Re: [hybi] [Technical Errata Reported] RFC7692 (4982)

Moonchild <> Tue, 28 March 2017 20:21 UTC

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To: Takeshi Yoshino <>, RFC Errata System <>
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Cc: Ben Campbell <>,,, Salvatore Loreto <>, Gabriel Montenegro <>, "" <>
From: Moonchild <>
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Date: Tue, 28 Mar 2017 22:20:07 +0200
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Subject: Re: [hybi] [Technical Errata Reported] RFC7692 (4982)
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On 28/03/2017 14:57, Takeshi Yoshino wrote:
> For consistency with other paragraphs, we could also rewrite the
> paragraphs as follows.
> A server MAY ... response _as a hint_ even if ...
> A client MUST support the "server_no_context_takeover" extension
> parameter in an extension negotiation response regardless of whether or
> not the client may include the "server_no_context_takeover" extension
> parameter in an extension negotiation offer.

I think you have to be careful here that you're not going to imply that
a client must support the parameter in its implementation, but merely
that the parameter as part of a response must be *accepted* (but may be
ignored if no implementation is being provided to back this parameter)
as part of a valid configuration. That is why I suggested my initial
errata wording as I did in the corrected text.

I also agree that the exact same rationale applies to
"server_max_window_bits" since that can also be sent unsolicited by the
server to a client, even if the client may not support that functionality.