Re: Submitted new I-D: Cache Digests for HTTP/2

[Alex Rousskov <[e-mail]>]

On 01/10/2016 10:11 AM, Alcides Viamontes E wrote:

> Let's then use 200 as a ballpark estimate of the number of
> items in a cache digest and start from there.
...
> Therefore, with a
> digest of size 200, we would be using an upper bound of around 18 kB

Hm.. If 200-URL site is the primary target, then a 1:1 bitmap (200 bits
or 25 bytes) can be used. The origin server can return an HTTP header
indicating the bitmap index of the response so that the client knows
which digest bit to turn on for that cached response.

With just 200 URLs, maintaining a set of unique URL indexes cannot be
very difficult and, with an addition of a "digest version" (4 more
bytes), can be fully automated to accommodate changes in the URL set.

Alex.