The functional modeling of telecommunications systems requires an early emphasis on behavioral aspects. In the first stages of common development processes, telecommunications features, services, and functionalities are defined in terms of informal requirements and visual descriptions. As these descriptions grow and evolve, they quickly become error-prone and difficult to understand. Conse-quently, designs can hardly be checked or validated against such descriptions.

This thesis proposes an innovative methodology named Specification-Validation Approach with LOTOS and UCMs (SPEC-VALUE), which tackles these problems using two notations. The first notation, called Use Case Maps (UCMs), is used to capture and integrate functional requirements in terms of causal scenarios. Scenarios describing system views, uses, and services are becoming a common method of capturing functional requirements of reactive and distributed systems. They are particularly appropriate to represent behavioral aspects so that various stakeholders can understand them. In addition to these general properties of scenarios, UCMs can help reasoning about system-wide functionalities at a high level of abstraction. Integrating UCMs together also helps avoiding many undesirable interactions, usually resulting from the composition of different scenarios, before the generation of prototypes.

The second notation is the formal specification language LOTOS. It will be shown that UCM scenarios bound to architectural components can be translated into high-level LOTOS specifications. In turn, these specifications can be used as prototypes to animate UCMs and to validate high-level designs against requirements systematically through numerous techniques, including functional testing based on UCMs. LOTOS possesses powerful testing concepts and tools that excel at detecting errors and undesirable interactions. LOTOS represents a judicious formalism here because it supports many UCM constructs directly, and it complements most of UCM’s weak areas related to the analysis of systems.

SPEC-VALUE introduces theories and techniques for constructing LOTOS specifications from UCMs, for deriving validation test cases from UCMs, and for measuring the structural coverage of LOTOS specifications achieved during validation. An ongoing example is used to illustrate these concepts: the Tiny Telephony System. The thesis validates the SPEC-VALUE methodology through its application to various telecommunications systems (Group Communication Server, Group-Call service of GPRS, feature interactions, agent-based simplified basic call, and GSM’s MAP protocol), and concludes with an assessment of these experimental results.

-- DanielAmyot - 11 Oct 2005


  • Please feel free to discuss this article directly on this page. Constructive comments are welcomed! Please sign your TWiki name.

FormForVirtualLibrary edit

Title Specification and Validation of Telecommunications Systems with Use Case Maps and LOTOS
Authors D. Amyot
Type Thesis
Conference/Journal Title
Publisher SITE, University of Ottawa
Month September
Year 2001
Pages 390
Keywords LOTOS, Specification, SPEC-VALUE, UCM, Validation,
Topic attachments
I Attachment Action Size Date Who Comment
da_phd.pdfpdf da_phd.pdf manage 2 MB 11 Oct 2005 - 10:49 DanielAmyot D. Amyot's Ph.D. thesis
defense20010817.zipzip defense20010817.zip manage 254 K 11 Oct 2005 - 10:51 DanielAmyot Ph.D. Defense Presentation
Topic revision: r2 - 08 Mar 2010, DanielAmyot
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding Foswiki? Send feedback