Efficient Route Selection Scheme in MANET Using Enhanced AODV Protocol

Mobile Ad Hoc network comprises of mobile nodes communicating over wireless medium. Due to ease of communication and flexibility, MANET has become an active area of research in wireless communication. However, issues such as limited battery capacity, dynamic topology and node mobility cause frequent link breakage due to which reroute discovery process is required to be initiated resulting in increase in latency and routing overheads. Many research works have been carried out for improvement of an existing routing scheme, however they do not scale-up well to provide stable and energy efficient route. This paper introduces a novel routing algorithm ENH-AODV (Enhanced AODV) that focuses on selection of an efficient route on the basis of quality of both links and nodes impending during route discovery process. In addition, each node maintains a list, consisting of details of nearby nodes with good energy level through hello mechanism. Simulation is carried out over network simulator and results prove that the proposed scheme is more effective and advantageous than AODV in terms of normalized routing load, end to end delay, packet delivery ratio and throughput.

     

A fully distributed replica allocation scheme for an opportunistic network

An opportunistic network (OPPNET) consists of diverse mobile nodes with various mobility patterns. Numerous mobility patterns and the resource constraints of mobile nodes lead to network partitioning that result in system performance degradation including low data accessibility. In a traditional mobile ad hoc network (MANET) which is similar to an OPPNET, replica allocation schemes have been proposed to increase data accessibility. Although the schemes are efficient in a MANET, they may not be directly applicable to an OPPNET because the schemes are based on a grouping of mobile nodes. It is very difficult to build groups based on network topology in an OPPNET because a node in an OPPNET does not keep its network topology information. In this paper, we propose a novel replica allocation scheme for an opportunistic network called the Snooping-based Fully Distributed replica allocation scheme. The proposed scheme allocates replicas in a fully distributed manner without grouping to reduce the communication cost, and fetches allocated replicas utilizing a novel candidate list concept to achieve high data accessibility. In the proposed scheme, a node can fetch replicas opportunistically based on the candidate list. Consequently, the proposed replica allocation scheme achieves high data accessibility while reducing the communication cost significantly. Extensive simulation results demonstrate that the proposed scheme reduces the communication cost and improves data accessibility over traditional schemes.     

An EDRI-based approach for detecting and eliminating cooperative black hole nodes in MANET

Mobile Ad hoc Network (MANET) is a self-configurable, self-maintenance network with wireless, mobile nodes. Special features of MANET like dynamic topology, hop-by-hop communications and open network boundary, made security highly challengeable in this network. From security aspect, routing protocols are highly vulnerable against a wide range of attacks like black hole. In black hole attack malicious node injects fault routing information to the network and leads all data packets toward it-self. In this paper, we proposed an approach to detect and eliminate cooperative malicious nodes in MANET with AODV routing protocol. A data control packet is used in order to check the nodes in selected path; also, by using an Extended Data Routing Information table, all malicious nodes in selected path are detected, then, eliminated from network. For evaluation, our approach and a previous work have been implemented using Opnet 14 in different scenarios. Referring to simulation results, the proposed approach decreases packet overhead and delay of security mechanism with no false positive detection. In addition, network throughput is improved by using the proposed approach.     

Distributed Topology Construction in ZigBee Wireless Networks

Topology control is one of the important techniques in wireless multi-hop networks to preserve connectivity and extend the network lifetime. This is more significant in ZigBee, since the address assignment scheme is tightly coupled with topology construction. For example, there can be orphan nodes that cannot receive the network address and isolated from the network due to predefined network configurations. In this paper, we propose a distributed topology construction algorithm that controls the association time of each node in order to solve the orphan node problem in ZigBee as well as construct an efficient routing tree topology. The main idea of the distributed topology construction algorithm is to construct primary backbone nodes by propagating the invitation packets and controlling the association time based on the link quality. Since the dynamically selected primary nodes are spread throughout the network, they can provide backbone to accept the association requests from the remaining secondary nodes which are majority in a network. In the performance evaluation, we show that the proposed topology construction algorithm effectively solves the orphan node problem regardless of network density as well as provides efficient tree routing cost comparable to the approximation algorithm for degree constrained minimum routing cost tree (DC-MRCT) problem.     

