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Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!inuxc!pur-ee!uiucdcs!smu!pedz
From: pedz@smu.UUCP
Newsgroups: net.mail
Subject: Re: definitions for LOCAL, DEMAND, DAILY
Message-ID: <14000006@smu.UUCP>
Date: Thu, 24-Jan-85 17:55:00 EST
Article-I.D.: smu.14000006
Posted: Thu Jan 24 17:55:00 1985
Date-Received: Sun, 27-Jan-85 04:42:31 EST
References: <700@cbosgd.UUCP>
Lines: 22
Nf-ID: #R:cbosgd:-70000:smu:14000006:000:982
Nf-From: smu!pedz    Jan 24 16:55:00 1985

The first problem is that pathalias assumes the cost of a link
is the same in both directions (at least I think it does).  This
is often not correct since site A may call site B on demand but
site B calls site A only once a day.  Thus if no requests are
made at A to go to B, a request going from B to A will have a
link of once a day.  I realize that when uucp calles up,
messages are passed both ways.  However, the weights are
basically describing the frequency of the calls.

The second point is that pathalias and its algorithms are only
the first attempt at solving the problem.  Therefor the site
description should contain as much as possible (within reason of
course) so that future programs may take advantage of it.  Thus
the "double" link problem (of having a site call another site on
demand and once per day) should be solved by putting the
information into the site's description and pathalias can ignore
it if it wants to.

Perry
convex!smu!pedz
pedz@smu    (csnet)