If-Modified-Since enhancement

Ari Luotonen (luotonen@ptsun00.cern.ch)
Sun, 20 Mar 1994 22:03:19 --100

We have currently spec'd the conditional GET to work as follows:

GET /what/ever HTTP/1.0
If-Modified-Since: Wednesday, 16-Mar-94 10:57:20 GMT

If /what/ever has been modified (or server doesn't support
If-Modified-Since: header) the doc is sent back normally.
However, if the doc is unchanged, server replies:

HTTP/1.0 304 Not modified

I suggest that the rest of this response would be as if the client
(proxy) had sent a HEAD request -- this way the server can upload
a new expiry date (and other meta info) to proxy:

HTTP/1.0 304 Not modified
Expires: Sunday, 27-Mar-94 12:00:00 GMT
...

-- Cheers, Ari --