Re: [quicwg/base-drafts] Add note that middleboxes might change datagram boundaries (#3337)

Eric Kinnear <> Fri, 17 January 2020 06:26 UTC

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Date: Thu, 16 Jan 2020 22:26:07 -0800
From: Eric Kinnear <>
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Subject: Re: [quicwg/base-drafts] Add note that middleboxes might change datagram boundaries (#3337)
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erickinnear commented on this pull request.

> @@ -3515,6 +3515,10 @@ A server MAY send a CONNECTION_CLOSE frame with error code PROTOCOL_VIOLATION in
 response to an Initial packet it receives from a client if the UDP datagram is
 smaller than 1200 bytes. It MUST NOT send any other frame type in response, or
 otherwise behave as if any part of the offending packet was processed as valid.
+Note that a middlebox might modify datagram boundaries when multiple QUIC
+packets have been coalesced into a single UDP datagram, causing the handshake to
+fail. This is considered a failure of the path to support datagrams of the size

I tend to agree with both the sentence, as well as your statements. :) 
Really what I'm looking for is "this is a failure on the part of the network and something we've decided to live with and if someone on the path does this, it's their fault" -- better wording welcome!

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