Self-organized classification of dangers for secure Wireless Mesh Networks

Wireless technology is emerging as a key technology for the future networks. Wireless mesh networks (WMNs) have emerged as an indispensable technology for deployment of wireless services for various applications in personal, enterprise, and metropolitan areas. Researchers are working actively in different fields of WMNs for providing better services. Routing protocols play a vital role in WMNs to provide reliable configuration and maintenance of topology of the network. Designing a suitable cost metric for routing protocols to provide quality links for data transmission is the backbone of WMNs. Many cost metrics have been proposed for WMNs and is still an active research topic as new performance metrics need to be discovered due to the dynamics of this field. This paper considers the genetic algorithm-based routing technique for WMN.We have studied the existing cost metrics and proposed a genetic algorithm technique for routing in WMN. To evaluate the genetic algorithm, and to determine the relative performance of the genetic algorithm in the context of routing in WMN, we carry out experiments on two test systems. We have evaluated the quality of the results produced by our algorithm with the traditional hop count metric results. Our results show that routing in WMN using genetic algorithm produces better results as compared to traditional hop count metric results. Finally, we carry out a detailed analysis of results, which help us in gaining an insight into the suitability of genetic algorithm for routing in WMN.

Multi-hop Wireless Mesh Networks (WMNs) is a promising new technique for communication with routing protocol designs being critical to the effective and efficient of these WMNs. A common approach for routing traffic in these networks is to select a minimal distance from the source to destination as in wireless networks. Opportunistic Routing (OR) makes use of the broadcasting ability of wireless network and is especially very helpful for WMN because all nodes are static. Our proposed scheme of Multicast Opportunistic Routing (MOR) in WMNs is based on the broadcast transmissions and Learning Automata (LA) to expand the potential candidate nodes that can aid in the process of retransmission of the data. The receivers are required to be in sync with one another in order to avoid duplicated broadcasting of data which is generally achieved by formulating the forwarding candidates according to some LA based metric. The most helpful aspect of this protocol is that it intelligently learns from the past experience and improves its performance. The results obtained via this approach of MOR show that the proposed scheme outperforms some existing schemes and is an improved and more effective version of opportunistic routing in a mesh network.

Finding the shortest route in wireless mesh networks is an important aspect. Many techniques are used to solve this problem like dynamic programming, evolutionary algorithms, weighted-sum techniques, and others. In this paper, we use dynamic programming techniques to find the shortest path in wireless mesh networks due to their generality, reduction of complexity and facilitation of numerical computation, simplicity in incorporating constraints, and their onformity to the stochastic nature of some problems. The routing problem is a multi-objective optimization problem with some constraints such as path capacity and end-to-end delay. Single-constraint routing problems and solutions using Dijkstra, Bellman-Ford, and Floyd-Warshall algorithms are proposed in this work with a discussion on the difference between them. These algorithms find the shortest route through finding the optimal rate between two nodes in the wireless networks but with bounded end-to-end delay. The Dijkstra-based algorithm is especially favorable in terms of processing time. We also present a comparison between our proposed single-constraint Dijkstra-based routing algorithm and the mesh routing algorithm (MRA) existing in the literature to clarify the merits of the former.

Intrusion Detection Systems(IDSs) are widely used to detect both known attacks and unknown attacks performed by internal and external attackers in wireless networks. However, challenging issues for developing IDSs in Wireless Mesh Networks (WMNs) are 1) supporting interoperability and 2) handling volatile parameters. In addition, security standards for WMN are still in draft stage, and to protect the WMN, IDSs of similar wireless networks such as wireless sensor, Ad-Hoc, MANET can be adopted, but the best performance is not guaranteed. In this paper, we have classified the existing IDSs for wireless networks into four categories namely single layer IDS, cross-layer IDS, reputation-based IDS, reputation based cross-layer IDS, and analyzed the performance of these IDSs with core-layer attacks and detection methodology. Based on our analysis, we address the loopholes in existing IDSs and specify research directions for strengthening the existing IDSs and for developing new efficient IDSs with respect to backbone mesh and client mesh networks.

QoS routing problem in wireless mesh networks is a NP-complete problem, and it is hard to get the global solution with the traditional algorithm. In this paper, we adopt a novel dynamic ant genetic hybrid algorithm to solve QoS unicast routing problem for wireless mesh network, whose innovation are using the best melting point evaluation strategy to control the calling of the two algorithms dynamically. Simulation results show that the novel algorithm is superior to the genetic algorithm and the static ant genetic hybrid algorithm in quality and efficiency for QoS routing in wireless mesh network.

