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From: braden@ISI.EDU (Bob Braden)
Newsgroups: mod.protocols.tcp-ip
Subject: Re: Setting Initial Round-trip time
Message-ID: <8610311716.AA00139@braden.isi.edu>
Date: Fri, 31-Oct-86 12:16:55 EST
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Posted: Fri Oct 31 12:16:55 1986
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	The problem with the cache is that a) you don't know if the values
	correspond to the routes your traffic is/will take. b) you may not
	have enough traffic to enough destinations to maintain statistically
	valid (fresh) delay information. It may be possible that things will
	be static enough that cache will actually work well most of the time,
	but if the internet exhibits significant statistical variation in
	delay/throughput, the cache may be not only misleading but downright
	harmful.
	
Vint, 

Everything you say is true, but I fail to see how bad cache information
will be more harmful than no information at all.

Bob Braden