RE: Header Compression: Reference set choice

Couldn't this also be closely approached simply by allowing a range of Indexed Headers along with a HEADERS flag to clear the reference set before processing the frame?

This implies that the interesting headers need to be contiguous in the table.  That's not necessarily the case (in my implementations so far, anyway), and would require some form of insert mechanism to make it really convenient for a compressor to leverage it, as you mention in 6.4.  If Range were an operation, multiple disjoint ranges could be quickly added, helping to alleviate that need.

If we're going to introduce multiple reference sets, I'd be more inclined to the version that appeared in Roberto's original proposals of being able to select from a bounded number of reference sets for each header set.  Each reference set begins empty, gets filled the first time it's used, and remains thereafter.

-----Original Message-----
From: RUELLAN Herve [mailto:Herve.Ruellan@crf.canon.fr] 
Sent: Tuesday, July 30, 2013 7:53 AM
To: ietf-http-wg@w3.org
Subject: Header Compression: Reference set choice

We did some work on the diff part of the header compression format, and are proposing enhancements to the choice of the reference set used to encode a new header set (i.e. the starting point for the diff). This is detailed in a draft:
http://tools.ietf.org/html/draft-ruellan-reference-set-definition-00

This is still work in progress, as we didn't have time to do enough measurement, in particular on long lasting connections.

Comments are welcome,

Hervé.

Received on Tuesday, 30 July 2013 23:23:58 UTC