Efficient algorithm and study of QoS-aware mobile Ad hoc network methods

Mobile ad hoc networks (MANETs) are consists of mobile devices connected wirelessly. Mobile nodes in MANET are applicable of routing functionality, where messages are forwarded in a multi-hop fashion. In such a communication scheme a routing protocol play an important role in the network performances. The wireless connectivity and node mobility in MANET networks contributes in rapid topological changes, which brings the need for a channel aware routing protocol. To overcome this problem, many channel aware routing metrics are proposed in the literature, however these routing metrics are either utilizing the shared bandwidth to measure the link quality, or they implies less awareness to the link quality. This paper proposed a SNR-based routing metric for Dynamic Sequence Distance Vector (DSDV) routing protocol. This paper starts by investigate and compare the performance among common routing protocols in MANET. Secondly a cross layer approach is proposed for the new routing metric. Simulation scenarios are used for the work of the paper. The new metrics is implemented in one of the MANET common routing protocols DSDV module in MONET++. The results show that SNR-based DSVD improves the performance of the MANET in terms of throughput and delay.

Background:AMobileAdHocNetwork (MANET) consistsofmany independentnodes that operate over awireless topology with numerous Quality of Service (QoS) requirements. So, a robust routing protocol that also provides QoS parameters to its different range of applications is needed. Various network parameters like node density, node mobility, field size etc. also effects the QoS parameters of MANETs. Methods: The traditional reactive routing protocols do not have any backup route in case of a node failure and hence are not effective for MANETs. Ad Hoc on Demand Distance Vector Backup Routing (AODV BR) protocol performs better than traditional routing protocols but is not effective when the backup route fails. So, to counter this problem, the authors had proposed AODV nth BR that keeps on providing backup routes when multiple nodes fail and hence successfully transfers the data to the destination. The nodes for backup routing are selected based on their distance from the failed node and energy efficiency. Results: In this paper, the performance of AODV nth BR has been compared with AODV, DSR and AODV BR protocol under varying node density (nodes 20, 60,100) and node mobility conditions (5m/s, 20m/s, 50m/s). The values for Packet Delivery Fraction (PDF) for 60 nodes at speed 20m/s in case of AODV nth BR protocol after 6000 rounds is 0.3054. Comparatively, value of AODV BR is 0.2664, AODV is 0.1936 and DSR is 0.1056. QoS performance is measured in terms of end to end delay, packet delivery fraction and lifetime of devices and it has been shown through simulated results that AODV nth BR protocol gives better output than traditional routing protocols. Conclusion: From the simulated results explained in detail in the paper, it has been observed that route after link breakage is found to be best with AODV nth BR protocol and this can be clearly seen in the QoS parameters obtained.Keywords: AODV BR, AODV nth BR, MANETs, Node Density, Node Mobility

SUMMARYA mobile ad hoc network (MANET) is an open wireless network that comprises a set of mobile, decentralized, and self‐organized nodes. Its properties render its environment susceptible to different types of attacks, which can paralyze the mobile nodes in MANET. A particularly dangerous type of attack is run primarily under flooding bogus packet mechanisms, such as hello floods, routing table overflows, exploitation of node penalizing schemes, and resource consumption attack (RCA). Flooding‐based attacks impose severe effects because they are intended to consume MANET resources, such as bandwidth, node memory, and battery power. Therefore, identifying such effects facilitates the development of countermeasures against the intrusions. In this paper, we introduce a simulation‐based study on the effects of RCA on MANET. QualNet v5.0.2 is used to examine the severity of the effects on MANET performance metrics in terms of throughput, end‐to‐end delay, energy consumption, and routing overhead. The effects of RCA are also monitored under two combinations of four factors: we first vary the number of attackers and attackers' positions, and then modify the attackers' radio range and flooding rate. We also examine the effect of flooding mechanism on the energy consumed by resource consumption attackers. Copyright © 2013 John Wiley & Sons, Ltd.

