- From: Benjamin Kaduk <bkaduk@akamai.com>
- Date: Sat, 1 Sep 2018 23:05:13 -0500
- To: Felix Handte <felixh@fb.com>
- Cc: Mark Nottingham <mnot@mnot.net>, Jyrki Alakuijala <jyrki@google.com>, Charles McCathie-Neville <chaals@yandex-team.ru>, Evgenii Kliuchnikov <eustas@google.com>, Vlad Krasnov <vlad@cloudflare.com>, Nick Terrell <terrelln@fb.com>, Yann Collet <cyan@fb.com>, HTTP Working Group <ietf-http-wg@w3.org>
On Fri, Aug 24, 2018 at 10:24:23AM +0000, Felix Handte wrote: > Jyrki, > > Glad to hear it! We're excited too! > > We look forward to playing with Brotli's new capabilities when they're available. > > Yes, Zstd can accept unformatted buffers as dictionaries, which it uses as you describe. Additionally though, Zstd describes a format for structured dictionaries[1], which includes metadata in addition to an LZ77 prefix. One topic that came up during IESG review of draft-kucherawy-dispatch-zstd was whether/when third-party or standard dictionaries would become available and how dictionary IDs would be assigned for those cases (since at present, IIUC, the dictionary IDs would need to be pre-negotiated between the two parties). No IANA registry was created at that time, but with a 4-byte dictionary identifier space to work with, it seems like there might be space to create a registry for dictionary IDs (including private use space, of course), and just publishing well-known dictionaries. -Ben > [1] https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#dictionary-format <https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#dictionary-format> > [2] https://tools.ietf.org/html/draft-vandevenne-shared-brotli-format-01#section-9 <https://tools.ietf.org/html/draft-vandevenne-shared-brotli-format-01#section-9> >
Received on Monday, 3 September 2018 07:21:41 UTC