Interference makes it difficult for a wireless network to provide robust performance and could sometimes lead to transient failures. Dynamic channel switching (DCS) allows a wireless network interface (NIC) to operate in different frequency channels during different time periods without disrupting network connections that traverse the NIC. DCS enables a wireless mesh network to avoid frequency channels with serious interference in certain parts of its coverage area by switching to more idle channels. Although DCS provides additional radio agility, it significantly increases the complexity of the wireless mesh network's routing protocol. This paper describes the design, implementation and evaluation of a wireless mesh network system called Carlsbad, which supports both DCS and load-balancing/fault-tolerant routing, and successfully runs on low-cost commodity IEEE 802.11-based access points. Performance experiments on the first Carlsbad prototype show that despite the additional overhead it introduces, DCS can indeed improve the overall throughput of an IEEE 802.11-based wireless mesh network, sometimes by a factor of more than 2, for both TCP and UDP connections.

The popularity and the constant improvement of wireless technologies, such as WiFi and WiMAX, have been increasing the usage and applicability of new networking schemes, including Wireless Mesh Networks (WMNs). WMNs are multi-hop wireless networks made by a collection of two types of nodes, mesh routers and mesh clients. Their self-organizing, self-configuring and self-healing proprieties, in conjunction with their low maintenance and implementation costs, make them especially appealing as a solution for Internet access and social networking. The characteristics of WMNs make them more susceptible to malicious attacks than traditional wired networks, namely the scarce bandwidth, the high level of interference, the shared transmission media and the limited physical security. Secure routing and forwarding schemes are a key component to guarantee secure communications in hostile environments. There are however issues that must be considered when developing secure routing and forwarding solutions, namely the overhead introduced by such approaches and the effectiveness of the prediction schemes used. This paper discusses the main solutions for routing security in WMNs and presents a thorough evaluation, comprising a novel way to characterize the effectiveness of such approaches. The evaluation is based on CONFIDANT, a secure routing protocol based on the DSR protocol. The study performed addresses both the issues aforementioned and provides insight on the trade-offs associated with the deployment of secure routing and forwarding mechanisms.

In recent years, mesh networking has emerged as a key technology for the last mile Internet access and found to be an important area of research and deployment. The current draft standard of IEEE 802.11s has defined routing for Wireless Mesh Networks (WMNs) in layer-2 and is termed as Hybrid Wireless Mesh Protocol (HWMP). However, security in routing or forwarding functionality is not specified in the standard. As a consequence, HWMP in its current from is vulnerable to various types of routing attacks such as flooding, route disruption and diversion, spoofing etc. In this paper, we propose a secure HWMP routing protocol for WMN. The proposed protocol uses cryptographic extensions to provide authenticity and integrity of HWMP routing messages and prevents unauthorized manipulation of mutable fields in the routing information elements. We will show that the proposed protocol successfully thwarts all the identified attacks.

Wireless mesh networks (WMN) are believed to be a highly promising technology and will play an increasingly important role in future generation wireless mobile networks. Routing in WMN is a challenging problem as a result of highly dynamic topology as well as bandwidth and energy constraints. The swarm intelligence paradigm, such as ant colony optimization (ACO), has recently been demonstrated as an active approach for routing in both wired and wireless networks. We designed a novel ACO-based multicasting routing algorithm. In the proposed algorithm, a source-based approach is adapted to build a multicast tree among all the multicast members, and an evolutional scheme for the original multicast tree is designed to find a more optimal multicast tree. In addition the evolutional scheme also acts as a local recovery technique when some intermediate nodes move away. Compared with ODMRP and MAODV, the proposed algorithm performs better in terms of average delay, success ratio and efficiency.

QoS routing in wireless mesh networks (WMNs) is a daunting task. Finding a path for a given flow depends not only on the bandwidth-delay requirements of that flow but also on the available bandwidth of all the nodes in that path and the amount of bandwidth consumption caused by that flow along its path. Contrary to the wired networks, these two parameters are not fixed and depend on the interference pattern of the network that in turn depends on the selected path itself. This converts the QoS routing in wireless mesh networks to a much harder problem. Existing methods use on-demand approach based on flooding of routing packets. This approach does not scale up to large networks. Field-based routing (FBR) is a promising approach to reduce the routing overhead for static route set up. However, it is not previously used for QoS routing. In this paper, we have developed a new FBR based QoS routing protocol for WMNs. Contribution of this paper is two folds. First, a one-pass field-based routing instead of regular two-pass approach is developed that significantly reduces the overhead of distributing routing information and computing the path and increases the QoS delivered to the flows. Secondly, a new routing metric named LU-IR is introduced that is shown to lower intra-flow and inter-flow interferences and results in increased network service capacity. The performance of the proposed algorithm is extensively studied through simulations. The results indicate that average delay of the flows is improved and the network throughput is increased compared to the existing schemes.

