Multicast In Mobile Ad Hoc Networks Research Articles

On delay performance study for cooperative multicast MANETs

Understanding the multicast delay performance of mobile ad hoc networks (MANETs) lays the foundation for multicast-intensive applications in future highly heterogeneous wireless network environments. This paper explores, for the first time, the multicast delay performance of MANETs under a general cooperative multicast scheme for routing protocol. The multicast scheme is based on two-hop relay multicast algorithm, where a packet can be sent to several relay nodes by source node, and destination nodes receive the packet from these relay nodes or their source node. The destination nodes may serve as relay nodes to forward packet to other ones with some probability. The multicast scheme is general in the sense that it can cover the available two-hop relay multicast algorithms with full cooperation and non-cooperation as special cases. Moreover, our multicast scheme can also cover two-hop relay unicast algorithm as special case when the number of destination nodes equals to one. To study the multicast delay performance, we first develop a Markov chain theoretical framework to fully characterize the packet delivery process under the general cooperative multicast scheme. With the help of this theoretical framework, we derive analytical expressions for the mean and variance of multicast delay. Finally, we present extensive simulation and theoretical results to validate our multicast delay analysis and to illustrate the impacts of network parameters on multicast delay performance.

Non-Asymptotic Capacity Study in Multicast Mobile Ad Hoc Networks

Extensive efforts on capacity studies for the mobile ad hoc networks (MANETs) mainly focus on either the unicast traffic or the asymptotic results under multicast traffic. However, the former ones cannot support future multicast-intensive applications, and the latter ones cannot reveal the real achievable non-asymptotic capacity, such that it still remains largely unknown in such networks. This paper, for the first time, investigates the non-asymptotic capacity in MANETs under a general packet routing scheme with multicast traffic, where each source has multiple destinations. Under the routing scheme, when the destinations move into the communication range of their source, a packet at source will be directly sent to destinations; otherwise, it can be replicated to multiple different relays, which help to forward it to destinations. To study the non-asymptotic capacity in the MANETs, we first develop the two Markov chain theoretical frameworks to characterize the fastest packet propagation process at source and the fastest packet reception process at destinations under the routing scheme. Based on these two theoretical frameworks, we then derive an analytical expression for the capacity. Finally, the simulation and numerical results are conducted to validate our theoretical capacity and also to explore the impact of system parameters on the capacity performance.

Generalized Cooperative Multicast in Mobile Ad Hoc Networks

Cooperative multicast serves as an efficient communication paradigm for supporting multicast-intensive applications in mobile ad hoc networks (MANETs). Available studies on cooperative multicast in MANETs mainly focus on either the full cooperation or the noncooperation, which fail to capture the more general cooperation behaviors among destination nodes. To address this issue, this paper proposes a general cooperative multicast scheme CM( $f,g, p,\tau$ ) with replication factor $f$ , multicast fanout $g$ , cooperative probability $p$ , and packet lifetime $\tau$ . With this scheme, a packet from source node will be replicated to at most $f$ distinct relay nodes, which forward the packet to its $g$ destination nodes, and with probability $p$ a destination node helps to forward the packet. Here, the packet has the lifetime of $\tau$ time slots. The scheme is flexible and general, and it covers the full cooperation ( $p = 1$ ) and the noncooperation ( $p = 0$ ) as special cases. A Markov chain theoretical model is further developed to depict the packet delivery process under the new scheme and help us to conduct analytical study on the corresponding expected packet delivery probability and packet delivery cost. Finally, extensive simulation and numerical results are provided for discussions.

