This volume contains the papers presented at the Tenth SDL Forum, Cop- hagen. SDL is the Speci?cation and Description Language ?rst standardized by the world telecommunications body, the International Telecommunications Union (ITU), more than 20 years ago in 1976. While the original language and domain of application has evolved signi?cantly, the foundations of SDL as a graphical, state-transition and process-communication language for real-time systems have remained. Today SDL has also grown to be one notation in the set of uni?ed modelling languages recommended by the ITU (ASN.1, MSC, SDL,...

This volume contains the papers presented at the 11th SDL Forum, Stuttgart. As well as the papers, the 11th SDL Forum also hosted a system design competition sponsored by Solinet with a cash prize for the best design. This follows a similar competition at the SAM 2002 workshop (papers published in LNCS 2599). The winning entry from SAM 2002 is described in the last paper in this volume. The SDL Forum was ?rst held in 1982, and then every two years from 1985. Initially the Forum was concerned only with the Speci?cation and Descr- tion Language ?rst standardized in the 1976 Orange Book of the...