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Multicast communication plays a pivotal role in Edge based Mobile Ad hoc Networks (MANETs). MANETs can provide low-cost self-configuring devices for multimedia data communication that can be used in military battlefield, disaster management, connected living, and public safety networks. A Multicast communication should increase the network performance by decreasing the bandwidth consumption, battery power, and routing overhead. In recent years, a number of multicast routing protocols (MRPs) have been proposed to resolve above listed challenges. Some of them are used for dynamic establishment of reliable route for multimedia data communication. This article provides a detailed survey of the merits and demerits of the recently developed techniques. An ample study of various Quality of Service (QoS) techniques and enhancement is also presented. Later, mesh topology-based MRPs are classified according to enhancement in routing mechanism and QoS modification. This article covers the most recent, robust, and reliable QoS-aware mesh based MRPs, classified on the basis of their operational features, and pros and cons. Finally, a comparative study has been presented on the basis of their performance parameters on the proposed protocols. [ABSTRACT FROM AUTHOR]

In this paper, we propose a Multi-Constraint Quality-of-Experience (QoE) centric Routing (MCQR) technique for efficient real-time video streaming over Mobile Ad-hoc Networks (MANETs). The dynamic estimation of link quality metric during MCQR route discovery process is the key of enhancing QoE at end user. MCQR limits end-to-end delay and jitter of received data packets by selecting long lifetime routes with maximum permissible delay. This minimizes the distortion caused fluctuations in perceived video. To prove the effectiveness of MCQR for real-time video streaming, we have designed a hybrid MANET consisting of simulated nodes and physical machines. In our hybrid network, the source and destination nodes are video traffic generators and receivers running on physical devices. Emulation results are obtained using real-time video streaming over high fidelity virtual wireless network, and conforming that the MCQR protocol provides satisfactory QoE to end users as compared to existing similar techniques. The packet delivery ratio of MCQR is higher than 90 % and its mean opinion score is higher than three (i.e., satisfactory) even when mobility and shadowing effects are kept high in target network scenarios. These improvements are achieved along with still maintaining similar or better routing overhead and processing delays. [ABSTRACT FROM AUTHOR]

In MANETs, real-time multimedia applications make Quality of Service ( QoS ) support, a crucial issue regarding terms of increased throughput, reduced jitter, and available bandwidth. Most of the existing routing protocols focus on straight forward hop-count metric and are less adaptable to densely distributed and highly mobile networks. Therefore, Multicast communication with QoS in densely populated highly dynamic network an exciting research challenges. The objective of the present paper is to introduce a QoS aware routing metric that determines a reliable forwarding node based on Link Stability cost Function ( LSF ). A mesh of Multicast routes between Multicast source and destinations has been established using nodes with a maximum LSF . The principle theme underlying our protocol is optimum contention count that can be estimated with the help of received signal strength. The proposed protocol comprises the following stages:(1) Calculation of Link Stability Factor (2) Determination of maximum LSF value (3) Pruning adjacent nodes (4) Creation of a mesh consisting of more stable forwarding nodes (5) Creation of a mobile network in which no node remains isolated, as well as nodes, face lesser contention. Our proposed protocol has been demonstrated on an existing mesh-based Multicast routing protocols, ODMRP. Simulations are carried out on Exata/Cyber simulator, and obtained results are compared with that of ODMRP. The comparative analysis reveals that our protocol is more efficient in contrast to ODMRP, LSMRP, and MMRNS, regarding performance parameters like Packet Delivery Ratio ( PDR ), Average End-to-End Latency and Average Route Lifetime. Also, we have analyzed the impact of minimum and maximum contention count on PDR and delay. [ABSTRACT FROM AUTHOR]

The growing popularity of multimedia applications and services needs to support several quality of service metrics such as high throughput, low energy, and jitter, which is a challenging task in mobile ad hoc networks. Because of limited bandwidth, energy constraints, dynamic topology, transmission errors, and fluctuating link stability, the links between adjacent nodes are often not reliable and may break because of node mobility. Link breakage initiates the process of rerouting either at the sender node (the node at which the link breaks) or at the source node. In either case, it leads to packet loss, delivery delays, and increased control overheads. Hence, to attain a minimum quality of service, routing protocols must address the dynamic network topology. Uncertain and varying movement of nodes necessitates stability of the links between such nodes. The objective of this paper is to propose 2 protocols, the first based on link stability and the other based on route stability. Link stability identifies a stable link from the available links to the next hop and determines a stable end-to-end route. The probability of successful transmission of periodic packets is used as a link stability metric to assess the stable path. Acknowledgment -free packets are used to check connectivity in the network. Increased probability of successful transmission implies that the selected link is sustained for longer duration and can deliver packets more reliably or, as a consequence, results in a stable link to deliver a better data rate. With a stable link, there is a reduced possibility of retransmissions, reduced end-to-end delay, reduced control overheads, and enhanced data delivery ratio. Selection of the most stable route for data transmission improves the performance. Experimental results from simulations performed on EXata/Cyber v2.0 simulator reveal that our proposed protocols are an improvement over the existing protocols in terms of packet delivery ratio, average end-to-end delay, and average route lifetime, even without route optimization with the minor increase in control packets. A case study of the application of proposed protocols is also presented. [ABSTRACT FROM AUTHOR]

