Foreword

Among COST European research actions in the area of telecommunications in the period 1994-1996, Action COST 247 ``Verification and Validation Methods for Formal Descriptions'' is the only one concerned with achieving the important design goal - correct communication software. The co-ordination of national efforts to analyse, classify and come up with new and efficient techniques and tools for concurrent software verification and validation in order to enhance the applicability of formal methods to practical examples and thus improve the efficiency of software production cycle for complex distributed systems is stated as its purpose.

In the third year of the Action, on June 17-19, 1996, the International Workshop entitled ``Applied Formal Methods in System Design'' was organized in Maribor, Slovenia. Its aim was to provide a forum for COST 247 participants from various European countries to present, discuss and compare their work related to the Action. Scientific programme of the workshop consisted of an invited lecture on commercial verification, given by Dr. Robert Kurshan from AT&T Bell Laboratories, Murray Hills, New Jersey, USA, and of 21 regular papers, ranging from the system design using SDL, verification with LOTOS and model checking, to protocol testing. Three of the presentations dealt with the verification of a bounded retransmission protocol, that had been suggested to be tackled by the participants as a common example in order to compare different verification techniques. Demonstrations of two software tools for formal specification and verification of concurrent systems were given. First, CAESAR/ALDEBARAN tool developed at INRIA/VERIMAG in France was presented. The second tool was TE-LOLA: A Type Extended Lola Prototype, developed at the Department of Telematics Engineering, Technical University of Madrid, Spain. The regular COST 247 Management Committee Meeting took place on the last two days of the workshop.

Researchers from 14 different countries were attending the workshop. Scientific contributions came from 11 different countries. The Proceedings contain an extended abstract of the invited lecture given at the workshop, and 17 out of 21 presented regular papers were included in it after the proofreading.

The workshop was jointly organized by Action COST 247, Faculty of Electrical Engineering and Computer Science at University of Maribor, IEEE Slovenia Section and IEEE Communications Society Chapter of Slovenia. The main sponsors of the workshop were the European Commission - COST Telecommunications Secretariat and Ministry of Science and Technology, Republic of Slovenia. A sponsorship was also given by Telekom Slovenije, which is the greatest carrier of telecommunication services in Slovenia, and by IskraTel, which is the greatest producer of telecommunication systems including ISDN exchanges in Slovenia. Marand d.o.o, which is an authorized SUN distributor for Slovenia, supported us with SUN computer equipment needed for software tool demonstrations. We thank all of them.

We would like to thank all who have willingly given their time and energy to make the workshop a success, both from the Programme and the Organizing Committee, especially to Ales Casar who has technically prepared the Proceedings for printing.