In this paper we summarize our experiences in building and integrating new generation, formal-methods based CASE tools to yield pragmatic improvements in software engineering processes in the telecommunication industry. We define an accelerated development methodology (ADM) for the specification, design, testing and re-engineering of telecommunications software. We identify two of the most significant barriers to adoption of tools and formal methods to speed up software development, namely the requirements engineering barrier and the legacy code re-engineering barrier, and show how the ADM methodology helps to overcome these barriers and improve time-to-market for telecommunications software. Our ADM methodology is based on the most widely accepted formal languages standardized by the International Telecommunications Union (ITU): i) a scenario description language called Message Sequence Charts (MSC), ii) an EFSM-based Specification and Description Language (SDL), iii) an executable test description language called Tree and Tabular Combined

In this paper we investigate the problem of designing embedded decentralized discrete-event con-trollers over communication networks. It is assumed that there is a path between every pair of processes in the network. The control objective is specified by a prefix-closed language which is controllable and observable, but not coobservabe. The paper is focused on communication among processes necessary to meet the control objective. As such, process models are left unspecified; it is only required that disabling any of the controllable events does not block communication among processes. Our findings support the idea that in the presence of ideal communication channels the protocol design for non-coobservable specifications can be reduced to the synthesis of communicating decentralized supervisors, and we propose solutions for a restricted class of problems. Also a couple of positive results are stated for the case where channels are unreliable. Index Terms decentralized supervisory control, discrete-event systems, protocol design. I.

An innovative methodology for the efficient design of communication controller hardware for popular protocols such as ATM, USB or CAN is proposed. In our approach, controller hardware in form of RTL models is synthesized from a formal specification of a communication protocol. The difference to previously published work related to hardware synthesis techniques from protocol specifications is that in our approach a complete communication architecture consisting of both the interacting transaction producer and the consumer controllers, as well as the interconnect between them, are synthesized from one single protocol specification in the same synthesis tool run, thus ensuring conformity of all producer and consumer controllers to the protocol specification while tremendously reducing the modeling effort for the controller specifications. The formalism used for protocol specification and a corresponding hardware synthesis algorithm from such specifications are presented. The methodology has been applied to the design of various communication controllers including IEC14443 Wireless SmartCard, ATM and CAN. The novelty and efficiency of our methodology is demonstrated through comparison to State-of-TheArt protocol synthesis tools such as [10].

Abstract. In this paper we argue that self-modifying code can become a better strategy for realizing long-lived autonomous software systems than static code, regardless how well it was validated and tested. We base our discussion on three facets – self-repairing software, adaptive software and networked systems – for which we point out ongoing and related work before presenting a roadmap towards a controlled framework for self-modifying code.

. Protocol synthesis is used to derive a specication of a distributed system from the specication of the services to be provided by the system to its users. Maintaining such a system involves applying frequent minor modications to the service specication due to changes in the user requirements. In order to reduce the maintenance costs of such a system, we present an original method that consists of a set of rules that avoid complete protocol synthesis after these modications. These rules are given for a system modeled as an extended Petri net. An application example is given along with some experimental results. 1 Introduction Synthesis methods have been used (for surveys see [5, 6]) to derive a specication of a distributed system (hereafter called protocol specication) automatically from a given specication of the service to be provided by the distributed system to its users (called service specication). The service specication is written like a program of a centra...

ion allows a designer to focus on some aspects of interest, while ignoring other aspects. Well-defined abstraction levels determine global sequences of aspects to be considered, providing guidance to designers when performing instances of the design process. When defining a design methodology, we have to carefully consider the level of detail in which its milestones are defined. Too detailed global design objectives and choices may restrict the applicability of the methodology; too general global design objective and choices may make the methodology useless for realistic applications. We conclude that there must be a certain compromise between the degree of freedom allowed by the methodology and the amount of guidance it provides. A realistic design methodology should define global objectives and choices in a more concrete way than for example the waterfall model (e.g. [1], [2]) in which design, implementation, realization, testing, production, maintenance subsequent phases are identi...

This thesis summarizes the work of the author as a master/doctor student of Osaka University on the implementation of service specifications on distributed computing systems. In a distributed computing system, multiple computers, called protocol entities, communicate with each other, exchanging messages for synchronization and data transfer. On the implementation phase of such a distributed system, the behavior of all the protocol entities must be specified. The specification of each protocol entity is called a protocol entity specification and the set of all the protocol entity specifications is called a protocol specification. In general, the control flow of each protocol entity specification may become complicated, since it contains communications among other protocol entities for cooperative computing. Therefore, it is hard for designers to describe a protocol specification directly without mistake. In the recent years, for designing reliable distributed computing systems, many approaches...

ABSTRACT. Communications protocols re-synthesis involves the augmentation of existing synthesized protocol entities given a modified formal service definition. This process would reduce the time required for deploying enhanced and frequently modified services. In this paper, we introduce a re-synthesis technique based on a service-oriented protocol synthesis method introduced earlier [1]. Re-synthesis can be applied in various distributed systems application areas, such as discrete event distributed controllers, communications protocol converters, and distributed software agents.