In recent research, link stability is getting tremendous attention in mobile adhoc networks (MANETs), because of several impediments that occur in a reliable and robust network. Link stability metric is used to improve network performance in terms of end-to-end delay, data success delivery ratio (DSDR) and available route time (ART). Energy consumption, bandwidth and communication delay of major concern in ad hoc networks. A high mobility of MANET nodes reduces the reliability of network communication. In a dynamic networks, high mobility of the nodes makes it very difficult to predict the dynamic routing topology and hence cause route/link failures. Multicast in MANETs is an emerging trend that effectively improves the performance while lowering the energy consumption and bandwidth usage. Multicast routing protocol transmits a packet to multicast a group at a given time instant to achieve a better utilization of resources. In this paper, node mobility is considered to map better their movement in the network. So, the links with long active duration time can be identified as a stable link for route construction. Variation in signal strength is used to identify whether the direction of the node is towards or away from estimating node. We consider signal strength as QoS metric to calculate link stability for route construction. Efforts are made to identify the link with highly probable longer lifetime as the best suitable link between two consecutive nodes. We predict the movement time of nodes that define the route path to the node destination. Exata/cyber simulator is used for network simulation. The simulation results of the proposed routing protocol are compared with on-demand multicast routing protocol and E-ODMRP, which works on minimum hop count path. Analysis of our simulation results has shown improvement of various routing performance metrics such as DSDR, ART, routing overhead and packet drop ratio. [ABSTRACT FROM AUTHOR]

Mobile ad hoc networks (MANETs) are vulnerable to various types of attacks due to inherently in-secure wireless communication medium and multihop routing communication process. In this paper, we analyze the behavior and impact of JellyFish attack over TCP-based MANETs. We have implemented and evaluated all three variants of JellyFish attack namely JF-reorder, JF-delay and JF-drop through simulation processes. These attacks exploit the behavior of closed loop protocols such as TCP and disturb the communication process without disobeying any protocol rules, thus the detection process becomes difficult. Consequently, traffic is disrupted leading to degradation in network throughput. Through extensive simulation results that are obtained using an industry standard scalable network simulator called EXata-Cyber, impact of these attacks in terms of network throughput, overhead incurred and end-to-end delay is analyzed and used for devising detection and countermeasure. We have proposed a light-weight direct trust-based detection (DTD) algorithm which detect and remove a JellyFish node from an active communication route. In our proposed DTD algorithm, each node uses locally calculated trust values which are collected over a time period to identify whether its neighbor node is a JF-attacker or not. [ABSTRACT FROM AUTHOR]

In this paper, we develop and evaluate an adaptive self-configurable routing framework that can deal with dynamic nature of mobile ad hoc networks and provides quality-of-service (QoS) guarantees for efficient video streaming. Proposed framework mainly consists of two major components. Firstly, it is a reactive bandwidth-aware node-disjoint multipath routing protocol which determines routes based on the specified bandwidth requirements of the requesting application. The second component of the framework is a session admission control (SAC) process that permits or denies a session to enter into the network based on the current availability of network bandwidth. We also propose methods to handle QoS violations caused by network mobility and congestion by keeping backup routes, performing local route recovery, avoiding routing through short-lived low quality links and periodic monitoring of the active transmission routes. To verify our proposed algorithms, the network with H.264/SVC encoded video traces which are generated from real-time video traffic is used for modeling the behaviour of the source nodes. It has been observed that reactively discovered and maintained routes on the basis of the most recent information about network topology and available resources can significantly improve the admission decision accuracy of SAC process, in turn improving the quality of received video traffic significantly. [ABSTRACT FROM AUTHOR]

ABSTRACT Collusion attack is an attack against Optimised Link State Routing (OLSR) protocol in mobile ad hoc network. Two malicious nodes work together so that routes to the target (victim) node(s) are not established in the network. Multipoint relay (MPR) selection process in OLSR is exploited to achieve this route denial. Packet delivery ratio for the target drops to 0% for nodes at distance of 3 hops or more. In this paper, we propose use of convergence characteristics of OLSR in designing effective, resource efficient countermeasures for packet dropping attacks such as collusion attack. We propose a detection method and countermeasure Scruple where discovery packets called ScruplePackets are injected to probe routes from target node to its three-hop neighbours. Acquired information is analysed to conclude if the node is a target of collusion attack. We also propose a novel attack-resistant method named Forced MPR Switching OLSR in which a node temporarily blacklists potential attackers on observing symptoms of the attack, thereby, forcing recomputation of its MPR set. Proposed approaches incur minimal penalty on network performance. Simulations conducted on Network Simulator 3 confirm effectiveness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]