Re: MTUs on different paths

Steve Deering <> Tue, 12 December 1989 04:40 UTC

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Date: 11 Dec 1989 20:33-PST
From: Steve Deering <>
Subject: Re: MTUs on different paths
To: Craig Partridge <craig@NNSC.NSF.NET>
Cc: mtudwg
Message-Id: <89/12/11>
In-Reply-To: Craig Partridge's message of Mon, 11 Dec 89 084901 -0500

me:	There is, however, a problem with the RFC-1063 approach of allowing
	the Reply MTU to be piggybacked on any returning datagram -- the
	association between the MTU and its corresponding TOS or other
	route-influencing options may be lost.

Craig:	Well, this is one of the two approaches.
	The other approach has TCP initiating the options and TCP, could
	conceivably, retrieve the option and direct IP as to the TOS being

Yes, that's the second of my "three reasonable ways to return MTU