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Re: Internet Exchanges supporting jumbo frames?


From: Mikael Abrahamsson <swmike () swm pp se>
Date: Thu, 10 Mar 2016 18:16:46 +0100 (CET)

On Thu, 10 Mar 2016, Tassos Chatzithomaoglou wrote:

Mikael Abrahamsson wrote on 10/3/16 18:21:

However, I stand by my earlier statement that we need to include MTU/MRU in ND messages, so that this can be negotiated 
on a LAN where not all devices support large MTU.


Isn't this already supported?
https://tools.ietf.org/html/rfc4861#section-4.6.4

That is in RAs, and pertains to a prefix. Also, if a device can't use the advertised MTU, they will keep lower MTU which might be causing MTU mismatch.

For instance, if I announce 9000 as MTU and a device is bridged via wifi, wifi chips generally only supports around 2300 in MTU, so you'll have MTU mismatch with MTU blackholing within the same L2 network. This is bad.

--
Mikael Abrahamsson    email: swmike () swm pp se


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