Formal Description Techniques and Protocol Specification, Testing and Verification addresses formal description techniques (FDTs) applicable to distributed systems and communication protocols. It aims to present the state of the art in theory, application, tools and industrialization of FDTs. Among the important features presented are: FDT-based system and protocol engineering; FDT-application to distributed systems; Protocol engineering; Practical experience and case studies. Formal Description Techniques and Protocol Specification, Testing and Verification comprises the proceedings of the Joint International Conference on Formal Description Techniques for Distributed Systems and Communication Protocols and Protocol Specification, Testing and Verification, sponsored by the International Federation for Information Processing, held in November 1998, Paris, France. Formal Description Techniques and Protocol Specification, Testing and Verification is suitable as a secondary text for a graduate-level course on Distributed Systems or Communications, and as a reference for researchers and practitioners in industry.

FORTE/PSTV '97 addresses Formal Description Techniques (FDTs) applicable to Distributed Systems and Communication Protocols (such as Estelle, LOTOS, SDL, ASN.1, TTCN, Z, Automata, Process Algebra, Logic). The conference is a forum for presentation of the state-of-the-art in theory, application, tools and industrialization of FDTs, and provides an excellent orientation for newcomers.

Formal Methods for Protocol Engineering and Distributed Systems addresses formal description techniques (FDTs) applicable to distributed systems and communication protocols. It aims to present the state of the art in theory, application, tools an industrialization of FDTs. Among the important features presented are: FDT-based system and protocol engineering; FDT application to distributed systems; Protocol engineeering; Practical experience and case studies. Formal Methods for Protocol Engineering and Distributed Systems contains the proceedings of the Joint International Conference on Formal Description Techniques for Distributed Systems and Communication Protocols and Protocol Specification, Testing, and Verification, which was sponsored by the International Federation for Information Processing (IFIP) and was held in Beijing, China, in October 1999. This volume is suitable as a secondary text for a graduate level course on Distributed Systems or Communications, and as a reference for researchers and industry practitioners.

FORTE/PSTV '97 addresses Formal Description Techniques (FDTs) applicable to Distributed Systems and Communication Protocols (such as Estelle, LOTOS, SDL, ASN.1, TTCN, Z, Automata, Process Algebra, Logic). The conference is a forum for presentation of the state-of-the-art in theory, application, tools and industrialization of FDTs, and provides an excellent orientation for newcomers.

th The 20 anniversary of the IFIP WG6. 1 Joint International Conference on Fonna! Methods for Distributed Systems and Communication Protocols (FORTE XIII / PSTV XX) was celebrated by the year 2000 edition of the Conference, which was held for the first time in Italy, at Pisa, October 10-13, 2000. In devising the subtitle for this special edition --'Fonna! Methods Implementation Under Test' --we wanted to convey two main concepts that, in our opinion, are reflected in the contents of this book. First, the early, pioneering phases in the development of Formal Methods (FM's), with their conflicts between evangelistic and agnostic attitudes, with their over optimistic applications to toy examples and over-skeptical views about scalability to industrial cases, with their misconceptions and myths . . . , all this is essentially over. Many FM's have successfully reached their maturity, having been 'implemented' into concrete development practice: a number of papers in this book report about successful experiences in specifYing and verifYing real distributed systems and protocols. Second, one of the several myths about FM's - the fact that their adoption would eventually eliminate the need for testing - is still quite far from becoming a reality, and, again, this book indicates that testing theory and applications are still remarkably healthy. A total of 63 papers have been submitted to FORTEIPSTV 2000, out of which the Programme Committee has selected 22 for presentation at the Conference and inclusion in the Proceedings.

The main purpose of this paper is to contribute to the discussion about the design of computer and communication systems that can aid the management process. 1.1 Historical Overview We propose that Decision Support System can be considered as a design conception conceived within the computer industry to facilitate the use of computer technology in organisations (Keen, 1991). This framework, built during the late 1970s, offers computer and communication technology as support to the decision process which constitutes, in this view, the core of the management process. The DSS framework offers the following capabilities: • Access: ease of use, wide variety of data, analysis and modelling capacity. • Technological: software gel)eration tools. • Development modes: interactive and evolutionary. Within this perspective, computer and communication technologies are seen as an amplification of the human data processing capabilities which limit the decision process. Thus, the human being is understood metaphorically as a data processing machine. Mental processes are associated with the manipulation of symbols aOO human communication to signal transmission.

FORTE 2001, formerly FORTE/PSTV conference, is a combined conference of FORTE (Formal Description Techniques for Distributed Systems and Communication Protocols) and PSTV (Protocol Specification, Testing and Verification) conferences. This year the conference has a new name FORTE (Formal Techniques for Networked and Distributed Systems). The previous FORTE began in 1989 and the PSTV conference in 1981. Therefore the new FORTE conference actually has a long history of 21 years. The purpose of this conference is to introduce theories and formal techniques applicable to various engineering stages of networked and distributed systems and to share applications and experiences of them. This FORTE 2001 conference proceedings contains 24 refereed papers and 4 invited papers on the subjects. We regret that many good papers submitted could not be published in this volume due to the lack of space. FORTE 2001 was organized under the auspices of IFIP WG 6.1 by Information and Communications University of Korea. It was financially supported by Ministry of Information and Communication of Korea. We would like to thank every author who submitted a paper to FORTE 2001 and thank the reviewers who generously spent their time on reviewing. Special thanks are due to the reviewers who kindly conducted additional reviews for rigorous review process within a very short time frame. We would like to thank Prof. Guy Leduc, the chairman of IFIP WG 6.1, who made valuable suggestions and shared his experiences for conference organization.