W3C home > Mailing lists > Public > http-caching-historical@w3.org > February 1996

Re: "Cache-control: no-cache", "Cache-control: private", and , extensibility

From: Jeffrey Mogul <mogul@pa.dec.com>
Date: Tue, 20 Feb 96 11:56:44 PST
Message-Id: <9602201956.AA07124@acetes.pa.dec.com>
To: "David W. Morris" <dwm@shell.portal.com>
Cc: HTTP Caching Subgroup <http-caching@pa.dec.com>
Oh dear, I'm afraid I've confused matters by assuming that we had
shared definition for the term "to store".

I was trying to make a distinction between two things a cache might
do with a data item (response or part thereof):
	(1) return it in response to some request other than the
	one that cause the cache to receive the data in the first place.
	(2) save it in some storage medium (disk, RAM, etc.)

The reason I was making this distinction is that some people
(specifically Dave Morris) had insisted on the ability to specify that
caches NOT do #2 for some resources.  Not that I necessarily think this
is a good thing to put into the protocol, but apparently some customers
insist on this sort of nonsense (not to bias the discussion or
anything :-).

I had thought that Roy was using the word "store" in this more specific
meaning, and apparently he was.  I.e., his clarification today that
"must not be stored unless the user explicitly requests it through a
separate action" means "must not be stored by a cache but the user
may explicitly save the value to a file outside the control of the
application" (or something close to that).  I'm not quite sure if this
applies to history buffers, either.

Roy then managed to confuse me again by objecting to my proposal
for "Cache-control: no-store" because it doesn't solve the
eavesdropping problem, but I think this is an inconsistent position.
Either the protocol spec says nothing about "storing" values, but
confines itself to specifying when they may be "returned" from a
cache ... or the spec DOES talk about when they can be stored, in
which case it seems appropriate to give servers and users some
control over this.

-Jeff
Received on Tuesday, 20 February 1996 20:16:23 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 19:55:57 UTC