The Tempo Project:
Formal Support for the Specification and Construction of Distributed Multimedia Systems
Contents
Project undertaken at:
Computing Department, Lancaster University, Bailrigg, Lancaster, LA1 4YR
Dates: October 1990 - September 1993.
Participants of Tempo were:
Howard Bowman (now at the University of Kent, Canterbury)
The aims of the Tempo project were:
to investigate the use of a variety of formal specification techniques in the demanding area of distributed, multimedia systems architectures,
to focus on formal description techniques (FDTs), but to also consider alternative techniques, and
to carry out work within the framework laid down by emerging Open Distributed Processing (ODP) standardisation.
The project initially considered the nature of distributed multimedia systems and presented a set of requirements for the specification of such systems. A wide range of formal specification techniques were considered, including software engineering techniques, state transition approaches, real-time specification languages and logic-based techniques. Particular attention was given to process algebraic techniques, including LOTOS and its timed extensions.
The approach developed under Tempo for the specification of distributed multimedia systems was a dual-language approach some and based on the principle of maintaining a separation of concerns. The methodology involved partitioning a system into functional and non-functional (time-critical) components. LOTOS was used for the specification of the functional behaviour of the system (called abstract behaviour), whilst a real-time temporal logic (QTL) was developed for the specification of the time-critical properties within the system (called real-time assumptions). These components together specified the behaviour of the system. The logic QTL could also be used to specify requirements over the system, and techniques were developed to check the satisfiability of a formula and whether or not a system met a given requirement.
Blair, G. S., L. Blair, H. Bowman, A. G. Chetwynd, "Formal specification of distributed multimedia systems", London: UCL Press, 1998.
Blair, G. S., L. Blair, J.-B. Stefani, "A specification architecture for multimedia systems in open distributed processing", Computer Networks and ISDN Systems 29, Amsterdam: Elsevier, 1997. gzipped postscript
Blair, L., "Formal specification and verification of distributed multimedia systems", PhD thesis, Department of Computing, Lancaster University, 1995.
Blair, L., G. S. Blair, H. Bowman, A. G. Chetwynd, "Formal specification and verification of multimedia systems in open distributed processing", Computer Standards and Interfaces 17, 413-36, Amsterdam: Elsevier, 1995. gzipped postscript
Bowman, H., G. S. Blair, L. Blair, A. G. Chetwynd, "A formal description technique supporting expression of quality of service and media synchronisation", Lecture Notes in Computer Science 882, 145-67, Berlin: Springer, 1994.
Bowman, H., G. S. Blair, L. Blair, A. G. Chetwynd, "Formal description of distributed multimedia systems: an assessment of potential techniques", Computer Communications 18(12), 964-77, Amsterdam: Elsevier, 1995.
Bowman, H., G. S. Blair, L. Blair, A. G. Chetwynd, "Time versus abstraction in formal description", In Proceedings of the Sixth International Conference on Formal Description Techniques (FORTE'93), R. L. Tenney, P. D. Amer, M. U. Uyar (eds), 467-82, Amsterdam: Elsevier, 1994.
Drayton, L., A. G. Chetwynd, G. S. Blair, "An introduction to LOTOS through a worked example", Computer Communications 15(2), 70-85, Butterworth-Heinemann, March 1992.
Further information on other related projects can be found in:
Any comments/questions on this page to: lb@comp.lancs.ac.uk
Last change: January 1998 (L.B.)