The ultimate goal of routing in wireless mesh networks (WMNs) is to find the “good” paths between the source and destination. Considering of the characteristics of this new networking paradigm, such as low mobility and less restriction from the energy effect, the focus is on the design and optimization of the technology to establish the path that can reflect this network feature. In this paper, an efficient routing algorithm is proposed based on decision-making sequence in WMNs, and the routing process is mapped into multi-stage decision process. We construct a mathematical model for it and present a multi-decision sequential routing method taking use of the idea of dynamic programming. In addition, a new metric (EEDT) for routing based on the information of MAC layer in WMNs is given, which optimized the two objectives- end to end delay and throughput. In the end, the multi-decision sequential routing algorithm (MDSR) is proposed that synthesized the suggesting method and new metric. The path selected by MDSR would be better based on the mathematical model, and it has lower delay of routing building. At the same time, EEDT can accurately capture the quality of the network links. Simulation results show that the proposed routing algorithm significantly improves the performance of the WMNs in terms of end-to-end delay and throughput.

Wireless technology has become an essential part of this era’s human life and has the capability of connecting virtually to any place within the universe. A mesh network is a self healing wireless network, built through a number of distributed and redundant nodes to support variety of applications and provide reliability. Similarly, anycasting is an important service that might be used for a variety of applications. In this paper we have studied anycast routing in the wireless mesh networks and the anycast traffic from the gateway to the mesh network having multiple anycast groups. We have also studied the geocast traffic in which the packets reach to the group head via unicast traffic and then are broadcasted inside the group. Moreover, we have studied the intergroup communication between different anycast groups. The review of the related literature shows that no one has considered anycasting and geocasting from gateway to the mesh network while considering the multiple anycast groups and intergroup communication. The network is modeled, simulated and analyzed for its various parameters using OMNET++ simulator.

Efficient multicasting over Wireless Mesh Network (WMN) is challenging due to dynamic and multi-hop wireless communication among multicast group members. Multicast Ad hoc On-Demand Distance Vector (MAODV) protocol is a tree based multicast routing protocol that enables dynamic, self-starting, multi-hop routing between participating mobile nodes wishing to join or participate in a multicast group in Wireless Mesh Network (WMN). The mobility of mobile nodes often causes link breakage in the tree-based protocols which sometime results in tree partitioning and poor performance. In MAODV, when a broken link is detected between two nodes on the multicast tree, the node downstream to the break is responsible for initiating the repair of the broken link. After link repair, it is likely that the previous distance between the nodes (nodes downstream to the link breakage) and the group leader will not remain same. The shortest path from the group leader to the nodes downstream to the node which initiates link breakage is not ensured. Moreover, if the node attempting to repair a tree link break does not receive a response after certain attempts, it assumes that the multicast tree is not repairable currently and this leads to tree partitioning. In this paper, an improved link repair technique is proposed which ensures shortest path from any node to the group leader. Simulation results demonstrate significant improvement in performance metrics compared to standard MAODV.

To support reliable multicast routing in wireless mesh networks, it is important to protect multicast sessions against link or node failures. The issue of protecting multicast sessions in wireless mesh networks is a new problem to the best of our knowledge. In this paper, we propose a resilient forwarding mesh approach for protecting a multicast session in wireless mesh networks. Utilizing the wireless broadcast advantage, a resilient forwarding mesh effectively establishes two node disjoint paths for each source-destination pair. This allows a multicast session to be immune from any single link or intermediate node failure. We introduce four heuristic algorithms to obtain approximate solutions that seek to minimize the number of required broadcast transmissions. We evaluate the performance of these heuristic algorithms against the optimal resilient forwarding mesh (ORFM) obtained by solving an integer linear programming (ILP) formulation of the problem. Experimental results demonstrate that one of these heuristic algorithms, which we call the minimal disjoint mesh algorithm (MDM), performs sufficiently close to ORFM. Besides, we find that the resilient forwarding mesh approach provides efficient 1+ 1 protection (Pioro and Medhi, 2004) to the multicast session without incurring much additional overhead on a single minimal cost multicast tree

Routing is a critical component in wireless mesh networks. The inherent shared-medium nature of the wireless mesh networks, however, poses fundamental challenges to the design of effective routing policies that are optimal with respect to the resource utilization. Node churns and traffic fluctuations exacerbate such a problem. In this paper, we propose a novel adaptive routing algorithm for multiple subscribers in wireless mesh networks. We view a mesh network with multiple nodes as an entity that optimizes some global utility function constrained by the underlying MAC layer interference. By solving the optimization problem, the network is driven to an efficient operating point with a certain routing policies for each node. We then use this operating point information to adaptively find better paths, which is able to gear the network towards optimal routing. Further, we take the fluctuations of the network into consideration and thus render our algorithm more robust for a variety of network situations. Simulations demonstrate the efficiency and efficacy of our algorithm.