Preface Volume 63

AbstractThis volume contains the Proceedings of the First Workshop on Security of Mobile Multiagent Systems (SEMAS'2001). The Workshop was held in Montreal, Canada on May 29, 2001, as satellite event to the 5th International Conference on Autonomous Agents 2001The far reaching influence of the Internet has resulted in an increased interest in agent technologies, which are poised to play a key role in the implementation of successful Internet and WWW-based applications in the future. While there is still considerable hype concerning agent technologies, there is also an increasing awareness of the problems involved. Although there is a large body of work on cryptographic techniques that provide basic building-blocks to solve specific security problems, relatively little work has been done in investigating security in the multiagent system context. The introduction of mobile software agents significantly increases the risks involved in Internet and WWW-based applications. The aim of this workshop was to bring together people from the two relevant research fields, software security and agent-oriented programming. This volume covers actual research papers on security protocols and security policies to enforce security of mobile or multiagent systems but also introduces ideas how to use mobile agents to ensure security of a distributed system.The papers in this volume were reviewed by the program committee consisting, besides editor, of Sahin Albayrak(Technical University Berlin)David Basin(Department of Computer Science, University of Freiburg)Ciaran Bryce(University of Geneve)Hans-Juergen Buerckert(German Research Center for Artificial Intelligence, DFKI)Guenther Karjoth(IBM Research Zuerich)Luc Moreau(Department of Computer Science, University of Southhampton)Volker Roth(Fraunhofer Gesellschaft IGD, Darmstadt)Helmut Schwigon(Bundesamt fuer Sicherheit in der Informationstechnik, BonnVipin Swarup(The MITRE Corp., Boston)Christian Tschudin(Uppsala University)Jan Vitek(Purdue University)This volume will be published as volume 63 in the series Electronic Notes in Theoretical Computer Science (ENTCS). This series is published electronically through the facilities of Elsevier Science B.V. and its auspices. The volumes in the ENTCS series can be accessed at the URL http://www.elsevier.nl/locate/entcsWe are very grateful to the following persons, whose help has been crucial for the success of CMCS'2000: Adele E. Howe, for her help with the organization of the Workshop as satellite event of AA'2001 and Mike Mislove, one of the Managing Editors of the ENTCS series, for his assistance with the use of the ENTCS style files.December 15, 2001 Dieter Hutte

Maude: specification and programming in rewriting logic

Maude is a high-level language and a high-performance system supporting executable specification and declarative programming in rewriting logic. Since rewriting logic contains equational logic, Maude also supports equational specification and programming in its sublanguage of functional modules and theories. The underlying equational logic chosen for Maude is membership equational logic, that has sorts, subsorts, operator overloading, and partiality definable by membership and equality conditions. Rewriting logic is reflective, in the sense of being able to express its own metalevel at the object level. Reflection is systematically exploited in Maude endowing the language with powerful metaprogramming capabilities, including both user-definable module operations and declarative strategies to guide the deduction process. This paper explains and illustrates with examples the main concepts of Maude's language design, including its underlying logic, functional, system and object-oriented modules, as well as parameterized modules, theories, and views. We also explain how Maude supports reflection, metaprogramming and internal strategies. The paper outlines the principles underlying the Maude system implementation, including its semicompilation techniques. We conclude with some remarks about applications, work on a formal environment for Maude, and a mobile language extension of Maude

A Multi-Core Solver for Parity Games

We describe a parallel algorithm for solving parity games,\ud with applications in, e.g., modal mu-calculus model\ud checking with arbitrary alternations, and (branching) bisimulation\ud checking. The algorithm is based on Jurdzinski's Small Progress\ud Measures. Actually, this is a class of algorithms, depending on\ud a selection heuristics.\ud \ud Our algorithm operates lock-free, and mostly wait-free (except for\ud infrequent termination detection), and thus allows maximum\ud parallelism. Additionally, we conserve memory by avoiding storage\ud of predecessor edges for the parity graph through strictly\ud forward-looking heuristics.\ud \ud We evaluate our multi-core implementation's behaviour on parity games\ud obtained from mu-calculus model checking problems for a set of\ud communication protocols, randomly generated problem instances, and\ud parametric problem instances from the literature.\ud \u

Platform Dependent Verification: On Engineering Verification Tools for 21st Century

The paper overviews recent developments in platform-dependent explicit-state LTL model checking.Comment: In Proceedings PDMC 2011, arXiv:1111.006