With the evolution of dynamically changing network applications, for efficient, seamless and last mile connectivity Mobile Ad-hoc Networks (MANETs) provide a cost effective solution. The mobile nodes in MANETs are randomly connected and their location and functioning keeps on changing based on the situation and network application requirement. However, the nodes in MANETs are battery powered which is one of the limiting factors in their performance. However, seamless and longer duration connectivity depends upon the lifetime of individual nodes. The power consumption during transmission is the critical design issue in MANET's. This work involves the performance evaluation of a designed MANET scenario with variation in transmission power using Ad-hoc On-Demand Multipath Distance Vector (AOMDV) Routing Protocol (RP) at variable node configuration. The performance of designed MANET scenario is evaluated using several qualitative performance metrics for optimum performance using QualNet simulator.

Mobile Ad hoc network (MANET) is a short range network which enables various mobile nodes to communicate with each other. The range of mobile node for communication is limited in the MANET so two nodes of different network which are placed in long distance are unable to communicate between them. Utility of MANET can be enhanced by providing Internet connectivity to the mobile nodes. MANET is infrastructureless and Internet is infrastructure type network so they require an interface to connect with each other. So in this situation, Gateway, a device which acts as an interface and a router, provides the MANET nodes connectivity to fixed networks. A mobile node in MANET has to find a route to a gateway first to communicate with the Internet host. It requires an efficient gateway discovery mechanism for improve the overall performance of network. For this process various approaches have been proposed in the past. The popular approaches are reactive, proactive and hybrid gateway discovery mechanisms. This paper focuses on various issues for MANET-Internet integration and their proposed technical solutions by various proposals for different Internet gateway discovery mechanisms to improve the performance.

A Mobile Ad Hoc Network (MANET) is one of the up-to-date technologies supporting communication of mobile devices. It consists of an open environment that comprises a set of mobile, decentralized, and self-organized nodes. MANET is harder to be secured than the other types of static networks. There are many types of attacks that could paralyze the life of the mobile nodes in MANET. One of the most dangerous attacks is the Denial of Service attack (DoS), which in turn could be performed through the Resource Consumption Attack (RCA) over Ad-hoc On demand Distance Vector (AODV) routing protocol. This paper analyzes and studies the RCA effecting factors on AODV performance metrics namely throughput and end-to-end delay under varying the number of connections between the source and the destination and number of RCA attackers number.Keywords: MANET, Resource Consumption Attack, Denial of Service attack, AODV routing protocol.

Mobile Ad hoc Networks (MANET) comprises of self-organizing autonomous mobile nodes. MANETs are open and decentralized. Therefore they are vulnerable to malicious entities. MANETs are multi-hop wireless network where all nodes supportively maintain network connectivity without a centralized infrastructure. Since MANETs are infrastructure less and independent, the secure communication is the main issue. Therefore they are vulnerable to malicious entities. Here the location identity and traffic can be traced out by an outside observer. Anonymity means secure communications by hiding node identities and preventing traffic analysis attacks by outside observers. This paper proposes Position based Anonymous Routing Scheme in MANETs (PARS).Here the routing is based on Greedy Perimeter Stateless Routing Protocol. The objective is an anonymous routing protocol for the network. The proposed one is a zone based anonymous GPSR based protocol that can provide source, destination and route anonymity. Performance of the proposed system is compared with that of GPSR and AODV using Network Simulator. Index Terms: Anonymous routing, position-based routing, random forwarder, zone partition. I. Introduction Mobile Ad hoc Networks are collection of independent mobile nodes that can communicate by radio waves. It is an infrastructure less self-organizing network. The nodes that are in radio range can communicate by single hop or by multi hop with the help of intermediate nodes. The network is open and decentralized and fully distributed. So they are perfect choice for communication and information sharing. MANETs are susceptible to malicious entities that aim to alter and analyzed the traffic analysis by communication eaves dropping or attacking routing protocols. MANETs are characterized by their distributed operation, multi hop routing, dynamic topology and shared physical medium. Nodes in a MANET are independently free to move in any direction. Due to the lack of a centralized coordinator security is the major concern here. Wireless communication can endure interferences or malicious interceptions; whereas multi-hop communication assumes that each node will perform properly its functions to support network services. Further, self-organization increases the complexity of security management operations as access control, node authentication, secure routing and cryptographic key distribution. There is no fixed infrastructure and the topology is frequently changing due to node mobility or environmental changes. Therefore, it is very hard to maintain a stable and efficient end-to-end route in an ad-hoc network. Each node in MANET is energy constrained. There is verylimited physical security in MANET. The type of attacks can be Active attacks or Passive attacks. The common security issues are Passive attacks which include eaves dropping and information disclosure. Active attacks include Do Sand Data modification. There are other more specific problems with mobile ad hoc network such as vulnerability of channels and nodes, Byzantine black hole and Byzantine wormhole attack. The security issue also includes attacks that may inject erroneous routing information and diverting network traffic thus making routing inefficient. There are many methods to reduce the impact of these attacks, which include a secure routing using public and private key s to get a certification authority and use of digital signatures and prior it rust relationships. Routing is the process of communication from one node to the other host in a network. Routing is the process off or warding packet towards its destination using most efficient path. Routing efficiency is measured in terms of Number of hops, traffic, security, etc. Routing protocols in MANETs are divided as reactive proactive and hybrid. Reactive Protocol maintains the routes in on demand manner. In route discovery phase it floods the route request (RREQ) packets throughout the network. Dynamic source Routing (DSR), ad hoc on- demand distance vector routing (AODV) are some of the examples of reactive protocols. In proactive approach every node in the MANET continuously maintains the complete routing information of the entire network. This is accomplished by flooding network periodically with network status information. Global State Routing (GSR), Hierarchical State Routing (HSR) and Destination Sequenced Distance Vector Routing (DSDV) are some of the examples of proactive