An Energy Efficient Multicast Routing Protocol for MANET

An important and essential issue for multicast mobile ad-hoc networks (MANETs) is routing protocol design i.e. a major technical challenge due to the dynamism of the network. Mobile Ad-Hoc Network (MANET) is a dynamic, multi-hop and autonomous network composed of light wireless mobile nodes. A lot of control messages are required to build optimal multicast trees and maintaining group membership due to the dynamism of MANETs. Due to these overheads we consume greater energy resourses of mobile nodes and network resourses like wireless links bandwidth . This paper presents an effective multicast routing protocol for MANET with least control overhead. The protocol constructs shared multicast tree using the physical position of the nodes for the multicast sessions. To obtain the physical location of the nodes we use the concept of distributed location service , which effectively reduces the overheads for route searching and shared multicast tree maintenance.In this protocol we use the concept of small overlapped zones around each node for active topology maintenance with in the zone. To pursuit for an existing multicast tree outside the zone, constrained directional forwarding is used which ensure a good reduction in overhead in comparison to network wide flooding for search method.The protocol employs local connectivity technique and protective route reconfiguration on the basis of the current status of the nodes are being proposed which reduces the overhead, power and bandwidth requirement and try to increase the performance and reliability.

Moralism: mobility prediction with link stability based multicast routing protocol in MANETs

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.

The Role of Location Popularity in Multicast Mobile Ad Hoc Networks

In the asymptotic analysis of large scale mobile networks, most previous works assume that nodes move in all the cells identically. We put forward this line of research by considering location popularity, which is verified by recent experimental studies. Nodes tend to visit some popular locations and go to other locations less frequently. We first analyze its multicast capacity and delay under the traditional 2-hop store-carry and forward paradigm. With different location popularity distributions, network capacity and delay will vary according to the distribution exponent. As the popularity becomes more diverse, less concurrent transmissions are tolerated in the network, which brings down the performance. Observing that transmission opportunity is not fully utilized in popular cells for 2-hop paradigm, we put forward a 3-hop scheme, which is called store-carry-accelerate-forward scheme. In this 3-hop scheme, each packet is first sent to an initial relay, who carries the packets into the popular cells and then broadcasts to multiple nodes to accelerate the delivery. By so doing, we showed that the 3-hop scheme outperforms the 2-hop scheme for all popularity distributions. Furthermore, we study the delay-capacity tradeoffs for multicast under both schemes and the buffer needed for stability requirement. Our results reveals the joint impact of multicast and location heterogeneity on the design of transmission schemes, and may shed new insights for future studies.

Zone Based Secure Multicast Architecture for Intra-Cluster Communication in MANET

In mobile ad hoc networks (MANETs) in order to enhance efficiency, the multicast MANET is used for a sender node, which sends data packets to a number of nodes in the network through a multicast session. Due to the complicatedness in zone membership management and multicast packet forwarding over a dynamic topology, completion of efficient and scalable multicast with security in MANET becomes a challenge. In order to achieve a secure multicast architecture for MANETS, in this paper, we propose a Zone based Secure Multicast Architecture for Intra-cluster Communication in MANET. Initially, cluster creation is performed. Then, in a broad environment, a zone-based bidirectional tree is constructed and the zone leader is elected using trust value. Trust value is estimated from the Markov trust model. Finally, the secure voting process in the selected zone leader is made by using the elliptic curve discrete algorithm (ECDSA).

Supporting Efficient and Scalable Multicasting over Mobile Ad Hoc Networks

Group communications are important in Mobile Ad hoc Networks (MANETs). Multicast is an efficient method for implementing group communications. However, it is challenging to implement efficient and scalable multicast in MANET due to the difficulty in group membership management and multicast packet forwarding over a dynamic topology. We propose a novel Efficient Geographic Multicast Protocol (EGMP). EGMP uses a virtual-zone-based structure to implement scalable and efficient group membership management. A networkwide zone-based bidirectional tree is constructed to achieve more efficient membership management and multicast delivery. The position information is used to guide the zone structure building, multicast tree construction, and multicast packet forwarding, which efficiently reduces the overhead for route searching and tree structure maintenance. Several strategies have been proposed to further improve the efficiency of the protocol, for example, introducing the concept of zone depth for building an optimal tree structure and integrating the location search of group members with the hierarchical group membership management. Finally, we design a scheme to handle empty zone problem faced by most routing protocols using a zone structure. The scalability and the efficiency of EGMP are evaluated through simulations and quantitative analysis. Our simulation results demonstrate that EGMP has high packet delivery ratio, and low control overhead and multicast group joining delay under all test scenarios, and is scalable to both group size and network size. Compared to Scalable Position-Based Multicast (SPBM) [CHECK END OF SENTENCE], EGMP has significantly lower control overhead, data transmission overhead, and multicast group joining delay.

