Re: [quicwg/base-drafts] max_datagram_size being a variable means other constants become variables (#3205)

Gorry Fairhurst <notifications@github.com> Tue, 19 November 2019 02:32 UTC

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Date: Mon, 18 Nov 2019 18:32:17 -0800
From: Gorry Fairhurst <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] max_datagram_size being a variable means other constants become variables (#3205)
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I have thoughts... I suggest the currently definition wrt max_datagram_size raises new safety issues. I am not sure a minimum of 10 * max_datagram_size, where max datagram, is say 9KB or 16KB, is actually something that is safe. From what I recall, the MSS term in IW for TCP related to sub 1500B MSS, and the need to constrain, not safe to expand. I suggest we define this in terms of the base size of 1280B. 

There is also an evil pathology in IPv4, where this can result in a router on path fragmenting larger packets to result in intense bursts of packets. 

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