Re: Alt-SvcB

Hi Martin,

Thanks for writing this up. Overall I think the long-term strategy makes
sense, but I think it's too early to obsolete/deprecate 7838. It's fairly
common for browsers to use getaddrinfo() on some platforms and that does
not provide access to HTTPS RRs. In those cases, 7838 is the only path to
using HTTP/3, so I expect browsers to keep using it for quite some time.
Marking 7838 as obsolete doesn't reflect that reality.

David

On Mon, Oct 24, 2022 at 5:10 PM Martin Thomson <mt@lowentropy.net> wrote:

> Hey everyone,
>
> The Alt-Svc design team has been very busy recently and making some
> progress on working out an alternative alternative services design.
>
> I just posted
> https://martinthomson.github.io/alt-svcb/draft-thomson-httpbis-alt-svcb.html
> as a -00 draft.  This outlines the alternative design that we've been
> exploring in the design team.
>
> The basic idea is split into two procedures:
>
> 1. Use: When an Alt-SvcB field or ALTSVCB frame is encountered, the client
> looks for HTTPS records for the provided name in the DNS and creates a
> connection using what it learns.
> 2. Reuse: When a client that has previously used an alternative service
> connects again, it remembers the HTTPS record that worked.  It performs a
> regular HTTPS record lookup for the server - not using the alternative that
> it learned, but the name from the URI - but it prefers the alternative it
> previously used if that alternative appears in the results.
>
> The draft explains in more detail and goes into some of the implications
> of the design.
>
> This is not done by any imagining.  We have a bunch of open issues at
> https://github.com/martinthomson/alt-svcb/issues that do require some
> amount of input.  But we think that this is a promising approach and would
> appreciate more input.
>
> Cheers,
> Martin
>
>