INFORMXTION SCIENCES 54, 191-218 (1991) zyxwvutsrqponmlkjihgfedcbaZYXWVUT Extended Colored Petri Net: An Efficient Tool for Analyzing Concurrent Systems SAJAL K. DAS* zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFED Department of Computer zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH Sciences, Unir~ersity of North Texas, Denton, Texas 76203-3886 DILIP SARKAR Department of Mathematics and Computer Science, University of Miami, Coral Gables, Florida 33124 V. K. AGRAWAL ISRO Satellite Centre, Bangalore- 017, India and L. M. PATNAIK Department of Computer Science & Automation, Indian Institute of Science, Bangalore- 012, India Communicated by C. V. Ramamoorthy 191 ABSTRACT This paper proposes a novel and simple definition of general colored Petri nets. This definition is coherent with that of (uncolored) Petri nets, preserves the reflexivity of the original net, and is extended to represent inhibitors. Also suggested are systematic and formal merging rules to obtain a well-formed structure of the extended colored Petri net by folding a given uncolored net. Finally, we present a technique to compute colored invariants by selecting colored RP-subnets. On the average, the proposed technique performs better than the existing ones. The analysis procedure is explained through an illustrative example of a three-level interrupt-priority-handler scheme. *To whom all correspondence should be sent. OElsevier Science Publishing Co., Inc. 1991 655 Avenue of the Americas, New York, NY 10010 0020-0255/91/$03.50