A distributed key establishment scheme for wireless mesh networks using identity-based cryptography

In this paper, we propose a secure and efficient key establishment scheme designed with respect to the unique requirements of Wireless Mesh Networks. Our security model is based on Identity-based key establishment scheme without the utilization of a trusted authority for private key operations. Rather, this task is performed by a collaboration of users; a threshold number of users come together in a coalition so that they generate the private key. We performed simulative performance evaluation in order to show the effect of both the network size and the threshold value. Results show a tradeoff between resiliency and efficiency: increasing the threshold value or the number of mesh nodes also increases the resiliency but negatively effects the efficiency. For threshold values smaller than 8 and for number of mesh nodes in between 40 and 100, at least 90% of the mesh nodes can compute their private keys within at most 70 seconds. On the other hand, at threshold value 8, an increase in the number of mesh nodes from 40 to 100 results in 25% increase in the rate of successful private key generations

Impact Analysis of Wormhole and Blackhole attacks over Mobile Ad Hoc Networks

In this paper, we will implement two attacks over mobile ad hoc networks known as Wormhole attack and Blackhole attack. We will also analyze the impact of these attacks on data communication when using a reactive routing protocol for data communication. The reactive routing protocol used is well known Ad-hoc On- demand Distance Vector (AODV) protocol. In the Wormhole attack, at least two malicious nodes i.e., attackers disseminates wrong network information to its neighbors during the routing table formation due to which these attacks become the intermediate nodes on the selected route and drop data packets during the communication process. These two attackers form a tunnel through which they can sent the control packets to each other and if one of them are is placed near the destination then they can make sure that they are being selected on the discovered path. Due to the wrong information spread by the malicious nodes the routing tables of its nearby nodes contains untrue information about routes to various or specific destinations. When this wrong information is used for data communication during the communication process the all the data packets will go to wrong nodes and eventually dropped by attacker nodes. This decreases the network throughput and packet delivery ratio while wastes the scarce network bandwidth. On the other hand, in blackhole attack the attacker node comes on the discovered route and drop all the packets received for destination. To implement the proposed attacks, we used a network simulator called Exata simulator. The simulation results are collected for performance analysis of the underlying network. Various metrics such as packet delivery ratio and network throughput are used to show the effect of the proposed attack over a wide range of network scenarios

Routing in mobile Ad Hoc Networks

A Mobile Ad Hoc Network (MANET) is built on the fly where a number of wireless mobile nodes work in cooperation without the engagement of any centralized access point or any fixed infrastructure. Two nodes in such a network can communicate in a bidirectional manner if and only if the distance between them is at most the minimum of their transmission ranges. When a node wants to communicate with a node outside its transmission range, a multihop routing strategy is used which involves some intermediate nodes. Because of the movements of nodes, there is a constant possibility of topology change in MANET. Considering this unique aspect of MANET, a number of routing protocols have been proposed so far. This chapter gives an overview of the past, current, and future research areas for routing in MANET. In this chapter we will learn about the following things: - The preliminaries of mobile ad hoc network - The challenges for routing in MANET - Expected properties of a MANET routing protocol - Categories of routing protocols for MANET - Major routing protocols for MANET - Criteria for performance comparison of the routing protocols for MANET - Achievements and future research directions - Expectations and realit

Supplementing an AD-HOC Wireless Network Routing Protocol with Radio Frequency Identification (RFID) Tags

Wireless sensor networks (WSNs) have a broad and varied range of applications, yet all of these are limited by the resources available to the sensor nodes that make up the WSN. The most significant resource is energy. A WSN may be deployed to an inhospitable or unreachable area, leaving it with a non-replenishable power source. This research examines a way of reducing energy consumption by augmenting the nodes with radio frequency identification (RFID) tags that contain routing information. It was expected that RFID tags would reduce the network throughput, the ad hoc on-demand distance vector (AODV) routing traffic sent, and the amount of energy consumed. However, the results show that RFID tags have little effect on the network throughput or the AODV routing traffic sent. They also increase ETE delays in sparse networks as well as the amount of energy consumed in both sparse and dense networks. Furthermore, there was no statistical difference in the amount of user data throughput received. The density of the network is shown to have an effect on the variation of the data but the trends are the same for both sparse and dense networks. This counter-intuitive result is explained, and conditions for such a scheme to be effective are discussed

Verifying Route Request Procedure of AODV Using Graph Theory and Formal Methods

Guta Moura Guedes vai comissariar o primeiro núcleo de programação de La Gaité, o novo equipamento cultural de Paris.Com abertura ao público marcada para Dezembro de 2010, La Gaité é o novo equipamento cultural de Paris dedicado à cultura contemporânea com especial foco nas áreas da criação digital e das novas tecnologias, cruzando música, vídeo, design, cinema, arquitectura e arte. A programação deste novo espaço parisiense dedicado à cultura, tranversal e dinâmico, inicia-se em 2011 com tr..

On the performance of probabilistic flooding in wireless mobile ad hoc networks

Broadcasting in MANET’s has traditionally been based on flooding, but this can induce broadcast storms that severely degrade network performance due to redundant retransmission, collision and contention. Probabilistic flooding, where a node rebroadcasts a newly arrived one-to-all packet with some probability, p, was an early suggestion to reduce the broadcast storm problem. The first part of this thesis investigates the effects on the performance of probabilistic flooding of a number of important MANET parameters, including node speed, traffic load and node density. It transpires that these parameters have a critical impact both on reachability and on the number of so-called “saved rebroadcast packets” achieved. For instance, across a range of rebroadcast probability values, as network density increases from 25 to 100 nodes, reachability achieved by probabilistic flooding increases from 85% to 100%. Moreover, as node speed increases from 2 to 20 m/sec, reachability increases from 90% to 100%. The second part of this thesis proposes two new probabilistic algorithms that dynamically adjust the rebroadcasting probability contingent on node distribution using only one-hop neighbourhood information, without requiring any assistance of distance measurements or location-determination devices. The performance of the new algorithm is assessed and compared to blind flooding as well as the fixed probabilistic approach. It is demonstrated that the new algorithms have superior performance characteristics in terms of both reachability and saved rebroadcasts. For instance, the suggested algorithms can improve saved rebroadcasts by up to 70% and 47% compared to blind and fixed probabilistic flooding, respectively, even under conditions of high node mobility and high network density without degrading reachability. The final part of the thesis assesses the impact of probabilistic flooding on the performance of routing protocols in MANETs. Our performance results indicate that using our new probabilistic flooding algorithms during route discovery enables AODV to achieve a higher delivery ratio of data packets while keeping a lower routing overhead compared to using blind and fixed probabilistic flooding. For instance, the packet delivery ratio using our algorithm is improved by up to 19% and 12% compared to using blind and fixed probabilistic flooding, respectively. This performance advantage is achieved with a routing overhead that is lower by up to 28% and 19% than in fixed probabilistic and blind flooding, respectively

Watchdogs colaborativos para la detección de nodos maliciosos en redes MANET

En esta Tesis de Master se ha trabajado en la detección de nodos maliciosos que pudieran estar presentes en redes móviles ad-hoc (MANETs), utilizando watchdogs en los nodos que las forman, de tal manera que dichos watchdogs colaboran entre ellos para mejorar la rapidez y exactitud de la detección.Serrat Olmos, MD. (2011). Watchdogs colaborativos para la detección de nodos maliciosos en redes MANET. http://hdl.handle.net/10251/15673Archivo delegad