Re: [quicwg/base-drafts] HTTP/3 settings frames and prioritization (#2772)

Mike Bishop <> Thu, 06 June 2019 23:39 UTC

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From: Mike Bishop <>
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Subject: Re: [quicwg/base-drafts] HTTP/3 settings frames and prioritization (#2772)
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The first is true -- the server SHOULD send its SETTINGS frame immediately.  However, any packet can be delayed, so the client can't count on having seen SETTINGS prior to being able to send a request.  This constrains the use of placeholders, header compression, extensions, etc.

The current design permits the implementation to choose -- block on the SETTINGS frame (which used to be required) or send requests under the (very conservative) default constraints and do better once SETTINGS arrives.  Our decision was to open up this flexibility of design rather than requiring either behavior.

Do you have suggestions on how to make this clearer?

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