The two unique benefits of Concurrent and Comparative Discrete Event Simulation are: speed, which is usually 1000 to 10 000 times faster than conventional discrete event simulation; and methodology, which permits the concurrent/comparative simulation of many thousands of experiments. One idea is that a one-for-many experiment, called the reference, is simulated in its entirety, while all others are simulated only where they differ from the reference. A second idea extends the first one; many one-for-many experiments will be significantly more efficient than only one experiment. These two ideas result in tremendous efficiencies, permitting the concurrent simulation of tens of thousands of experiments. The material in the book covers a vast application area in the scientific and business world. For example, in the design experimentation of nuclear power plant operations, many scenarios can be simulated to derive desirable designs or safe operating procedures. Concurrent fault simulation is already a mature technique in the computer aided design of digital systems. Concurrent/Comparative Simulation (CCS) of several instruction sets for a computer can help a designer in making performance tradeoffs. One of the most powerful future applications for CCS/MDCCS (Concurrent and Comparative Simulation/Multi-Domain Concurrent and Comparative Simulation) will be in the testing and debugging of computer programs.

Concurrent simulation is over twenty years old. During that pe riod it has been widely adopted for the simulation of faults in digital circuits, for which it provides a combination of extreme efficiency and generality . Yet, it is remarkable that no book published so far presents a correct and sufficiently detailed treatment of concurrent simulation. A first reason to welcome into print the effort of the authors is, therefore, that it provides a much needed account of an important topic in design automation. This book is, however, unique for sev eral other reasons. It is safe to state that no individual has contrib uted more than Ernst Ulrich to the development of digital logic simulation. For concurrent simulation, one may say that Ernst has contributed more than the rest of the world. We would find such a claim difficult to dispute. The unique experience of the authors con fers a special character to this book: It is authoritative, inspired, and focused on what is conceptually important. Another unique aspect of this book, perhaps the one that will be the most surprising for many readers, is that it is strongly projected towards the future. Concurrent simulation is presented as a general experimentation methodology and new intriguing applications are analyzed. The discussion of multi-domain concurrent simulation-- recent work of Karen Panetta Lentz and Ernst Ulrich---is fascinat ing."