Changeset 1400 for draft-ietf-httpbis/latest/p6-cache.xml

Timestamp:

22/08/11 07:53:05 (11 years ago)

Author:

mnot@…

Message:

Clarify one-year limit on Expires; addresses #290

File:

• draft-ietf-httpbis/latest/p6-cache.xml (modified) (3 diffs)

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

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