Formal Specification and Verification of Mobile Agent Systems

Mobile agent systems offer efficiency and flexibility as a design paradigm. These two characteristics allow to these systems to be an adequate solution for many problems. These systems are used in many critical domains. This expansion, in use, obliges designers to insure the reliability and correctness of such systems. Formal methods can be used to verify thecorrectness of these systems. This paper presents a formal specification and verification of mobile agent systems using the High Order π-calculus. The verification exploits the twotools UPPAAL and SPIN

A new Itinerary planning approach among multiple mobile agents in wireless sensor networks (WSN) to reduce energy consumption

one of the important challenges in wireless sensors networks (WSN) resides in energy consumption. In order to resolve this limitation, several solutions were proposed. Recently, the exploitation of mobile agent technologies in wireless sensor networks to optimize energy consumption attracts researchers. Despite their advantage as an ambitious solution, the itineraries followed by migrating mobile agents can surcharge the network and so have an impact on energy consumption. Many researches have dealt with itinerary planning in WSNs through the use of a single agent (SIP: Single agent Itinerary Planning) or multiple mobile agents (MIP: Multiple agents Itinerary Planning). However, the use of multi-agents causes the emergence of the data load unbalancing problem among mobile agents, where the geographical distance is the unique factor motivating to plan the itinerary of the agents. The data balancing factor has an important role especially in Wireless sensor networks multimedia that owns a considerable volume of data size. It helps to optimize the tasks duration and thus optimizes the overall answer time of the network.  In this paper, we provide a new MIP solution (GIGM-MIP) which is based not only on geographic information but also on the amount of data provided by each node to reduce the energy consumption of the network. The simulation experiments show that our approach is more efficient than other approaches in terms of task duration and the amount of energy consumption

Extending Petri Nets for Modeling and Analysis of Reconfigurable Systems

Petri nets are a formal and graphical tool proposed to model and to analyze behavior of concurrent systems. In its basic version, this model is defined as a fixed graph, where the behavior of the system is modeled as the marking of the graph that changes over time. This constraint makes the Petri Nets a poor tool to deal with reconfigurable systems where the structure of the system can change as its behavior, during time. Many extended Petri nets were proposed to deal with this weakness. The aim of this work is to present an extension where the structure of the graph can be highly flexible. This flexibility gives a rich model with complex behaviors, not allowed in previous extensions. The second aim is to prove that even these behaviors are so complex; they can be encoded in other models and so be analyzed

Modelling and analysis of mobile computing systems: An extended Petri Nets formalism

In its basic version, Petri Nets are defined as fixed graphs, where thebehaviour of the system is modelled as the marking of the graph which changes overtime. This constraint makes the Petri Nets a poor tool to deal with reconfigurablesystems as mobile computing systems, where the structure of the system can changeas its behaviour, during time. Many extended Petri nets were proposed to deal withthis weakness. The aim of this work is to present a new extension of Petri Nets, wherethe structure of the graph can be highly flexible. This flexibility gives a rich modelwith complex behaviours, not allowed in previous extensions. The second aim is toprove that even these behaviours are so complex; they can be translated into otherlow level models (as Coloured Petri Nets [21]) and so be analysed. This translationexploits Dynamic Petri Nets [11] as an intermediary representation between our modeland Coloured Petri Nets.100

A New Hybrid Access Control Model for Security Policies in Multimodal Applications Environments

New technologies as cloud computing and internet of things (IoT) has expanded the range of multimodal applications. This expansion, in several computing and heterogeneous environments, makes access control an important issue in multimodal applications. Indeed, a variety of access control models have been developed to address different aspects of security problems. The two most popular basic models are: Role Based Access Control (RBAC) and Attribute Based Access Control (ABAC). The both models RBAC and ABAC have their specific features and they can complement each other. For that, providing a hybrid model which considers both concepts "roles" as well as "attributes" has become an important research topic. This paper proposes a new access control model based principally on roles, attributes, access modes and the type of resources. An empirical method is applied to compare the new proposed model versus three existing models: RBAC, ABAC, and the hybrid model Attribute Enhanced RBAC (AERBAC). The results of the empirical method demonstrate that the new proposed model acquires the advantages of the two models RBAC and ABAC and avoids their limitations. In fact, the new proposed model reduces the complexity of security policies and allows expressing the fine granularity of systems without any explosion in the number of roles or rules in the security policy

Dynamic GSPNs: formal definition, transformation towards GSPNs and formal verification

International audienc

A comparative analysis of adaptive consistency approaches in cloud storage

International audienceNoSQL storage systems are used extensively by web applications and provide an attractive alternative to conventional databases due to their high security and availability with a low cost. High data availability is achieved by replicating data in different servers in order to reduce access time lag, network bandwidth consumption and system unreliability. Hence, the data consistency is a major challenge in distributed systems. In this context, strong consistency guarantees data freshness but affects directly the performance and availability of the system. In contrast, weaker consistency enhances availability and performance but increases data staleness. Therefore, an adaptive consistency strategy is needed to tune, during runtime, the consistency level depending on the criticality of the requests or data items. Although there is a rich literature on adaptive consistency approaches in cloud storage, there is a need to classify as well as regroup the approaches based on their strategies. This paper will establish a set of comparative criteria and then make a comparative analysis of existing adaptive consistency approaches. A survey of this kind not only provides the user/researcher with a comparative performance analysis of the approaches but also clarifies the suitability of these for candidate cloud systems