Maria Bennani

An efficient management algorithm for clustering in mobile ad hoc network

Clustering of mobile nodes among separate domains has been proposed as an efficient approach to mimic the operation of the fixed infrastructure and manage the resources in multi-hop networks. In this work, we propose a new clustering algorithm, namely Efficient Management Algorithm for Clustering (EMAC) based on weighting parameters. The goals are yielding low number of clusters, maintaining stable clusters, minimizing the number of invocations for the algorithm and maximizing lifetime of mobile nodes in the system. Through simulations we have compared the performance of our algorithm with that of WCA in terms of the number of clusters formed and number of states transitions on each clusterhead. The results demonstrate the superior performance of the proposed algorithm

A Flexible Weight Based Clustering Algorithm in Mobile Ad hoc Networks

Clustering has been proven to be a promising approach for mimicking the operation of the fixed infrastructure and managing the resources in multi-hop networks. In order to achieve good performance, the formation and maintenance procedure of clusters should operate with minimum overhead, allowing mobile nodes to join and leave without perturbing the membership of the cluster and preserving current cluster structure as much as possible. In this paper, we propose a Flexible Weight Based Clustering Algorithm (FWCA) in Mobile Ad hoc Networks. The goals are yielding low number of clusters, maintaining stable clusters, minimizing the number of invocations for the algorithm and maximizing lifetime of mobile nodes in the system. Through simulations we have compared the performance of our algorithm with that of WCA in terms of the number of clusters formed, number of re-affiliations, number of states transitions on each clusterhead and number of clusterheads changes. The results demonstrate the superior performance of the proposed algorithm.

Traffic aggregation based SIP over MPLS network architecture

The next generation communication system will provide high quality multimedia service in a more flexible and intelligent manner. In this paper, we propose a new SIP over MPLS network architecture to achieve this goal. To integrate SIP protocol with the traffic engineering (TE) function of MPLS network seamlessly and facilitate SIP call setup, the SIP-MPLS traffic aggregation server (TA server) is highlighted in this new architecture. Furthermore, the call admission and bandwidth renegotiation algorithms running on the TA server are investigated carefully. We rely on OPNET simulation to assess the performance of our network architecture and the capability of different call admission and bandwidth renegotiation algorithms. The simulation results show that the algorithm of TBCA-BP is a suitable candidate for accomplishing the call admission and bandwidth renegotiation task due to its satisfying performance, and our network architecture is able to shorten the SIP call setup delay greatly by using the TA server.

A practical proactive hybrid FEC/ARQ technique for reliable multi-session multicast communication

The application of FEC to multicast communication has seen significant developments recently. In this work, we have developed a new multi-session multicast QoS scheme using a hybrid proactive FEC/ARQ technique, and used a laboratory test-bed in order to evaluate this scheme. Our preliminary evaluation of hybrid proactive FEC/ARQ technique suggests shorter transmission time, decreased NAK traffic, and improved bandwidth utilization (reduced retransmission packets) when compared to the traditional ARQ reliable multicast technique.

Modeling and Simulation of Traffic Aggregation Based SIP over MPLS Network Architecture

In this paper, a traffic aggregation based SIP over MPLS network architecture is proposed to integrate SIP protocol with traffic engineering (TE) enabled MPLS network seamlessly and speed up the SIP call setup. We rely on OPNET simulation to assess the performance of this new network architecture. As a highlighted part, basic design concepts and implementation details of the simulation model are depicted intensively. The simulation results show that traffic aggregation based SIP over MPLS network architecture has satisfying performance in terms of SIP call setup delay, call blocking probability, and bandwidth utility efficiency.

