Re: Location Proposals

If there is a real possibility that caches would fail to update, or at
least invalidate (which would be almost as good), items in their
caches as a result of receiving Location headers, then I am forced to
agree with you -- certain kinds of pages just have to be completely
uncacheable.  :(.  

At this point, using Location would just be introducing a very slight
bandwidth saving -- so slight as to hardly be worth the trouble, I
think.  If certain dynamic pages must always be pre-expired (not
servable from a cache), then Location is unnecessary to prevent
"doppelgangers" -- out of date duplicates in a cache under different
URIs.  This was what I imagined as its main use in the context of
caching.  Oh well.

The case of the cache that goes down for a while, and comes up holding
now-invalidated copies of things without knowing it, seems to apply
more generally than to just this case, however.

--Shel