Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ANDREW.CMU.EDU!ep0y+
From: ep0y+@ANDREW.CMU.EDU ("Erik D. Perkins")
Newsgroups: comp.protocols.tcp-ip
Subject: RFC 1063 question
Message-ID: <kYpa2LK00UoJME6UNL@andrew.cmu.edu>
Date: 2 Aug 89 02:46:47 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 25


I am implementing the MTU discovery IP options for our gateway software.
 My question is:  should the IP MTU Request option be copied into
fragments upon fragmentation of the original datagram?  RFC 1063 doesn't
specify.  It is "obvious" that the reply option shouldn't be copied,
because it isn't changed.  Can anyone suggest a compelling reason to
copy the request option?

The individual fragments could conceivably travel over different routes,
so MINMTU values may differ.  Would this information be useful when the
original datagram is reassembled?  The general feeling around here is
that the answer is no.

There doesn't seem to be any real benefit to justify the extra
gateway/host overhead.  Any other thoughts???

(BTW, what is IP option 10?  Strict Source Routing is option 9 and MTU
Request is option 11.  Just wondering...)


thanks in advance,

erik perkins
network development
carnegie mellon