[Ntp] Is the real MTU still 576?

Hal Murray <hmurray@megapathdsl.net> Mon, 15 June 2020 00:52 UTC

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Subject: [Ntp] Is the real MTU still 576?
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There was mention in the Roughtime discussion that the official minimum MTU is 
still 576.

It's easy for a NTP packet using NTS to get over that.  If you drop a few 
packets, the request will have a few cookie placeholders and the response will 
have a few extra cookies.

Is the real MTU still 576?  What fraction of the net will carry Ethernet size 
packets of roughly 1500 bytes?

Or rather, what fraction of the net can't carry 1500 byte packets and/or how 
well do things work there?

Cookies are roughly 100 bytes.  Should we limit requests to 3 cookie 
placeholders?  (maybe 4)


-- 
These are my opinions.  I hate spam.