Multicast routing in mobile ad hoc networks by using a multiagent system

Multicast routing protocols proposed for mobile ad hoc networks have certain limitations. Most of these protocols try to discover the route on-demand by flooding route request messages, which results in increased end-to-end latency and also consumes considerable amount of network bandwidth. These limitations make protocols not suitable for real-time multimedia communication. In this paper, we have presented an efficient mobile agents aided multicast routing (MAMR) protocol which overcomes these limitations. The protocol is a hybrid protocol where intelligent mobile agents can been integrated with existing on-demand multicast routing protocols such as multicast ad hoc on-demand distance vector (MAODV) routing protocol, on-demand multicast routing protocol (ODMRP) routing protocol and others. Here, the mobile agents move around the network and collect the routing information. This routing information assists on-demand multicast routing protocols in discovering the route in a definite path instead of flooding the route request messages, thereby achieving better end-to-end latency and reduced control traffic in the network. We have used MAODV protocol as an underlying protocol with mobile agents. The proposed MAMR protocol and MAODV have been compared through extensive simulations with end-to-end latency, packet delivery ratio and control overhead as performance parameters

The Multicast Ad hoc On-Demand Distance Vector (MAODV) protocol achieves multicast routing in self-organizing wireless mobile on-demand networks, e.g., Mobile Ad-hoc Networks (MANETs). However, unreliable wireless links degrade network reliability and network goodput, and the unreliable link problem becomes worse in multicasting because a multicast tree consists of more number of wireless links. MAODV adopts a broadcast-type local repair, and thus yields a large number of broadcast-type repair messages, increases extensive control overhead, and involves largely power consumption. Thus, a cross-layer unicast-type multihop local repair approach is proposed to recover broken links in multicasting MANETs. Additionally, the cross-layer mechanism provides mobile nodes to send a cross-layer message to the TCP sender to keep current congestion window (cwnd) and slow start threshold (ssthresh) when downstream links are temporarily broken, and then increases network goodput. Finally, the optimal number of neighbor-tiers is analyzed and the optimal substitute node is identified. Numerical results demonstrate that the proposed approach outperforms other approaches in successful repair rate, control message overhead, packet delivery ratio, and network goodput.

Emergent Intelligence Based QoS Routing in MANET

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.

Recently, the study of multicast routing attracts more attentions in MANET. Multicast Ad Hoc On-Demand Distance Vector (MAODV) protocol, which is multicast operation of the Ad hoc On-Demand Distance Vector (AODV) routing protocol, enables dynamic, self-starting, multihop routing between participating mobile nodes wishing to join or participate in a multicast group within an Ad Hoc network. Through analyzing its operation mechanism, we present a probability based multicast routing protocol with energy constrained (PBMR),in which a hybrid probability forwarding strategy is adopted. When a node wants to join a multicast tree, it floods a RREQ-Join message to its neighbors, when the neighbors receive this message, the neighbor with much energy left has a high probability to forward the message, and so on. By making correctness proof and complexity analysis of PBMR, this paper evaluates MAODV and PBMR with extensive simulations, the results show that PBMR has a better jitter than MAODV and a more balance in energy consumption. On the one hand, it saves the energy of the network system; on the other hand, it has a longer network lifetime and a more stable routing than MAODV and successfully solves the inconsistent problem of energy and scalability.

Mobile Ad-hoc Network (MANET) comprise of independent ambulant nodes with no any stable infrastructure. All mobile nodes are co-operatively transfer their data packets to different mobile nodes in the network. Mobile nodes are depends on intermediate nodes when transmission range beyond limit i.e. multi hop network. As MANET is a highly dynamic network, mobile nodes can leave and join a network at anytime. Security is the biggest issue in MANET as MANET is infrastructure-less and autonomous. In MANET, correspondence between two mobile nodes is performed by routing protocols wherein every versatile node can make directly communication with other versatile node. In the event that both portable nodes are inside a transmission range of each other, then they can straightforwardly make communication with each other. Otherwise, transmission is done through the intermediate node. The nature of its wireless nature is also additionally turns into the purpose of its greatest vulnerability. In this manner, diminishing the confidence level of the system as it appropriate to availability, integrity, reliability and privacy concerns. There are different routing protocols for providing security that are designed based on various cryptographic techniques. To obtain a rapid knowledge of security design, we are giving a review on different cryptographic techniques to secure MANET. In this review, we presents security techniques and protocols related to cryptographic techniques.