Friend-assisted intrusion detection and response mechanisms for mobile ad hoc networks

Nowadays, a commonly used wireless network (i.e., Wi-Fi) operates with the aid of a fixed infrastructure (i.e., an access point) to facilitate communication between nodes. The need for such a fixed supporting infrastructure limits the adaptability and usability of the wireless network, especially in situations where the deployment of such an infrastructure is impractical. Recent advancements in computer network introduced a new wireless network, known as a mobile ad hoc network (MANET), to overcome the limitations. Often referred as a peer to peer network, the network does not have any fixed topology, and through its multi hop routing facility, each node can function as a router, thus communication between nodes becomes available without the need of a supporting fixed router or an access point. However, these useful facilities come with big challenges, particularly with respect to providing security. A comprehensive analysis of attacks and existing security measures suggested that MANET are not immune to a colluding blackmail because such a network comprises autonomous and anonymous nodes. This paper addresses MANET security issues by proposing a novel intrusion detection system based upon a friendship concept, which could be used to complement existing prevention mechanisms that have been proposed to secure MANETs. Results obtained from the experiments proved that the proposed concepts are capable of minimising the problem currently faced in MANET intrusion detection system (IDS). Through a friendship mechanism, the problems of false accusations and false alarms caused by blackmail attackers in intrusion detection and response mechanisms can be eliminated.     

基于UCDS的战术网络拓扑构建研究

在战术MANET中,底层通信的拓扑结构是不断变化的。寻找最小连通子图(作为一个网络拓扑结构的主干)是在MANET的MAC层设计中网络拓扑构建的有效方法。在战术网络环境下研究用于广播的连通支配集构建算法,阐述了一种分布式的连通支配集算法(UCDS),该算法采用启发式规则选取支配节点及其连接节点。通过与其他相关研究对比分析,表明UCDS具有实施简单、执行速度快、消息复杂度低的特点,同时具备一定的灵活和抗毁能力,并能够实际应用于路由优化和低速率下节点的移动自适应。     

DEBH: detecting and eliminating black holes in mobile ad hoc network

Security in mobile ad hoc network (MANET) is one of the key challenges due to its special features e.g. hop-by-hop communications, dynamic topology, and open network boundary that received tremendous attention by scholars. Traditional security methods are not applicable in MANET due to its special properties. In this paper, a novel approach called detecting and eliminating black holes (DEBH) is proposed that uses a data control packet and an additional black hole check table for detecting and eliminating malicious nodes. Benefiting from trustable nodes, the processing overhead of the security method decreases by passing time. Ad hoc on-demand distance vector (AODV) routing protocol is used as the routing protocol in our design. After finding the freshest path using AODV, our design checks the safety of selected path. In case of detecting any malicious node, it is isolated from the entire network by broadcasting a packet that contains the ID of malicious nodes. Simulation results show that DEBH increases network throughput and decreases packet overhead and delay in comparison with other studied approaches. Moreover, DEBH is able to detect all active malicious nodes which generates fault routing information.     

LSCR:一种Mobile Ad hoc网络链路状态分组路由算法

本文提出了一种Mobile Ad hoc网络(Manet)链路状态分组路由算法(Link State-hased Cluster Routing Algo-rithm-LSCR)，该算法对Manet节点进行动态分组，每一组选举出一个具有最大度数的头结点(CH-Cluster Header)，该cH负责本组信息的管理、组内结点与组外结点之间的通信以及与其他组的CH之间交换链路状态信息等工作．本算法将改进的链路状态协议与分组路由协议有机结合，有效提高了Manet网络的路由效率．分析和实验结果表明，这种算法具有路由收敛速度快、维护成本相对较低，数据包发送成功率高，发送等待时间短等特点。     

Constructing a MANET Based on Clusters

This paper proposes a scheme for constructing a mobile ad hoc network (MANET) based on clusters. The proposed MANET architecture is made up of two hierarchies. One hierarchy is the backbone network which is made up of cluster heads and associate nodes, and the other hierarchy is the cluster which is made up of one cluster head and multiple cluster members. In the proposed cluster generation algorithm, the number of potential cluster members is used as a metric, and it is always the new node with the maximum number of potential cluster members that is elected as a cluster head. In this way, the number of cluster heads is minimized. In this scheme, only one associate node is used to achieve the communication between two cluster heads, so the number of nodes included in the backbone network is minimized. This scheme also proposes the cluster merging algorithm in order to maintain the minimum number of cluster heads. In the proposed cluster repair algorithm, if a cluster head fails/moves out of the cluster, then a new cluster head is elected to maintain the cluster stability. From the perspective of the cluster stability, this paper analyzes the performance parameters of the proposed scheme, and the data results show that the proposed scheme improves the MANET stability.     

Location aided probabilistic broadcast algorithm for mobile Ad-hoc network routing

On-demand routing protocols are widely used in mobile Ad-hoc network (MANET). Flooding is an important dissemination scheme in routing discovering of on-demand routing protocol. However, in high-density MANET redundancy flooding packets lead to dramatic deterioration of the performance which calls broadcast storm problem (BSP). A location-aided probabilistic broadcast (LAPB) algorithm for routing in MANET is proposed to reduce the number of routing packets produced by flooding in this paper. In order to reduce the redundancy packets, only nodes in a specific area have the probability, computed by location information and neighbor knowledge, to propagate the routing packets. Simulation results demonstrate that the LAPB algorithm can reduce the packets and discovery delay (DD) in the routing discovery phase.     

