Re: [quicwg/base-drafts] Asymmetry in the handling of SETTINGS frame (#1846)

Lucas Pardue <notifications@github.com> Tue, 09 October 2018 19:31 UTC

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Subject: Re: [quicwg/base-drafts] Asymmetry in the handling of SETTINGS frame (#1846)
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> @LPardue, the defaults apply if the SETTINGS frame arrives and the value is not specified. There simply isn't a value until the SETTINGS frame arrives.

We did move the QPACK-specific settings over in a previous issue/PR; that setting is not quite QPACK-specific. The precise meaning is poorly defined in HTTP/2, and perhaps we should open an issue to clarify: Is it the maximum length of a HEADERS frame, or the maximum length of the decoded headers?

ACK. I've gotten myself confused with this setting and QPACK-specific ones. Sorry!

I think it would be helpful to redefine what this settings means explicitly, or link to the HTTP/2 section if we are carrying that over. 

Back on the true topic of this ticket, I agree with Mike that we need to block on SETTINGS to know exactly what HTTP-level connection characteristics are being 'negotiated'. For example, my candidate [unbound server push extension](https://datatracker.ietf.org/doc/draft-pardue-quic-http-unbound-server-push) would allow a server to start sending PUSH_PROMISE frames on server-initiated unidirectional streams, something that would normally not be allowed in HTTP/QUIC. How would a non-blocking client handle such a case?

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