Multi-constrained Quality of Service (QoS) routing is to find a feasible path that satisfies multiple constraints simultaneously, which is a big challenge for Mobile Ad hoc Networks (MANETs) where the topology may change constantly. Most of the conventional protocols are designed to concentrate on either maximizing the throughput or decreasing the end-to-end delay. These single constrained QoS routing protocols have inherent shortcomings in real time applications where the communication requires meeting stringent requirements on delay, delay-jitter, cost and other QoS metrics. In this paper we propose an agent based Multi-Constrained QoS aware multicast routing scheme based on MAODV (MC_MAODV) which uses a set of static and mobile agent. It depicts QoS multicast model with multiple constraints which may deal with bandwidth reservation, delay constraint and packet loss to multicast session. Here the mobile agents are used to find multicast routes, create the backbone for a reliable multicasting and to adapt to dynamic topology. Multi-path strategy is introduced to reduce the time consumption of rerouting when the link fails due to node mobility. Also, the source node can utilize the best path for the data transmission to meet multiple QoS requirements. Extensive simulations have been conducted to evaluate the performance of MC_MAODV using Network Simulator (NS-2). The simulation results show that the proposed scheme performs better than traditional MAODV in terms of improving packet delivery ratio and minimizing end-to-end delay.KeywordsMANETsmulti-constrained routing multicastingclustersend-to-end delaypacket loss ratio

Networks are being used in various areas and the demand of users nowadays has motivated the emergence of the Mobile Ad Hoc Network (MANET). MANET is a dynamic network without fixed infrastructure due to their wireless nature and can be deployed as multi-hop packet networks. It is a wireless network and has dynamic topology due to its node mobility. There are two types of MANET, homogeneous and heterogeneous MANET. An architecture has been designed in previous work to model these two types of MANET. Three scenarios have been defined from this architecture: scenario I (communication entirely within MANET, homogeneous MANET), scenario II (communication between MANET and wireless LAN, heterogeneous MANET) and scenario III (communication between MANET with wireless LAN and wired LAN, heterogeneous MANET). MANET has its own routing protocols which can compromised with frequent route exchange, dynamic topology, bandwidth constraint and multi-hop routing. Ad hoc On Demand Distance Vector (AODV) is one of the routing protocols in MANET. The aim of this research is to assess the effects of different packet size with the implementation of AODV routing protocols in homogeneous and heterogeneous MANET through the simulation method. The three scenarios above have been developed in the OMNeT++ network simulator. The results achieved from the test have been evaluated using the metrics assigned, throughput and packet delivery ratio (PDR). The tests show that the increase of throughput and PDR performance was parallel with the increase of packet size. From the test also, we can conclude that the performance due to the packet size effect in homogeneous MANET is better than in heterogeneous MANET.

Mobile Ad Hoc Network (MANET) is a dynamic network without fixed infrastructure due to their wireless nature and can be deployed as multi-hop packet networks. It is a wireless network and has dynamic topology due to its node mobility. Networks are being used in various areas and the demand of users nowadays has motivated the emergence of the heterogeneous MANET. Compared to homogeneous MANET, heterogeneous MANET is more open to other types of network for example wireless LAN, cellular network and fixed network. In MANET, the concern is more to configuration and one of the important elements in configuration is routing. Ad hoc On Demand Distance Vector (AODV) is one of the routing protocols in MANET which can compromise with MANET characteristics. The aim of this research is to assess the performance of AODV in different mobility speed for homogeneous MANET and heterogeneous MANET through the simulation method. The simulation scenarios derived from the HetMAN architecture (as been discussed in previous work) have been developed in the OMNeT++ network simulator. The results achieved from the test have been evaluated using the metrics assigned; throughput and packet delivery ratio (PDR). The tests show that, as the speed increase, the throughput and PDR decrease for both homogeneous and heterogeneous MANET. From the test also, we can conclude that the performance in homogeneous MANET is better than in heterogeneous MANET.

PUMA (Protocol for Unified Multicasting through Announcements) is a mesh-based multicast routing protocol for mobile ad hoc networks distinguishing from others in its class by the use of only multicast control packets for mesh establishment and maintenance, allowing it to achieve impressive performances in terms of packet delivery ratios and control overhead. However, one of the main drawbacks of the PUMA protocol is that the core of the mesh remains fixed during the whole execution process. In this paper, we present an improvement of PUMA by introducing to it an adaptive core selection mechanism. The improved protocol produces higher packet delivery ratios and lower delivery time while incurring only little additional control overhead.

Mobile Ad Hoc Networks (MANETs) consist of several nodes that are mobile in nature. The random and unpredictable node mobility in MANETs has negative impact on the network performance as it makes the network prone to frequent link breakages which increase packet loss and control overhead. Reliable MANET can be achieved through fast link failures detection that enables fast notification to be delivered to sources in order to make proper reaction. Therefore, the research work in this paper presents an effective topology-aware method, called Route Failure Prediction (RFP), which predicts the link breakage before it actually occurs in source routing networks. A node that utilizes RFP divides the area within transmission range into regions based on the signal strength received from neighbors. It calculates the changing rate of its location and update the upstream node if it is about to move out of the transmission range to avoid communication disruption. The performance of RFP was evaluated using ns-2 and compared to that of DSR. The experimental results gained from simulations were analyzed in terms of Packet Delivery Ratio (PDR), Control Overhead (COH), and the End-to-End Delay with respect to the number of events of link breakage happened during the experiments. The numerical results showed that RFP outperforms DSR significantly and offers reliable data transfer between sources and destinations.

