Hoang Lan Nguyen

Study of Different Types of Attacks on Multicast in Mobile Ad Hoc Networks

Security is an essential requirement in mobile ad hoc networks (MANETs). Compared to wired networks, MANETs are more vulnerable to security attacks due to the lack of a trusted centralized authority, easy eavesdropping, dynamic network topology, and limited resources. The security issue of MANETs in group communications is even more challenging because of the involvement of multiple senders and multiple receivers. In this paper, we present a simulationbased study of the impacts of different types of attacks on mesh-based multicast in MANETs. We consider the most common types of attacks, namely rushing attack, blackhole attack, neighbor attack and jellyfish attack. Specifically we study how the processing delay of legitimate nodes, the number of attackers and their positions affect the performance metrics of a multicast session such as packet delivery ratio, throughput, end-to-end delay, and delay jitter. To the best of our knowledge, this is the first paper that studies the vulnerability and the performance of multicast in MANETs under various security threats.

Bandwidth efficient multicast routing in multi-channel multi-radio wireless mesh networks

Multi-channel multi-radio (MCMR) wireless mesh networking is an emerging technology that enables high-throughput networking capability using multiple channels and multiple radios per mesh router. Traditional multicast routing algorithms such as shortest path trees and minimum Steiner trees do not consider the wireless broadcast advantage or the underlying channel assignments (i.e., channel diversity) in a MCMR wireless mesh network (WMN). In this paper, we propose a multicast routing algorithm for MCMR WMNs that takes into account the wireless broadcast advantage and channel diversity in order to minimize the amount of network bandwidth consumed by the routing tree. The algorithm does so by minimizing the number of transmissions required to deliver one packet from the source to all the destinations of a multicast group. Experimental results show that the proposed algorithm constructs routing trees having the least number of transmissions when compared with traditional trees such as shortest path trees, minimum Steiner trees, and minimum number of forwarders trees.

Minimum Interference Channel Assignment for Multicast in Multi-Radio Wireless Mesh Networks

Multi-radio, multi-channel wireless mesh networking is an emerging wireless technology which enables the use of multiple radios in each wireless mesh router. Each radio is assigned to a particular channel based on a channel assignment algorithm in order to solve some objective function, e.g., maximizing network throughput or minimizing wireless interference. Multicast is a form of communication that delivers information from a source to a set of destinations simultaneously. In this paper, we propose a channel assignment (CA) algorithm for multicast using both orthogonal and partially overlapping channels. The algorithm enables the nodes in a multicast tree to operate with minimum interference. We evaluate the performance of the proposed CA using various multicast group sizes and numbers of available channels, and compare it with that of the multi-channel multicast (MCM) algorithm proposed by Zeng et al. (2007).

Preemptive Multicast Routing in Mobile Ad-hoc Networks

Preemptive route maintenance allows a routing algorithm to maintain connectivity by preemptively switching to a path of higher quality when the quality of the currently used path is deemed questionable. Preemptive routing initiates recovery actions early by detecting that a link is likely to be broken soon and searching for a new path before the current path actually breaks. Preemptive route maintenance has been used for unicast (point-to-point) communications in wired networks and in mobile ad-hoc networks (MANETs) to minimize the number of route breaks and thus packet losses, and end-to-end delays. In addition to these advantages, we show that preemptive route maintenance can help minimize control overhead and improve the scalability of multicast routing protocols in MANETs. In this paper, we present design and implementation issues of preemptive routing for multicast in MANETs. We then describe a preemptive multicast routing protocol based on ODMRP (On-Demand Multicast Routing Protocol), which we call PMR (Preemptive Multicast Routing). PMR significantly improves the scalability of ODMRP: it offers similar or higher packet delivery ratios while incurring much less control overhead. Our simulation results have confirmed these advantages of PMR.

High-Performance Multicast Routing in Multi-Channel Multi-Radio Wireless Mesh Networks

Traditional multicast routing algorithms such as shortest path tree (SPT) and minimum Steiner tree (MST) do not consider the wireless broadcast advantage or the underlying channel assignments in a multi-channel multi-radio (MCMR) wireless mesh network (WMN). We propose a multicast routing algorithm for MCMR WMNs that takes into account the above factors in order to minimize the amount of network bandwidth consumed by a routing tree. Experimental results show that routing trees constructed by the proposed algorithm outperform traditional trees such as SPTs, MSTs and minimum number of forwarders trees (MFTs) with respect to packet delivery ratio, throughput and end-to-end delay.

A study of different types of attacks in mobile ad hoc networks

We present a simulation-based study of the impacts of different types of attacks in mobile ad hoc networks (MANETs). We consider three common types of attacks: blackhole attack, jellyfish attack and neighbor attack. Specifically, we study how the number of attackers and their positions affect the performance metrics of a connection such as packet delivery ratio, throughput, end-to-end delay, and delay jitter. The results enable us to suggest measures to minimize the impacts of the above types of attacks in MANETs.

Algorithms for bandwidth efficient multicast routing in multi-channel multi-radio wireless mesh networks

Traditional multicast routing algorithms such as shortest path tree (SPT) and Steiner tree (MST) do not consider the wireless broadcast advantage or the underlying channel assignments in a multi-channel multi-radio (MCMR) wireless mesh network (WMN). We propose multicast routing algorithms that take into account the above factors in order to minimize the amount of network bandwidth consumed by a routing tree. Experimental results show that routing trees constructed by the proposed algorithms outperform traditional trees such as SPTs, MSTs and minimum number of forwarders trees (MFTs) with respect to packet delivery ratio, throughput and end-to-end delay.

Data Overhead Impact of Multipath Routing for Multicast in Wireless Mesh Networks

Multipath routing has been proved effective in mobile ad-hoc networks (MANETs) for coping with link failures resulting from node mobility. In wireless mesh networks (WMNs) where routers are generally static, the traffic carried by the backup paths may adversely impact other flows and the multicast group itself, because these paths increase the number of transmissions and thus the level of interference and congestion in the network. This impact, however, has not been examined, especially for multicast routing. We present simulation results that quantify the impact of data overhead of multicast multipath routing compared with single-path routing.

Performance modeling of multicast with network coding in multi-channel multi-radio wireless mesh networks

Systems with multiple channels and multiple radios per node have been shown to enhance throughput of wireless mesh networks (WMNs). Recently, network coding has also been proved to be a promising technique for improving network throughput of WMNs. However, the performance of network coding in the context of multicast, a form of one-to-many communication, in multi-channel multi-radio (MCMR) WMNs is still unknown. In this paper, we present analytical models for estimating the average end-to-end delay, throughput and packet delivery ratio of a network-coded multicast session in 802.11-based MCMR WMNs. The proposed models are then validated using numerical analysis and simulations. To the best of our knowledge, our work is the first that studies the performance of network-coded multicast in MCMR WMNs.

Performance evaluation of network-coded multicast in multi-channel multi-radio wireless mesh networks

Systems with multiple channels and multiple radios per node have been shown to enhance throughput of wireless mesh networks (WMNs). Recently, network coding has also been proved to be a promising technique for improving network throughput of WMNs. However, the performance of network coding in the context of multicast in multi-channel multi-radio (MCMR) WMNs is still unknown. In this paper, we present a comprehensive performance evaluation of network-coded multicast in MCMR WMNs using extensive simulations, realistic network settings and meaningful performance metrics such as throughput, file completion time, packet end-to-end delay, and packet delivery ratio under a wide range of scenarios.