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The following topics are dealt with: complex computer systems engineering real-time systems; modeling and verification; safety and security; context awareness and ubiquitous computing; formal languages; and software architecture.
We present results from the second pilot project in the international Verification Grand Challenge: a formally verified specification of a POSIX-compliant file store using the Z/Eves theorem prover. The project's overall objective is to build a verified file store for space-flight missions. Our specification of the file store is based on Morgan & Sufrin's specification of the UNIX filing system;...
Traditional, standards-based approaches to certification are hugely expensive, of questionable credibility when development is outsourced, and a barrier to innovation. This paper is a call and a manifesto for new approaches to certification. We start by advocating a goal-based approach in which unconditional claims delivered by formal methods are combined with other evidence in multi-legged cases...
This paper presents supervisory control theory in a process-algebraic setting, and proposes a way of synthesising modular supervisors that guarantee nonblocking. The framework used includes the possibility of hiding actions which results in nondeterminism. As modularity crucially depends on the process equivalence used, the paper studies possible equivalences and points out that, in order to be consistent...
For many systems, timing aspects are essential. Therefore, when modelling these systems, time should somehow be represented. In the past, many timed process algebras have been developed, using untimed process algebras as initial inspiration. In this paper, we take another approach, considering the possibility to model timing aspects with an untimed process algebra. The advantage is that the algebra...
This paper focuses on automated verification to check whether the behavior of a Web application conforms to its design. The Object Relation Diagram as design model and the Kripke structure as implementation model are employed to describe the object structure and the external observable behavior of a Web application respectively. We propose an approach to automatically generating from the design model...
Identifying and resolving design problems in the early design phase can help ensure software quality and save costs. There are currently few tools for analyzing designs expressed using the Unified Modeling Language (UML). Tools such as OCLE and USE support analysis of static structural properties. These tools provide mechanisms for checking instance models against invariant properties expressed using...
Different from traditional transactions, a compensable transaction relies on compensations to amend partial execution whenever an error occurs. The compensation is preserved on successful completion of its forward transaction for possibly later use. In this paper, we pay attention to the compositional structure of compensable transactions. Except for sequential and parallel compositions, other useful...
Semantic Web services, one of the most significant research areas within the semantic Web vision, has attracted increasing attention from both the research community and industry. The Web service modelling ontology (WSMO) has recently been proposed as an enabling framework for the total/partial automation of the tasks (e.g., discovery, selection, composition, mediation, execution, monitoring, etc...
Numerous software verification and validation (V&V) techniques and tools exist to analyse requirements, designs and implementations of software systems. These V&V technologies range from relatively lightweight ones, such as inspection and testing, to more heavyweight technologies based on formal methods and theorem proving. For complex systems, a significant part of the cost and effort for...
Modern online multiplayer games are complex heterogeneous distributed systems comprised of servers and untrusted clients, which are often engineered under considerable commercial pressures. Under these conditions, security breaches allowing clients to employ illegal behaviours have become common; current commercial approaches have limited capabilities for reacting rapidly to such threats. This paper...
Reduction methods developed by Lipton, Lamport, Cohen, and others, allow one to reason about concurrent programs at various levels of atomicity. An action which is considered to be atomic at one level may be implemented by more complex code at the next level. We can show that certain properties of the program are preserved by first showing that the property holds when the expanded code is executed...
Fault tolerance in information security devices is difficult to establish due to the large number of possible interactions in the device (e. g. embedded code, boolean logic, electromagnetic interference, etc.) In previous work we examined information flow as a graph problem by composing orthogonal views of the device under analysis. In other work we used fault-tree analysis to reason about information...
The sensor network service has emerged as a new technical research area. The sensor network service provides useful functions to the user by sensing the condition of physical entities. One important issue that is rarely addressed by current studies on the sensor network service is that they only use sensor-derived data to achieve local service goals. However, once external users can discover globally...
With the increased interest in multi-user systems with distributed decision making tasks, such as network centric warfare and free-flight air traffic control, the concept of shared situation awareness (SSA) has become more important. SSA relates to the awareness that different operators have of the system state and the information needs of their team-mates, in order to coordinate their actions effectively...
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