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From: Mills@UDEL.EDU
Newsgroups: comp.protocols.tcp-ip
Subject: Re:  Submission for mod-protocols-tcp-ip
Message-ID: <8704231336.a020393@Huey.UDEL.EDU>
Date: Thu, 23-Apr-87 13:36:16 EDT
Article-I.D.: Huey.8704231336.a020393
Posted: Thu Apr 23 13:36:16 1987
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Howard,

If you don't mind unslinging the big guns, see RFC-958 for techniques to
accurately measure roundtrip delay and clock offset, which is equivalent
to one-way delays. Improve sample estimates using a median filter as
described in RFC-956. Improve statistical estimates by including all
TCP segments, not just those allowing a single roundtrip estimate at
a time. This last requires state variables for all outstanding segments
that have not been ACKed.

This topic has come up about once a year since early this decade. The
last volley on this list (before Van Jacobson kicked off the current
game) was between John Nagle and myself. My conclusion after all this
is that the implementor should think more like a statistician and less
like a protocol engineer.

Dave