Trust management in mobile ad hoc networks for bias minimization and application performance maximization

OLSR is a proactive routing protocol for mobile ad hoc networks (MANETs). OLSR uses a concept of MPR selection mechanism to reduce broadcast packets during a flooding process. MPR nodes use more energy than nonMPR nodes. Thus they easily run out their energy since mobile nodes in MANETs are powered by battery with limited energy. This paper proposes a residual energy-based OLSR protocol named REOLSR2. The REOLSR2 selects MPR nodes based on not only reachability and degree but also residual energy of 1-hop neighbors. The aim is to avoid selecting MPR nodes which has small residual energy and concentrating energy consumption in specific nodes. Simulation results show that the proposed scheme reduces energy consumption and enhances network throughput efficiently.

Using location information to help routing is often proposed as a means to achieve scalability in large mobile ad hoc networks(MANETs). One of the biggest challenge in geographic routing protocols is the design of scalable distributed location services that can locate the positions of mobile nodes. The accurate positioning of mobile nodes in MANETs is important to location service scheme since they are related to efficiency of routing protocols. We propose a grid-based predictive Location Service(GPLS) scheme. In proposed location service scheme GPLS, the network is partitioned into grids and grids are divided into groups by using a HASH function, which guarantees the uniform distribution of location servers of a node in the network. The proposed location service scheme GPLS provide accurate location query capability by means of location prediction of mobile nodes. The simulation results show that the location service scheme GPLS have better performance than CRLS and SLURP in query success ratio, query delay.

The mobility and resource limitation of nodes are the critical factors that affect the performance of Mobile AD hoc network (MANET). The mobility of nodes will affect the stability of links, and the limitation of node resources will lead to congestion, so it is very difficult to design a routing protocol that supports quality of service (QoS) in MANET. Especially in the scenario of high-speed node movement, frequent link interruption will damages QoS performance, so it is necessary to design MANET routing protocol that can adapt to network topology changes to support QoS. In this paper, we propose a Topological change Adaptive Ad hoc On-demand Multipath Distance Vector (TA-AOMDV) routing protocol, which can adapt to high-speed node movement to support QoS. In this protocol, a stable path selection algorithm is designed, which not only takes node resources (residual energy, available bandwidth and queue length) as the path selection parameters, but also considers the link stability probability between nodes. Furthermore, in order to adapt to the rapid change of topology, link interrupt prediction mechanism is integrated into the protocol, which updates the routing strategy based on periodic probabilistic estimates of link stability. Different scenarios with node speed in the range of 10-50m/s, data rate in the range of 4-40kbps and number of nodes in the range of 10-100 are simulated on NS2 platform. Our results show that the QoS metrics (packet delivery rate, end-to-end delay, and throughput) of the proposed protocol are significantly improved when the node speed is higher than 30m/s although it is slightly better when the node speed is lower than 30m/s. Our on-demand multipath routing protocol demonstrates high potential to support QoS for high-speed MANET.