Trust Based Detection and Elimination of Packet Drop Attack in the Mobile Ad-Hoc Networks

The mobile ad hoc network (MANET) is communication network of a mobile node without any prior infrastructure of communication. The network does not have any static support; it dynamically creates the network as per requirement by using available mobile nodes. This network has a challenging security problem. The security issue mainly contains a denial of service attacks like packet drop attack, black-hole attack, gray-hole attack, etc. The mobile ad-hoc network is an open environment so the working is based on mutual trust between mobile nodes. The MANETs are vulnerable to packet drop attack in which packets travel through the different node. The network while communicating, the node drops the packet, but it is not attracting the neighboring nodes to drop the packets. This proposed algorithm works with existing routing protocol. The concept of trusted list is used for secure communication path. The trusted list along with trust values show how many times node was participated in the communication. It differentiates between altruism and selfishness in MANET with the help of energy level of mobile components. The trust and energy models are used for security and for the differentiation between altruism and selfishness respectively.     

Proficient link state routing in mobile ad hoc network-based deep Q-learning network optimized with chaotic bat swarm optimization algorithm

Mobile ad-hoc network (MANET) is a category of ad-hoc network that can be reconfigurable its network. MANETS are self-organized networks, that can use the wireless links to connect various networks via mobile nodes: but it consumes more energy and it also has routing problems. This is the major drawback of being connected with the MANET technology. Therefore, this study proposes a new protocol as deep Q-learning network optimized with chaotic bat swarm optimization algorithm (CBS)-based optimized link state routing (OLSR) (CBS-OLSR) for MANET. This protocol reduces MANET energy usage and adopts OLSR multi-point relay (MPR) technology. MANET's OLSR and the CBS algorithm utilize a similar method to locate the best optimum path from source to destination node. By embedding the new improved deep Q-learning and OLSR algorithms, both are used for optimizing the MPR sets selection, it can efficiently diminish the energy consumption in the network topology, but automatically increase the lifespan of the network. It also enhances the package delivery ratio and decreases end-to-end delay. The experimental outcomes prove that the proposed protocol is reliable and proficient that is appropriate for numerous MANET applications.     

A virtual multiple message ferry backbone routing scheme for mobile ad-hoc networks

A MANET (Mobile Ad-Hoc Network) consists of relocating wireless communication devices without infrastructure installed in its network environment. Due to the mobility of the devices, the network topology changes frequently and consequently results in poor network performance. When the density of nodes in a MANET is sparse, the performance becomes even worse due to the intermittent connected routing problem arising. To cope with this problem, this paper integrates mechanisms of Virtual Multiple Message Ferry Routing (VMMFR) and Virtual Multiple Message Ferry Dispatch Scheduling (VMMFDS) into the routing protocol design of MANETs and proposes a Virtual Multiple Message Ferry Backbone Routing (VMMFBR) scheme for MANETs. Several simulations have been conducted using the network simulator NS-2 to evaluate the performance of the proposed VMMFR mechanism. Due to the VMMFR mechanism providing a reliable and predictable backbone routing for MANETs communications. The results show that the proposed method has a higher packet delivery ratio, low bandwidth consumed, and that there is greater precision of packet delivery time, compared to the traditional MANETs routing protocols (AOMDV and DSR). In addition, some theoretical results for the proposed VMMFDS mechanism to minimize the transfer waiting time are also given in this paper.     

Active detection in mitigating routing misbehavior for MANETs

Mobile ad hoc network (MANET) is vulnerable to security attacks because of the shared radio medium and lack of centralized coordination. Since most multi-hop routing protocols implicitly assume cooperative routing and are not originally designed for security attacks, MANET has been challenged by diverse denial-of-service attacks that often interfere with the protocol and interrupt on-going communication. In this paper, we propose an explore-based active detection scheme, called EBAD, to efficiently mitigate the routing misbehaviors in MANETs running with dynamic source routing. The basic idea is that a source node broadcasts a route request packet with a fictitious destination node to lure potential malicious nodes to reply a fake route reply packet. If the source node receives the fake route reply packet or an intermediate node cannot decrypt the received route reply packet, the routing misbehavior can be detected. We also propose a route expiry timer based approach to reduce the effect of route cache pollution because of the fake route reply. We present a simple analytical model of the EBAD and its numerical result in terms of detection rate. We also conduct extensive simulation experiments using the OMNeT++ for performance evaluation and comparison with the existing schemes, CBDS and 2ACK. The simulation results show that the proposed countermeasure can not only improve the detection rate and packet delivery ratio but also can reduce the energy consumption and detection latency.

