From newshub.ccs.yorku.ca!ists!helios.physics.utoronto.ca!news-server.csri.toronto.edu!rpi!think.com!mintaka.lcs.mit.edu!spdcc!dirtydog.ima.isc.com!ispd-newsserver!psinntp!scylla!daryl Thu Feb 20 15:21:03 EST 1992
Article 3762 of comp.ai.philosophy:
Newsgroups: comp.ai.philosophy
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>From: daryl@oracorp.com
Subject: Message to Pontus Gagge
Message-ID: <1992Feb14.190707.14233@oracorp.com>
Organization: ORA Corporation
Date: Fri, 14 Feb 1992 19:07:07 GMT

I apologize for using this forum for a personal message, but I don't
know how to reach Mr. Gagge by e-mail

I received your e-mail message, but when I attempted to reply, the message
"bounced". Here is my reply:

The most famous books on the subject of process algebras have been
Robin Milner's Calculus of Communicating Systems (CCS) and Tony
Hoare's Communicating Sequential Processes (CSP). There has also been
a lot of work done in Holland, but I don't know of any books on the
subject, only technical reports.

Process algebra doesn't replace the theory of finite state machines,
but only adds to it. The main issues for process algebra above and
beyond finite automaton theory are:

   1. When should two different descriptions of a machines be
      considered to be describing the same machine?

   2. How can one combine small machines to get larger machines?

Hoare and Milner come up with slightly different answers for the two
questions, but neither answer is the same as for classical finite
automaton theory, which doesn't concern itself with combining
machines, and only gives a very simplistic notion of equivalence of
machines: two machines are equivalent if they recognize the same
language.

Daryl McCullough
ORA Corp.
Ithaca, NY

P.S. Where is Link|Ping?