Design and simulation analysis of non-receiver aware and receiver aware multicast location prediction based routing protocols for mobile ad hoc networks

We present multicast extensions to our recently proposed Location Prediction Based Routing (LPBR) protocol, referred to as NR-MLPBR and R-MLPBR, to simultaneously reduce the number of multicast tree discoveries and number of links per tree and/or the hop count per source-receiver path in mobile ad hoc networks (MANETs). Nodes running NR-MLPBR are not aware of the receivers of the multicast group; R-MLPBR assumes each receiver node knows the identity of the other receivers of the group. Upon failure of a path to the source, a receiver attempts to locally construct a global topology using the location and mobility information collected during the latest broadcast tree discovery. NR-MLPBR predicts a path that has the minimum number of hops to the source and R-MLPBR predicts a path to the source that has the minimum number of non-receiver nodes. If the predicted path exists in the network at that time instant, the source accommodates the path as part of the multicast tree and continues to send multicast packets in the modified tree without attempting a broadcast discovery. Simulation results show that NR-MLPBR and R-MLPBR perform better than the minimum-hop based and minimum-link based on-demand multicast MANET routing protocols under different conditions of node mobility, density and group size. International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 1-21

Markov Chain Trust Model for Trust-Value Analysis and Key Management in Distributed Multicast MANETs

To increase efficiency in mobile ad hoc networks (MANETs), the multicast MANET is proposed for a sender that sends packets to several receivers through a multicast session. In MANETs, multicast group members frequently change due to node mobility; thus, supporting secure authentication and authorization in a multicast MANET is more critical than that in a wired network with a centralized certificate authentication (CA) server. This paper thus proposes a two-step secure authentication approach for multicast MANETs. First, a Markov chain trust model is proposed to determine the trust value (TV) for each one-hop neighbor. A node's TV is analyzed from its previous trust manner that was performed in this group. The proposed trust model is proven as an ergodic continuous-time Markov chain model. Second, the node with the highest TV in a group will be selected as the CA server. To increase reliability, the node with the second highest TV will be selected as the backup CA server that will take over CA when CA fails. The procedures of the secure authentication for group management are detailed. The security analysis of each procedure is analyzed to guarantee that the proposed approach achieves a secure reliable authentication in multicast MANETs. In addition, several famous attacks have been analyzed and discussed. Numerical results indicate that the analytical TV of each mobile node is very close to that of simulation under various situations. The speed of the convergence of the analytical TV shows that the analyzed result is independent of initial values and trust classes. This is a good feature of analytical models.

Mobile collaborative learning using multicast MANETs

Collaborative learning outside the classroom is vital for many educational disciplines. Three educational scenarios held outdoors are analysed. In the first scenario, students investigate the ancient architecture, archaeological artefacts and historical location at an archaeological site. In the second scenario, students investigate the environmental and natural resource management, endangered species and flora at a national forest. The third scenario describes collaborative game-based learning at outdoors. Multicast Mobile Ad Hoc Networks (MANETs) are employed to support students' communication and collaboration. Simulation results show the feasibility of multicast MANETs to support students' communication and collaboration during these three outdoor educational scenarios.

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

We present a simulation-based study of the impacts of different types of attacks on mesh-based multicast in mobile ad hoc networks (MANETs). We consider the most common types of attacks, namely rushing attack, blackhole attack, neighbor attack and jellyfish attack. Specifically, we study how 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. We also examine rushing attackers’ success rates of invading into the routing mesh when the number of attackers and their positions vary. The results enable us to suggest measures to minimize the impacts of the above types of attacks on multicast in MANETs.

