We present a graphical toolset for verifying AADL models, which are gaining widespread acceptance in aerospace, automobile and avionics industries for comprehensively specifying safety-critical systems by capturing functional, probabilistic and hybrid aspects. Analyses are implemented on top of mature model checking tools and range from requirements validation to functional verification, safety...

We propose a new method to obtain bounds of dependability, performance or performability measures concerning complex systems modeled by a large Markov model. Its extends previous published techniques mainly designed to the analysis of dependability measures only, and working under more restrictive conditions. Our approach allows to obtain tight bounds of performance measures on certain cases, a...

With the increased attention ATM is receiving to meet the needs of a wide variety of applications, tools are needed to help a network designer focus on the design at hand, rather than to spend time exhaustively learning the tools themselves. This is the concept behind IDEA. This paper introduces \modeling engines" chosen to be integrated into IDEA and presents a user interface for networking de...

It is necessary to have the precise definition of available performance of high availability systems that can represent the availability and performability of the systems altogether. However, the difference between numeric scales of availability and performance metrics such as waiting time makes quantitative evaluation difficult. A number of previous studies on availability do not include a per...

Several high-level extensions have been introduced for Petri nets (PNs). Coloured Petri nets (CPNs) are the most famous high-level extensions of PNs. Stochastic activity networks (SANs) are a stochastic generalization of PNs. These models have widely been used for dependability and performability evaluation purposes and are supported with a few powerful modeling tools. To provide some high-leve...

This paper describes how to employ Multi-Terminal Binary Decision Diagrams (MTBDDs) for the construction and analysis of a general class of models that exhibit stochastic, probabilistic and non-deterministic behaviour. It is shown how the notorious problem of state space explosion can be circumvented by compositionally constructing symbolic (i.e. MTBDD-based) representations of complex systems ...

We describe a novel performability modelling approach which facilitates the efficient solution of performance models extracted from high-level descriptions of systems. The notation which we use for our high-level designs is the UML graphical modelling language. The technology which provides the efficient representation capability for the underlying performance model is the MTBDD-based PRISM pro...

A new model composer is proposed to automatically generate non-anonymous model replicas in the context of performability and dependability evaluation. It is a state-sharing composer that extends the standard anonymous replication composer in order to share the state of a replica among a set of other specific replicas or among the replica and another external model. This new composition operator...

The paper considers reliability analysis for aging multi-state system where the system and its components can have different performance levels ranging from perfect functioning to complete failure. Aging is treated as failure rate increasing during system lifetime. Reliability measures for multi-state system such as mean accumulated performance deficiency, mean number of failures, average avail...

We introduce Stochastic Process Algebras as a novel approach for the structured design and analysis of both the functional behaviour and performabil-ity (i.e performance and dependability) characteristics of parallel and distributed systems. This is achieved by integrating stochastic modelling and analysis into the powerful and well investigated formal description techniques of process algebras...