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From: zweig@p.cs.uiuc.edu
Newsgroups: comp.protocols.tcp-ip
Subject: Re: TCP Port question
Message-ID: <93400022@p.cs.uiuc.edu>
Date: 25 May 89 19:09:00 GMT
References: <364@toro.UUCP>
Lines: 48
Nf-ID: #R:toro.UUCP:364:p.cs.uiuc.edu:93400022:000:1977
Nf-From: p.cs.uiuc.edu!zweig    May 25 14:09:00 1989


::Written 11:17 pm  May 23, 1989 by toddpw@tybalt.caltech.edu:
::
::In article <364@toro.UUCP> nick@toro.UUCP (Nicholas Jacobs) writes:
::>In RFC 1010, there is a list of officially defined ports used by TCP
::>(and by UDP wherever possible). I am writing a server process which
::>hangs on a "well-known" port which can supply both the official ports
::>(given a port name or number) and to which locally defined ports can be
::>added to dynamically (thus programs can ask this process to generate
::>new port numbers).
::>
::>I have 2 questions:
::>	1) Is this service already defined (and thus I should simply
::>	   mimic its behavior)?
::>	2) Failing that, is there a port that is recommended for this
::>	   service (I am planning on using IPPORT_RESERVED+1)?
::
::1) yes, it's in RFC 1078 (TCPMUX).
::2) i'm not sure, see 1078.
::
::one thought on 1078 as I remember it: using TCP for a simple transaction like
::the port server is overkill when using UDP would require a simple two packet
::exchange process.
::
::Has anyone actually implemented something like this or do we have to wait 
::until BSD does it?
::
::Todd Whitesel
::toddpw @ romeo.caltech.edu
::toddpw @ caltech.bitnet
::toddpw @ CITDEIMO

This brings up that problem that RFC1078 in almost impossible to understand
unless you already know what it does. It says "then the service begins" --
but is it still on Port 1? Or does the service implicitly set up a different
port number? Does this mean only one thing can be happening on Port 1 at any
time? Sounds like a shabby multiplexer if it only multiplexes one thing at a
time....


-Johnny Zweig
 University of Illinois at Urbana-Champaign
 Department of Computer Science
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