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Path: utzoo!linus!philabs!prls!amdimage!amdcad!decwrl!decvax!vortex!lauren
From: lauren@vortex.UUCP (Lauren Weinstein)
Newsgroups: net.mail
Subject: Re: Mail addressing and routing
Message-ID: <734@vortex.UUCP>
Date: Tue, 6-Aug-85 13:22:56 EDT
Article-I.D.: vortex.734
Posted: Tue Aug  6 13:22:56 1985
Date-Received: Sat, 10-Aug-85 20:45:05 EDT
References: <644@adobe.UUCP>
Organization: Vortex Technology, Los Angeles
Lines: 27

One of the problems with state-based schemes (or any system that
doesn't encourage the use of direct or semi-direct hops--that is,
local exceptions to "route to the state handler" routings), is that
it tends to put a tremendous amount of load on the particular site
that is acting as that gateway (usually for free) and encourages
what might be called "sloppiness" in tables.  My own view is 
that local tables should only resort to sending to "gateway" machines
for a geographic area (or a logical area, which makes more sense
the way some regions are set up) when more specific local information
isn't known.

For example, many sites call vortex directly.  If mail is addressed
to vortex.UUCP (for example) they should call directly if possible.  Sites
that have specific enough information to route to vortex would use whatever
information they have, even for multiple hops.  Only if all else
failed would routing be done through the top-level domain and
subdomains (e.g. CA).  If too much reliance is put on "gateway" subdomain
servers, they will swamped.  Also, in many cases routing will be
much slower than more direct routes.  For example, getting to vortex
is generally much faster through a number of East coast machines than the
most common West coast machines--and tables should be aware of that
fact whenever possible.  If all mail to vortex routed through the 
theoretical CA site, rather than using better information when available,
not only would that CA site be footing unnecessary costs but message
turnaround time would be increased as well.

--Lauren--