RE: Demographics

Paul Leach writes:
	...
 > If fact, "Referer" makes it very hard for a cache to be semantically
 > transparent: if a cache was trying to be semantically transparent, the
 > presence of "Referer" on a GET request should cause a cache to do a
 > conditional GET on the Request-URI.  The only way to avoid this would be
 > to remember each different value of Referer: had been seen and to report
 > hit counts on each of them (somehow). Not only is this more complex than
 > using cached 302s, it also would result in exactly as many remembered
 > Referers as cached 302s in your proposal.
 > > 

Not that I'm recommending this per se, but if a server cared about
this, it could use the Vary header to indicate the result
varies on the Referer request-header, causing any caches to treat the
results independently. 

Of course this would mean a lot more bookkeeping entries in caches, but
implementation-wise, if caches could have unique entries for resources that
were logically different but physically identical (using a digest hash
or something), this wouldn't be that much uglier than some
special case method of keeping track specifically by Referer.

--Shel

Received on Wednesday, 10 July 1996 12:46:22 UTC