Amal Gassara

Towards a multi-scale modeling for architectural deployment based on bigraphs

With the evolution of distributed systems in size and complexity, software deployment remains a challenging task. Despite the existence of several approaches, most of them use informal models that lack a solid mathematic foundation. In this paper, we propose a bigraphical based approach for modeling and formalizing the deployment of distributed applications. This approach relies on multi-scale modeling. So, we start by modeling the first scale with a bigraph. This bigraph is enriched, through a series of reaction rules, until reaching the last scale that represents the deployment architecture.

A bigraphical multi-scale modeling methodology for system of systems

A multi-scale modeling approach for System of Systems design.A formal methodology using Bigraphical reactive systems.A correct by construction approach for describing SoS architectures.An illustration of our methodology with a smart buildings case study. Display Omitted In this paper, we present a multi-scale modeling methodology for software System of Systems (SoS) using the formal technique of bigraphical reactive system. This methodology provides a correct by design approach ensuring the correctness of the SoS architectures. A first scale is defined by the designer. Then, it is refined by successively adding lower scale details. The transition between scales is implemented following a rule-oriented refinement process. The executed rules respect the system constraints ensuring, in this way, the correctness of the obtained scale architectures. Moreover, we address the dynamic aspect of SoS by providing model-based rules of reconfiguration actions. We illustrate our approach with a Smart Buildings case study.

Encoding Bigraphical Reactive Systems into Graph Transformation Systems

In this paper, we present a solution for executing bigraphical reactive systems based on an investigation on graph transformation systems. For this, we encode a bigraph into a ranked graph. This encoding is ensured, formally, by defining a faithful functor that allows to move from bigraph category to ranked graph category. Then, we show that reaction rules can be simulated with graph rules.

A formal method for modeling deployment architectures based on bigraphs

Software deployment is executed according a deployment architecture which describes the allocation of software components to its hardware hosts. In this paper, we tackle the issue of constructing correct deployment architectures for large distributed systems. Actually, such architectures should satisfy various constraints related to the software components and the target environment such as the hierarchical description of components, their connections and the resource constraints. We present a formal method for constructing deployment architectures using a formal language called BRS (Bigraphical Reactive System). This method provides a correct by design approach based on multi-scale modeling ensuring the correctness of the obtained deployment architectures. Following our approach, the designer starts by modeling the first scale architecture which is refined automatically by successively adding smaller scale components until obtaining the last scale deployment architecture.

Describing correct deployment architectures based on a bigraphical multi-scale modeling approach ☆

Abstract In this paper, we propose a formal approach supporting the correct description of deployment architectures and their reconfigurations. According to defined models, correct deployment architectures are generated and one of them is selected to be deployed. This generation process is based on a multi-scale modeling approach adopting Bigraphs and Bigraphical Reactive Systems as a modeling language. In fact, the architecture of a scale is refined by adding the components of the next scale. Then, the obtained architecture is in turn refined and so on, until reaching the last scale. The transition between scales is performed through applying refinement rules. Based on correct by design, the refinement process is executed on a correct scale architecture (respects the defined models) by applying correct rules. So, we ensure that the generated scale architectures are correct. Finally, our approach is illustrated through the case study Smart Home.

A Bigraphical Modeling Methodology for Multi-scale Reconfigurable Systems

In this paper, we propose a multi-scale modeling methodology for software reconfigurable systems using the formal technique of Bigraphical Reactive Systems. This methodology provides a correct by design approach for the description of multi-scale architectures. It is based on a rule-oriented refinement process ensuring the transitions between scales. In fact, a first scale is defined by the designer. Then, it is refined by successively adding lower scale details. The applied rules respect the system constraints ensuring the correctness of the obtained scale architectures. Furthermore, we deal with the dynamic aspect of multi-scale systems by providing model-based rules of reconfigurations. We illustrate our approach with a Smart Buildings case study.

A multi-scale modeling approach for software architecture deployment

For large component-based applications, identifying a valid deployment architecture has emerged as a major challenge. Actually, this deployment architecture (i.e., allocation of software components to its hardware hosts) should satisfy various constraints related to the software components and the target environment such as the hierarchical description of components, their connections and the resource constraints. The numerous constraints make hard to construct manually the correct deployment architecture. In this work, we propose a formal method based on a formal language called BRS (Bigraphical Reactive System) in order to guarantee the correctness of the deployment architecture. Furthermore, in order to support its automatic construction, our proposed method follows a multi-scale modeling. In fact, the designer starts by modeling the first scale architecture which is refined automatically by successively adding smaller scale components until obtaining the deployment architecture at the last scale. This refinement is ensured by applying a set of rules. In this paper, we address communicating systems as a study domain.

A Formal Method for Modeling Deployment Architectures Based on Bigraphs

Software deployment is executed according a deployment architecture which describes the allocation of software components to its hardware hosts. In this paper, we tackle the issue of constructing correct deployment architectures for large distributed systems. Actually, such architectures should satisfy various constraints related to the software components and the target environment such as the hierarchical description of components , their connections and the resource constraints. We present a formal method for constructing deployment architectures using a formal language called BRS (Bigraphical Reactive System). This method provides a correct by design approach based on multi-scale modeling ensuring the correctness of the obtained deployment architectures. Following our approach, the designer starts by modeling the first scale architecture which is refined automatically by successively adding smaller scale components until obtaining the last scale deployment architecture.The increase of mobile and interconnected devices leads to the growth of demands for context aware applications. These applications deployed on top of pervasive environments must adapt themselves to context changes. Context aware applications have to continuously sense their physical environment, and adapt their behavior accordingly. These applications must perform four phases starting by collecting and monitoring context, then analyzing context, deciding adaptation actions and finally executing the planned adaptation actions to deal with the context changes. In this paper, we focus on the second phase.We propose a context analysis approach that relies on different thresholds defined according to the user needs to detect context changes and raise notifications when changes occur. The analysis approach is performed according to three different steps. A context storage step, a context classification step, and a threshold calculation step. Received on 12 December 2014; accepted on 05 March 2015; published on 04 August 2015

Executing bigraphical reactive systems

In order to enable experimentations and simulations of bigraphs, we need an implementation of their dynamic. In this paper, we tackle the matching issue of this task. We present a solution based on an investigation on graph matching. We propose to simulate a bigraphical reactive system (i.e., bigraphs with a set of reaction rules that allow their rewriting) with a graph transformation system. First, we translate a bigraph to a ranked graph. This translation is ensured by defining a faithful functor that allows to move from the bigraph category to the ranked graph category. Then, we show that reaction rules can be simulated with graph rules. Hence, we provide a formal basis allowing to execute bigraph transformations by simulating their translation aiming to use well-established and efficient graph transformation tools.

A tool for modeling SoS architectures using bigraphs

Bigraphs and Bigraphical Reactive Systems have been successfully applied in describing software architectures and modeling applications for context-aware systems and System of Systems. Therefore, it is very important to have an implementation of its dynamic to enable simulations and experimentations. In this paper, we present BiGMTE, a tool for bigraph matching and transformation. The implemented solution is based on an investigation of graph rewriting. In fact, we propose to simulate a bigraphical reactive system (i.e., bigraphs with a set of reaction rules which allow their rewriting) with a graph transformation system. Therefore, we propose two algorithms that encode a bigraph into a graph and a reaction rule into a graph rule. Finally, we give an example of modeling a SoS using BiGMTE.