Re: [quicwg/base-drafts] Requirement of PMTU > 1280 (#1014)

Patrick McManus <notifications@github.com> Wed, 13 December 2017 15:27 UTC

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Date: Wed, 13 Dec 2017 15:27:10 +0000
From: Patrick McManus <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Requirement of PMTU > 1280 (#1014)
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by justification I don't know if you just mean "a good reason" or "text describing the good reason". I think only the former is required in most cases.

anyhow - I recall a few reasons
1] we intentionally restrict ourselves to v6 capable networks as a reasonable cost of 2017 internet admission
2] mtu across the internet is therefore practically 1280-1500 for many cases
3] pmtud is hard and error prone. If you'd like to opt-out of that trouble, 1280 gets you most of the way to pmtu in practice... while 576 doesn't have that property.
4] Having a substantial minimum made the padded-initial possible and easy

I don't recall it being any deeper than that..  but it seems better than no minimum

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