Mobile ad hoc networks (MANETs) are collection of distributed nodes which communicate using multi-hop wireless links. In order to manage the frequent topology change and ineffective communication, Distributed Spanning Tree (DST) interconnection technique can be used. DST technique guarantee network connectivity, efficient routing and maintain network performance in MANET. In MANET, nodes work for tasks of similar goal (common interest). So, most of the nodes try to access the similar data at different period. By using Data cache system (DCS), we can improve the efficiency of MANET to some extent [1]. In this paper, Ant Colony Optimization (ACO) technique is used to enhance the efficiency of data cache system in MANET at higher level. ACO technique improves the data transfer speed by finding optimal path between nodes of MANET in dynamic fashion. Analysis from simulation of our proposed work shows that data cache system efficiency can be improved using DST technique.

Now a day, Mobile Adhoc Networks (MANET) gained a lot of popularity in the research community. People realized that there is a commercial value in MANETs with the successful solutions of the most basic but important problems in network layer. Mostly all the applications that attracted interest in traditional wired networks (e.g. Audio/Video Transfer, Video Conferencing, Watching Online Movies/Sports, Camera-enabled Messenger, Online Gaming etc.) would attract interest for MANETs as well. Since real-time multimedia communications will be common in MANETs, there has been an increasing motivation on the introduction of QoS in such networks. But, many characteristics of MANETs make QoS provisioning a difficult problem. In MANETs, providing QoS guarantees is very difficult and challenging than in traditional wired networks, mainly due to multihop communications, contention for channel access, node mobility and a lack of central coordination. However, in the last few years, much research attention has focused on providing QoS guarantees in MANET routing protocols. QoS routing protocol/mechanism is key issue in provision of QoS in MANETs. There are number of QoS routing approaches have been proposed in literature, focusing on different QoS metrics but no particular protocol/mechanism provides overall solution. There are some major open research issues in this area such as QoS metric selection and cost function design, Multi-class traffic, Scheduling mechanism at source, Packet prioritization for control messages, QoS routing that allows preemption, and QoS in Heterogeneous networks. There are still many open questions that must be solved to improve the performance of QoS-aware routing protocols such as bandwidth/delay estimation, route discovery, resource reservation, route maintenance, cross-layer design, energy consumption, multicast QoS routing etc.

In Mobile Ad-hoc Networks (MANETs), each node is free to move and connect with one another over a wireless connection, without the requirement for a centralized controller or base station. These features make MANET useful and functional in a variety of areas, including tactical situations, sensor networks, rescue operations, and students on campus. However, this type of network also has a range of issues such as security, Quality of Service, dynamic topology, scalability, the absence of central management, and energy consumption. Since MANET nodes have little battery life, the power usage is among the most important design considerations in wireless ad-hoc networks. Each node is responsible for forwarding the packets to its neighboring nodes. Since the MANET does not contain a hierarchy, some nodes may not participate in forwarding the packets and prefer to keep their remaining energy for themselves; these nodes are called selfish nodes. The presence of selfish nodes in the MANET greatly affects the efficiency and activity of the network. The process of detecting and isolating the selfish node does not constitute an easy task. It still requires further investigation and study. Therefore, this survey is intended to determine, study and analyze some new detection mechanisms used in detecting selfish nodes in MANETs. It also classifies them into three categories which are credit-based, reputation-based, and acknowledgment-based techniques. In addition, it highlights some critical issues in MANET according to selfish behavior, and points out the necessary requirements for better improvement as well as fields for future research.

A Review on Cooperative Bait Based Intrusion Detection in MANET