Mohamed Salah Bouassida

Group Key Management in MANETs

Specific applications like military or public emergency ones require secure group communication in ad hoc environments. The most suitable solution to provide the expected level of security to these services is the provision of a key management protocol. This paper shows the specific challenges towards key management protocols for securing multicast communications in ad hoc networks, and provides a taxonomy of these protocols in MANETs. A new approach, called BALADE, is also presented. It is based on a sequential multi-sources model, and takes into account both localization and mobility of nodes, while optimizing energy and bandwidth consumptions.

Efficient clustering for multicast key distribution in MANETs

Securing multicast communications in ad hoc networks must consider several challenging factors such as high nodes mobility, limited bandwidth and constrained energy. Moreover, the establishment of a key management protocol within ad hoc environments meets the “1 affects n” problem, which is more critical in such type of networks, due to the high dynamicity of groups. In this paper, we present an efficient clustering scheme for multicast key distribution in Mobile ad hoc networks. This scheme divides the multicast group into clusters, according to the localization of the group members and their mobility. Simulations indicate a valuable reduction in the average latency of keys distribution and a promising reduction in energy consumption. Analysis also shows that our scheme is scalable.

An enhanced hybrid key management protocol for secure multicast in ad hoc networks

An ad hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any established infrastructure or centralized administration. This flexibility in space and time induces new challenges towards the security infrastructure needed to support secure unicast and multicast communications. Especially, traditional group key management architectures meant for wired networks are not appropriate in such environment due to high dynamics and mobility of nodes.

Efficient Group Key Management Protocol in MANETs using the Multipoint Relaying Technique

In this paper, we present an efficient clustering scheme for application level multicast key distribution in mobile ad hoc networks. We show how our scheme can be combined with the Multipoint Relaying technique, in a very effective way, according to the localization of the group members and their mobility. The efficiency of this combination in terms of average latency of key delivery, energy consumption and key delivery ratio, is validated through simulation.

Formal verification of secure group communication protocols modelled in UML

The paper discusses an experience in using Unified Modelling Language and two complementary verification tools in the framework of SAFECAST, a project on secured group communication systems design. AVISPA enabled detecting and fixing security flaws. The TURTLE toolkit enabled saving development time by eliminating design solutions with inappropriate temporal parameters.

Automated verification of a key management architecture for hierarchical group protocols

Emerging applications require secure group communications involving hierarchical architecture protocols. Designing such secure hierarchical protocols is not straightforward, and their verification becomes a major issue in order to avoid any possible security attack and vulnerability. Several attempts have been made to deal with formal verification of group protocols, but to our knowledge, none of them did address the security of hierarchical ones. In this paper, we present the specific challenges and security issues of hierarchical secure group communications, and the work we did for their verification. We show how the AtSe back-end of the avispa tool was used to verify one of these protocols.RésuméDe nouvelles applications requièrent des communications de groupe, intégrant des protocoles hiérarchiques. La conception de ce genre de protocoles n’est pas aisée et leur vérification devient une véritable problématique pour éviter toute éventuelle attaque de sécurité. Plusieurs travaux de recherche se sont focalisés sur la vérification formelle des protocoles de groupe. Néanmoins, à notre connaissance, aucun d’eux n’a adressé les protocoles hiérarchiques. Ce papier présente les défis spécifiques et les problématiques de sécurité des communications de groupes hiérarchiques, ainsi que le travail effectué en vue de leur vérification. Nous montrons comment le back-end AtSe de l’outil de vérification des protocoles de sécurité avispa, a été utilisé pour valider l’un de ces protocoles.

Mobility-awareness in group key management protocols within MANETs

Several sensitive applications deployed within wireless networks require group communications. A high level of security is often required in such applications, like military or public security applications. The most suitable solution to ensure security in these services is the deployment of a group key management protocol, adapted to the characteristics ofManets, especially to mobility of nodes.In this paper, we present theOmct (Optimized Multicast Cluster Tree) algorithm for dynamic clustering of multicast group, that takes into account both nodes localization and mobility, and optimizes the energy and bandwidth consumptions. Then, we show how we integrateOmct within our group key management protocolBalade, in a sequential multi-source model. The integration ofBalade andOmct allows an efficient and fast key distribution process, validated through simulations, by applying various models of mobility (individual mobility and group mobility). The impact of the mobility model on the performance and the behaviour of the group key management protocolBalade coupled withOmct, is also evaluated.RésuméPlusieurs applications sensibles ciblées dans les réseaux ad hoc, requièrent des communications de groupe. Un niveau de sécurité élevé est souvent indispensable pour de telles applications, comme les applications de sécurité militaires ou publiques. La solution la plus appropriée pour assurer la sécurité de ces services est le déploiement d’un protocole de gestion de clé de groupe, qui doit être adapté aux caractéristiques desManets (Mobile Ad Hoc Networks), et notamment à la mobilité des noeuds.Dans cet article, nous présentons l’algorithmeOmct (Optimized Multicast Cluster Tree) de clusterisation dynamique du groupe multicast, tenant compte de la localisation et de la mobilité des noeuds, et optimisant la consommation de l’énergie et de la bande passante. Nous montrons commentOmct est intégré dans notre protocole de gestion de clésBalade, dans un cadre multi-sources séquentielles. Le couplage deBalade etOmct permet d’assurer une distribution de clés efficace et rapide, et est validé au travers de simulations, utilisant différents modèles de mobilité (mobilité individuelle et mobilité de groupe). L’impact du modèle de mobilité sur les performances et le comportement du couplageBalade etOmct, est aussi évalué