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Re: stateless reset in response to packet that is 43 bytes

Martin Thomson <mt@lowentropy.net> Mon, 01 June 2020 01:34 UTC

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Date: Mon, 01 Jun 2020 11:33:49 +1000
From: Martin Thomson <mt@lowentropy.net>
To: quic@ietf.org
Subject: Re: stateless reset in response to packet that is 43 bytes
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The packet with a short header that has the lowest length, but a maximum-length connection ID is 1 (type) + 20 (destination connection ID) + 4 (packet number + data) + 16 (aead expansion) = 41 bytes.

Hmm, maybe this should be 42 instead of 43.  I always get this bit wrong though.

On Mon, Jun 1, 2020, at 02:55, Jiuhai Zhang wrote:
> https://tools.ietf.org/html/draft-ietf-quic-transport-27#section-10.4
> An endpoint that sends a stateless reset in response to
>    packet that is 43 bytes or less in length SHOULD send a stateless
>    reset that is one byte shorter than the packet it responds to.
> Could someone explain why it is 43 bytes? thks

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