Classifying behavior of protocols.

Abstract: There are examples of different protocols whose behavior seem to
us, on an intuitive level, to be quite similar. For example, there are
several variants of the well known Bakery Algorithm of Lamport that
``look'' alike. How can one express in a formal way such similarities, and
thus help in classifying protocols? We contend that Tarskian structures
(rather than temporal logic structures) can provide a reasonable answer.