SDL modeled hybrid error control scheme for reliable multicast over Internet

With the development of IP multicast and the Internet multicast backbone (Mbone), audio/video conferencing applications become more and more popular. These realtime multicast applications usually have stringent QoS requirements. As one of the most challenging tasks in the QoS guaranteed multicast network, the technology of controlling packet loss has attracted more and more attention. We introduce a new hybrid error control scheme that integrates interleaving, forward error correction (FEC), and threshold based automatic repeat request (threshold based ARQ) to mitigate the error and loss effects encountered in wire and wireless networks. In particular, the threshold based ARQ is studied carefully to shorten the transmission delay in reliable multicast. Moreover, in order to simplify the description and validation of our scheme, specification and description language (SDL) is used for modeling it. SDL depicts different levels of our scheme, from a broad overview down to detailed designs. After the basic algorithms of hybrid error control are devised, the corresponding implementations are developed to achieve the practical performance of our scheme, and the experimental results are analyzed.

Bandwidth fragmentation avoided QoS multicast routing by employing admission control

The rapid growth of multimedia group-based applications motivates research into QoS guaranteed multicast network. In the multicast network carrying traffics of different QoS requirements, bandwidth fragmentation is considered as a bottleneck for traffic admission fairness and efficient usage of bandwidth resource. When the bandwidth fragmentation happens, the chance of accepting high-bandwidth flows is greatly decreased. To prevent bandwidth fragmentation in multicast network, we propose a new approach of bandwidth fragmentation avoided QoS multicast routing in this paper. In our new approach, we integrate active admission control into traditional QoS multicast routing algorithms to gain bandwidth fragmentation immunity. Moreover, an algorithm named dynamic bandwidth allocation with adaptive constraint is proposed and investigated as an example of active admission control algorithm in this paper. Because this algorithm is nonlinear and unsolvable by analytical approach, we employ OPNET simulation to study its performance.

Interleaved FEC/ARQ coding for QoS multicast over the internet

The technology of real-time reliable multicast over a best-effort service network has become more popular recently. In this paper, a new technique is introduced that integrates word interleaving, forward error correction (FEC) and automatic repeat request (ARQ) to mitigate the error and loss effects encountered in wired and wireless Internet applications. For multicast video sessions spanning tens of routers, the integration of interleaving, FEC and ARQ as well as fine tuning of the various parameters of each mechanism will play a major role in the move towards successful deployment. In this work, the basic algorithms for integrated error control are first derived. Then the corresponding real-time implementations for an experimental testbed to achieve the practical performance of these techniques are completed. The performance of the scheme is analyzed, and laboratory results are compared with analytical results.

Dynamic Bandwidth Allocation in SIP based MPLS

With the migration of real-time applications such as voice onto IP-based platforms, the existing IP network capabilities become inadequate to provide the quality-of- service (QoS) levels that the end-users are accustomed to. While new protocols such as DiffServ and MPLS allow some amount of traffic prioritization, guaranteed QoS requires admission control and dynamic resource management. Over-reservation has the advantage of infrequent variations but leads to wastage of resources. Under- reservation, on the other hand, does not meet the QoS expectations of the user flows. In this paper, we consider the architecture based on SIP (Session Initiation Protocol) over MPLS to provide control admission. In this architecture, we propose a new method to reserve optimally the bandwidth of an LSP (Label Switched Path), avoiding an excess of bandwidth renegotiations on the basis of prediction of future traffic.

Integrating traffic aggregation mechanism into SIP based IP telephony over MPLS network

In order to provide high quality multimedia service in a flexible and intelligent manner, future wired and wireless networks will employ SIP as the call control protocol and MPLS as the core network packet switching technology. In this paper, we propose a traffic aggregation based SIP over MPLS network architecture to integrate SIP protocol with the traffic engineering (TE) function of MPLS network seamlessly. Furthermore, the call admission and bandwidth prediction/re-negotiation algorithms running in this new network architecture are investigated intensively. We rely on OPNET simulation to assess the performance of different call admission and bandwidth prediction/re-negotiation algorithms. The simulation results show that the algorithm of FCFS-LMS-BPR is an eligible candidate for achieving the designated goals.