Re: HTTP-NG: status report

Simon E Spero (ses@tipper.oit.unc.edu)
Tue, 22 Nov 94 07:07:48 -0500


>>>>> "Brian" == Brian Behlendorf <brian@wired.com> writes:

Brian> Looked great!

Brian> The act of fetching inlined images could be made faster if
Brian> the server were able to tell the client directly in its
Brian> response headers "I think you'll want to get these items
Brian> next" - that way the client doesn't have to parse the
Brian> document as it's coming down the pipe looking for inlined
Brian> images. I.e., in HTTP/1.0 terms (since I haven't seen the
Brian> HTTP-NG terms)

That's in there - there was some discussion on how best to handle
this; there are three possiblities that need to be evaluated; only the first
is definitely in there.

Fields in the MetaInformation record:

inlined-objects SEQUENCE OF URI OPTIONAL,
linked-to-objects SEQUENCE OF URI OPTIONAL

This allows the server to attach two lists of URIs to the metainformatin -
one for inline objects, the other for links.

Flag in the GetRequest:

send-inlined-objects BOOLEAN DEFAULT FALSE

This tells the server to automatically send all inlined-objects. This saves
a round trip, and helps to keep the window full, but needs careful tuning to
work well with client caches (the client can cancel individual streams, but
because TCP is reliable, there may already be a windows worth of data in the
pipeline.)

Options in the initialise request.

send-unsolicited-objects BOOLEAN DEFAULT FALSE

This allows the server to send objects for which it hasn't recieved a direct
request; this allows the server to send images automatically, but also allows
commonly followed links to be pre-loaded. Unsolicited requests can be cancelled
or if accepted, acknowledged (this is needed to the prediction algorithms).

Simon