Epidemic-based approaches for reliable multicast in mobile ad hoc networks

We present a classification of epidemic-based approaches utilized in the context of mobile ad hoc networks (MANET) with a focus on reliable multicast protocols. We provide a brief description of the other approaches to reliable multicasting in MANETs as well. Then, we describe our protocol, namely EraMobile, offering Epidemic-based Reliable and Adaptive Multicast for Mobile ad hoc networks. EraMobile's target is group applications requiring high-level of reliability and the protocol aims to provide fully reliable multicast data delivery with minimal network overhead even in the adverse network conditions. EraMobile utilizes an epidemic-based method in multicast operation to cope with dynamic and unpredictable topology changes arising from the mobility. Our epidemic mechanism does not require the maintenance of any tree- or mesh-like structure for multicasting. It also needs neither having global or partial view of the network nor having information of neighboring nodes and group members. Besides, it substantially minimizes the overhead incurred by eliminating redundant data transmissions. Another distinguishing feature of EraMobile is its capability of adapting to varying node densities in order to provide reliable data delivery in both sparse networks, where the network connectivity is prone to interruptions, and dense networks, where congestion is likely to occur. EraMobile is shown to achieve fully reliable multicast data delivery studied through extensive simulations by outperforming the other protocols compared, especially in terms of both packet delivery ratio and overhead efficiency.

A scalable explicit multicast protocol for MANETs

Group oriented multicast applications are becoming increasingly popular in mobile ad hoc networks (MANETs). Due to dynamic topology of MANETs, stateless multicast protocols are finding increased acceptance since they do not require maintenance of state information at intermediate nodes. Recently, several multicast schemes have been proposed which scale better with the number of multicast sessions than traditional multicast strategies. These schemes are also known as explicit multicast (Xcast; explicit list of destinations in the packet header) or small group multicast (SGM). In this paper, we propose a new scheme for small group multicast in MANETs named extended explicit multicast (E2M), which is implemented on top of Xcast and introduces mechanisms to make it scalable with number of group members for a given multicast session. Unlike other schemes, E2M does not make any assumptions related to network topology or node location. It is based on the novel concept of dynamic selection of Xcast forwarders (XFs) between a source and its potential destinations. The XF selection is based on group membership and the processing overhead involved in supporting the Xcast protocol at a given node. If the number of members in a given session is small, E2M behaves just like the basic Xcast scheme with no intermediate XFs. As group membership increases, nodes may dynamically decide to become an XF. This scheme, which can work with few E2M aware nodes in the network, provides transparency of stateless multicast, reduces header processing overhead, minimizes Xcast control traffic, and makes Xcast scalable with the number of group members.

DESIRE: Density Aware Heterogenous Overlay Multicast Forwarding Scheme in Mobile Ad Hoc Networks

Overlay multicast schemes for Mobile Ad hoc Networks (MANET) [1| have been proposed to remove non group members' dependency for multicast forwarding. However, since all packets are relayed from one group member to other group member in a form of unicast packet, they sometimes cause a lot of packets' collision and low resource utilization particularly where group members densely locate. In this paper, we propose a new forwarding scheme, DESIRE (Density awarE heterogeneous overlay multicast foRwarding schemE in MANET), for overlay multicast in MANET. DESIRE is significantly different from previous overlay multicast schemes in that it creates separate data forwarding path over overlay DDT (Data Delivery Tree) depending on density of group members. In dense environment, a zone is constructed and a scoped flooding is applied within it. On the other hand, in sparse environment, data dissemination is accomplished in a form of unicast packet similar to previous overlay multicast. By adapting scoped flooding in dense environment, it can reduce a lot of packets' collision and balance battery consumption by making use of mobile node's broadcast capability entirely. Also, in sparse environment, DESIRE can cope with network mobility very well since overlay DDT can remain static regardless of changes in physical topology. Such distinct advantages are evaluated by simulation. Generally, better performance is shown with large group members than small group members.