Due to its simplicity, efficiency, and robustness to mobility, the On-Demand Multicast Routing Protocol (ODMRP) becomes a standout amongst the most broadly utilized multicast routing protocols in mobile ad hoc networks (MANETs). However, the robustness of ODMRP comes at the expense of incurring a high control overhead to the network. The Enhanced ODMRP (EODMRP) proposed a dynamic refresh interval for the multicast mesh based on the network feedback on real disconnections experienced by the multicast network members. Veritably, EODMRP decreased the network control overhead at the cost of obtaining a low packet delivery ratio especially in high mobility conditions of the network. In this paper, two protocols, as improvements to both ODMRP and EODMRP, are proposed where the refresh interval is basically adapted based on the source moving speed and the number of disconnections reported by multicast members. Furthermore, we proposed an impressive local recovery to be employed in both protocols, which includes new setup and failure mechanisms that contribute effectively to boosting the performance of our proposed protocols. Since the majority of nodes in MANET rely on batteries, the main contribution of this research is to limit the amount of control information that is passed between nodes (i.e., reducing the control overhead over that in ODMRP) while maintaining a better packet delivery ratio than EODMRP.

Mobile Ad hoc Networks (MANET) are structure less, autonomous wireless networks with mobile nodes that dynamically establish data transmission connections. Due to dynamic topological change, MANET routes are unbalanced and break repeatedly. Hence, providing efficient and reliable data delivery with effective utilization of network resources is a challenging issue to be considered in MANET. This paper proposes an instant-runoff Ranked Decision Forests Probit Regression-based Connectionist Multilayer Deep Neural Network (IRDFPR-CMDNN) for efficient data transmission and higher data delivery with a minimum end-to-end delay. This IRDFPR-CMDNN method performs route identification, data delivery, and route maintenance with more than three layers. Then the mobile nodes are sent to the input layer of the Connectionist Multilayer Deep Neural Network. In hidden layer 1, the Instant-runoff Ranked Decision Forests algorithm is applied for classifying the mobile nodes depending on the residual energy and load capacity. With selected mobile nodes, the Probit Regression is applied for finding the nearest neighboring nodes in the second hidden layer based on the link quality and received signal strength for route path establishment. Then multiple paths for routing are established from source to destination node and start to perform the data transmission. If link failure occurs during the data transmission, another alternative route with better link quality is selected for routing. In this way, energy-efficient data transmission is performed from source to destination with a higher data delivery rate and minimal time consumption. Experimental evaluation is carried out on energy consumption, packet delivery ratio, packet drop rate, throughput, and end-to-end delay with varying numbers of mobile nodes and data packets. Simulation results show that the IRDFPR-CMDNN technique effectively enhances data delivery, throughput and minimizes energy consumption, packet loss rate, delay with respect to conventional methods.

Security has become important to mobile ad hoc networks (MANETs) due mainly to their use for many mission and life-critical applications. However, the broadcast nature of inter-node communications and node mobility in MANETs make it very challenging to secure MANETs. Moreover, their constantly changing topology causes network node density and neighbor relationships to change dynamically. This paper presents an intrusion detection system (IDS) for MANETs at the application layer. The IDS utilizes (1) both anomaly and misuse detection schemes to identify attacks in MANETs and (2) mobile agents (MAs) to augment each node's intrusion-detection capability. In particular, each node is equipped with a local IDS, and MAs will be dispatched periodically or on-demand to augment each node's IDS. We present the design of this IDS and the overall network structure, as well as the methods for authenticating and dispatching MAs. We also evaluate the trade-offs between different design parameters of MAs.

This dissertation presents novel approaches to modeling and analyzing security and resource allocation in mobile ad hoc networks (MANETs). The research involves the design, implementation and simulation of different models resulting in resource sharing and security’s strengthening of the network among mobile devices. Because of the mobility, the network topology may change quickly and unpredictably over time. Moreover, data-information sent from a source to a designated destination node, which is not nearby, has to route its information with the need of intermediary mobile nodes. However, not all intermediary nodes in the network are willing to participate in data-packet transfer of other nodes. The unwillingness to participate in data forwarding is because a node is built on limited resources such as energy-power and data. Due to their limited resource, nodes may not want to participate in the overall network objectives by forwarding data-packets of others in fear of depleting their energy power. To enforce cooperation among autonomous nodes, we design, implement and simulate new incentive mechanisms that used game theoretic concepts to analyze and model the strategic interactions among rationale nodes with conflicting interests. Since there is no central authority and the network is decentralized, to address the concerns of mobility of selfish nodes in MANETs, a model of security and trust relationship was designed and implemented to improve the impact of investment into trust mechanisms. A series of simulations was carried out that showed the strengthening of security in a network with selfish and malicious nodes. Our research involves bargaining for resources in a highly dynamic ad-hoc network. The design of a new arbitration mechanism for MANETs utilizes the Dirichlet distribution for fairness in allocating resources. Then, we investigated the problem of collusion nodes in mobile ad-hoc networks with an arbitrator. We model the collusion by having a group of nodes disrupting the bargaining process by not cooperating with the arbitrator. Finally, we investigated the resource allocation for a system between agility and recovery using the concept of Markov decision process. Simulation results showed that the proposed solutions may be helpful to decision-makers when allocating resources between separated teams.