An Introduction to Input Output Automata

The input output automaton model has recently been de ned in LT LT as a tool for modeling concurrent and distributed discrete event systems of the sorts arising in computer science Since its introduction the model has been used for describing and reasoning about several di erent types of systems including network resource allocation algorithms communication algorithms concurrent database systems shared atomic objects and data ow architectures This paper is intended to introduce researchers to the model It is orga nized as follows Section contains an overview of the model Section de nes the model formally and examines several illustrative examples concerning candy vending machines Section contains a second example a leader election algo rithm Finally Section contains a survey of some of the uses that have so far been made of the model