Tools for the analysis and modeling of complex systems must be able to support the extensibility of formalisms, reusability of models and customization of formalism compositions. From this perspective, SIMTHESys (Structured Infrastructure for Multiformalism modeling and Testing of Heterogeneous formalisms and Extensions for SYStems) is a new approach to the specification of performability orien...

Analytical modeling plays a crucial role in the analysis and design of computer systems. Stochastic Petri Nets represent a powerful paradigm, widely used for such modeling in the context of dependability, performance and performability. Many structural and stochastic extensions have been proposed in recent years to increase their modeling power, or their capability to handle large systems. This...

This paper discusses software reusability strategies for performance and reliability modeling tools. Special emphasis is on web-embedded tools, and the potential interaction between such tools. We present the system analysis tools (SAT) application programming interface , which allows for quickly embedding existing tools in the web, and generally simpliies programming analysis tools by structur...

Since the early 1970’s a number of models have been proposed for estimating software reliability. However, the realism of many of the underlying assumptions and the applicability of these models continue to be questioned. Our research work was motivated by the fact that although there are practical situations in which the assumption of independence among successive software failures could be ea...

Analytical modeling is a crucial part in the analysis and design of computer systems. Stochastic Petri Nets represent a powerful tool, widely used for dependability, performance and performability modeling. Many structural and stochastic extensions have been proposed so as to increase their modeling power. In this paper we review the main structural and stochastic extensions of Petri nets, by p...

Wireless Sensor Network (WSN) applications, there may be many low-powered sensor nodes which can communicate with each other by wireless techniques. Due to limited power supply, the satisfiability of performability properties, which include energy constraints especially, must be confirmed in design phase. This will help one to avoid implementing impracticable designs. A typical performability p...

Many embedded systems behave as discrete-time semi-Markov processes (DTSMPs). For those systems, performability measures, especially when specified as an accumulated reward, are often difficult to evaluate analytically. In this article, we informally describe an approach that uses a recurrence-relation-based (RRB) reward model for performability evaluation of systems exhibiting DTSMP behavior. ...

This paper discusses software reusability strategies for per formance and reliability modeling tools Special emphasis is on web embedded tools and the potential interaction between such tools We present the system analysis tools SAT application programming in terface which allows for quickly embedding existing tools in the web and generally simpli es programming analysis tools by structured reu...

MDWNsolver is a framework for system modeling and optimization of performability measures based on Markov Decision Petri Net (MDPN) and Markov Decision Well-formed Net (MDWN) formalisms, two Petri Net extensions for high level specification of Markov Decision Processes (MDP). It is integrated in the GreatSPN suite which provides a GUI to design MDPN/MDWN models. From the analysis point of view,...

Recently, application of network systems ( e.g. , cloud computing systems) is increasingly prevalent for achieving integration, sharing and efficient utilization various resources. A parallel task in a system has multiple subtasks that can be executed different servers parallel. However, failures any subtask inevitably result the entire cannot complete. To avoid such situation, create some copi...