-httpbis/latest/p6-cache.xml (modified) (2 diffs)

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

@@ -1545 +1545 @@
 </t>
 <t>
-  History mechanisms and caches are different. In particular history mechanisms
-  &SHOULD-NOT; try to show a correct view of the current state of a resource. Rather, a
-  history mechanism is meant to show exactly what the user saw at the time when the resource
-  was retrieved.
-</t>
-<t>
-  By default, an expiration time does not apply to history mechanisms. If the entity is still
-  in storage, a history mechanism &SHOULD; display it even if the entity has expired,
-  unless the user has specifically configured the agent to refresh expired history documents.
-</t>
-<t>
-  This is not to be construed to prohibit the history mechanism from telling the user that a
-  view might be stale.
-</t>
-<x:note>
+  The freshness model (<xref target="expiration.model"/>) does not necessarily apply to history mechanisms. I.e., 
+  a history mechanism can display a previous representation even if it has expired.
+</t>
   <t>
-    <x:h>Note:</x:h> If history list mechanisms unnecessarily prevent users from viewing
-    stale resources, this will tend to force service authors to avoid using HTTP expiration
-    controls and cache controls when they would otherwise like to. Service authors may
-    consider it important that users not be presented with error messages or warning
-    messages when they use navigation controls (such as BACK) to view previously fetched
-    resources. Even though sometimes such resources ought not be cached, or ought to expire
-    quickly, user interface considerations may force service authors to resort to other
-    means of preventing caching (e.g., "once-only" URLs) in order not to suffer the effects
-    of improperly functioning history mechanisms.
+  This does not prohibit the history mechanism from telling the user that a
+  view might be stale, or from honoring cache directives (e.g., Cache-Control: no-store).
   </t>
-</x:note>
 </section>
 
@@ -2344 +2324 @@
 <section anchor="changes.since.08" title="Since draft-ietf-httpbis-p6-cache-08">
 <t>
+  Closed issues:
+  <list style="symbols"> 
+    <t>
+      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/197" />:
+      "Effect of CC directives on history lists"
+    </t>
+  </list>
+</t>
+<t>
   Affected issues:
   <list style="symbols">