- From: James M Snell <jasnell@gmail.com>
- Date: Wed, 27 Mar 2013 17:29:12 -0700
- To: Roberto Peon <grmocg@gmail.com>
- Cc: RUELLAN Herve <Herve.Ruellan@crf.canon.fr>, "agl@google.com" <agl@google.com>, Mark Nottingham <mnot@mnot.net>, "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
On Wed, Mar 27, 2013 at 5:14 PM, Roberto Peon <grmocg@gmail.com> wrote: > I've checked in some changes to delta2 which expands and documents various > options for delta2 in the README.md. > > After running a number of variations of delta2, The following defaults look > good for small buffer sizes: > > delta2=max_entries=256, small_index=1 Oh excellent. I had hit on this as well. To be honest, I'm not sure max_entry > 256 would ever really make much practical sense. - James > > small_index basically says use a uint8 instead of a uint16 for representing > indices, and is the kind of thing that could be messaged somewhere (opcode, > flag, whatever). > > The best headerdiff option which I believe is safe against CRIME in the > future is: > headerdiff=delta_type=false,huffman > > I removed prefix matching from delta some months ago (~6 I think?) after > cogitating on it for a while and then speaking with security folks.. I just > couldn't come up with a way I could prove was safe, unlike the > atom-matching, which one can prove is no worse than a brute-force attack. > > I've appended runs with these values@4k buffer size for delta2 and > headerdiff below. > -=R > > > > * TOTAL: 5949 req messages > > size time | ratio min max std > > http1 3,460,925 0.13 | 1.00 1.00 1.00 0.00 > delta2 (max_byte_size=4096, max_entries=256, small_index=1, hg_adjust=0, > implicit_hg_add=0, refcnt_vals=0) 664,683 4.16 | 0.19 0.02 0.83 > 0.15 > headerdiff > (buffer=4096, delta_type=false, huffman) 759,783 2.03 | 0.22 0.01 > 0.78 0.18 > > * TOTAL: 5948 res messages > > size time | ratio min max std > > http1 2,186,162 0.12 | 1.00 1.00 1.00 0.00 > delta2 (max_byte_size=4096, max_entries=256, small_index=1, hg_adjust=0, > implicit_hg_add=0, refcnt_vals=0) 585,475 5.32 | 0.27 0.02 1.28 > 0.13 > headerdiff > (buffer=4096, delta_type=false, huffman) 543,047 3.29 | 0.25 0.02 > 0.73 0.14 > > >
Received on Thursday, 28 March 2013 00:29:59 UTC