Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!ames!mailrus!cornell!uw-beaver!blake!oregon!jqj
From: jqj@oregon.uoregon.edu (J Q Johnson)
Newsgroups: comp.sys.proteon
Subject: Re: TCP & UDP over PRONET80
Message-ID: <113@oregon.uoregon.edu>
Date: 15 Dec 88 13:27:34 GMT
References: <3756@jpl-devvax.JPL.NASA.GOV>
Organization: University of Oregon
Lines: 19

In article <3756@jpl-devvax.JPL.NASA.GOV>, mike@jpl-devvax.JPL.NASA.GOV (Mike Tankenson) writes:
> We're in the process of putting together a PRONET80 ring, running TCP/IP.
> The application involves several megabits of blocked telmetry data running
> between a Gould (and perhaps a Sun or Masscomp).  We're trying to determine
> whether TCP or UDP would be more appropriate as the transport protocol.  We
> have lots of experience with TCP/IP over Ethernet, but zilch when it comes
> to Token Ring.

I have no TR experience either, so can't answer the specific questions. 
However, in response to the general questions of UDP vs TCP for high
speed transfer, the current wisdom is "go with TCP, but with the Van
Jacobsen performance enhancements such as header prediction." There is
no reason to believe that TCP should be much if any slower than UDP,
especially since there now exist very carefully tuned high performance
TCP implementations for Unix.  Although Sun presumably did some
performance tuning to their UDP for NFS, it isn't clear that they did
anywhere near as good a job as Van. 

Meanwhile, even if your medium were perfectly reliable you'd still lose
with UDP as soon as you added a gateway.