Re: Alt-SvcB

On Wed, Oct 26, 2022, at 10:21, David Schinazi wrote:
> h3 hints are a great example of something that needs to be added to 
> Alt-Svc. 

So I think that we're fixated a little much on a specific interpretation of "obsoletes" here.

TLS 1.3 obsoleted TLS 1.2.  That has not stopped the TLS community from publishing a number of RFCs that specifically extend TLS 1.2.

In TLS 1.2, just like Alt-Svc, we have clear problems, but an ongoing deployment need.  For TLS, it is primarily deployment costs (1.3 is a relatively big lift), with a sprinkling of other attachments. For Alt-Svc, it is the signal of HTTP/3 support where HTTPS doesn't work.  That's more than just an OS problem.  It's also tied up with deployment of networking gear in some cases, so we'll probably be stuck with it as long as the desire to use HTTP/3 in those affected cases is significant.

We're not proposing that we *deprecate* Alt-Svc.  This isn't RFC 8996 for TLS 1.1/1.0 where the use of the protocol is actively discouraged.  RFC 8996 came some time after TLS 1.2/RFC 5246.  Though perhaps folks like Lucas might want that deprecation to happen sooner rather than later, we recognize that Alt-Svc is needed.  That is, until the problems Alt-Svc causes starts to look bad relative to the diminishing number of clients that need it to get HTTP/3.

As others have noted, we'll probably need the HTTP/3 signal for some time.  But we might be able to narrow that over time.

We're not taking Alt-Svc away.  We're merely saying that it is not our preferred solution any more.

Received on Wednesday, 26 October 2022 00:41:49 UTC