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From: jon@CS.UCL.AC.UK (Jon Crowcroft)
Newsgroups: comp.protocols.tcp-ip
Subject: IP datagram sizes
Message-ID: <8706011445.AA14258@ucbvax.Berkeley.EDU>
Date: Mon, 1-Jun-87 10:47:22 EDT
Article-I.D.: ucbvax.8706011445.AA14258
Posted: Mon Jun  1 10:47:22 1987
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Of course, if you use X.25 you don't have this problem :-). The
switches can use level 2 to support fragment sizes properly
over each hop, and level 3 to get end to end packet sizes
efficient, and a well known transport protocol over that...

Then all you need is to work out how to get CCITT to accept
giant window size and packet size options to make it work well
over a big network.

The strain of hop by hop versus end to end arguments starts to
show when you try and use an underengineered mil-spec net for
heavy duty service.

What Vint says sounds good to me - figure out how to get hop by
hop information back to the end to end protocols so they can be
taught how to behave properly. Real problem here is for short
lived protocol entities - eg query systems running in PCs - who
dont get a chance to used previously cached info...

jon