     

Hybrid MANET–DTN and a New Algorithm for Relay Nodes Selection

In this paper, a new way to a selection of the secure relay nodes in hybrid MANET–DTN networks based on the cooperation between routing, trust and game theory mechanisms is introduced. The hybrid MANET–DTN enables delivering the data or messages in the situation when communication paths are disconnected or broken and also in the emergency situations. We focus on the situations when MANET routing protocol cannot establish the end-to-end connection between source and destination nodes. In this situation, it is necessary to select relay nodes, that will be able to transport data or messages between isolated islands of mobile terminals with limited connectivity to other terminals. The proposed algorithm enables to select the relay nodes, that will come into contact with other mobile nodes located in different network areas with regards to trust and game theory. The parameter trust is computed for all mobile nodes and relies on a parameter obtained during routing and data transport processes. The game theory provides a powerful tool to select one candidate from a number of possible nodes with respect to confidence and security. Moreover, we propose a new mechanism to compute and select the trusted node, that can be used for transportation of the secure data in this hostile and disconnected environment. In order to verify the functionalities of this mechanism, we implement this mechanism into the OPNET modeler simulation environment and introduce performance analysis.     

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.     

Energy and delay efficient dynamic cluster formation using hybrid AGA with FACO in EAACK MANETs

MANET is a set of mobile nodes which works in a dynamic changing network and it is capable of communicating with each other efficiently where all the nodes perform a dual role as that of a transmitter and a receiver. MANETs do not use any centralized administration for communication. The performance of a MANET can be further enhanced by adapting a cluster mechanism with the help of CEAACK to provide security from penetrators. In this paper we propose a new improved ant colony optimization algorithm with two strategies to reduce the overhead in communication by predicting mobility of node and cluster formation. Firstly, a dynamic mechanism is designed for determining one or more heuristic parameters for improving the performance of the MANET. Secondly a dynamic list of nodes are maintained which helps in forming clusters and electing the cluster head faster. In addition a dynamic broadcast approach algorithm is incorporated to provide the information about the status of the nodes to the hybrid fuzzy-ant colony algorithm. This approach ensures low maintenance cost and is expected to be robust against node failures and network topology changes. The positive outcome of these two techniques consumes low energy and in the process provides better efficiency in data transmission in MANETs. It also achieves correct delivery of packets without unnecessary delay.     

A survey of routing attacks in mobile ad hoc networks

Recently, mobile ad hoc networks became a hot research topic among researchers due to their flexibility and independence of network infrastructures, such as base stations. Due to unique characteristics, such as dynamic network topology, limited bandwidth, and limited battery power, routing in a MANET is a particularly challenging task compared to a conventional network. Early work in MANET research has mainly focused on developing an efficient routing mechanism in such a highly dynamic and resource-constrained network. At present, several efficient routing protocols have been proposed for MANET. Most of these protocols assume a trusted and cooperative environment. However, in the presence of malicious nodes, the networks are vulnerable to various kinds of attacks. In MANET, routing attacks are particularly serious. In this article, we investigate the state-of-the-art of security issues in MANET. In particular, we examine routing attacks, such as link spoofing and colluding misrelay attacks, as well as countermeasures against such attacks in existing MANET protocols.     

A secure and trust based on-demand multipath routing scheme for self-organized mobile ad-hoc networks

A mobile ad hoc network (MANET) is a self-configurable network connected by wireless links. This type of network is only suitable for provisional communication links as it is infrastructure-less and there is no centralized control. Providing QoS and security aware routing is a challenging task in this type of network due to dynamic topology and limited resources. The main purpose of secure and trust based on-demand multipath routing is to find trust based secure route from source to destination which will satisfy two or more end to end QoS constraints. In this paper, the standard ad hoc on-demand multi-path distance vector protocol is extended as the base routing protocol to evaluate this model. The proposed mesh based multipath routing scheme to discover all possible secure paths using secure adjacent position trust verification protocol and better link optimal path find by the Dolphin Echolocation Algorithm for efficient communication in MANET. The performance analysis and numerical results show that our proposed routing protocol produces better packet delivery ratio, reduced packet delay, reduced overheads and provide security against vulnerabilities and attacks.     

An energy aware algorithm for OLSR clustering

One of the important aspects of a mobile ad hoc network (MANET) is the limitation of the amount of available energy and the network lifetime. The tremendous amount of using mobile nodes in wireless communication medium makes energy efficiency a fundamental requirement for MANETs. In this paper, we propose a novel energy aware clustering algorithm for the optimized link state routing (OLSR) routing protocol. This algorithm takes into account the node density and mobility and gives major improvements regarding the number of elected cluster heads. Our objective is to elect a reasonable number of cluster heads that will serve for hierarchical routing based on OLSR. The proposed algorithm aims to increase the network lifetime by considering the ad hoc residual energy while taking routing decisions. It also optimizes the delay of carried flows by adopting a selective forwarding approach based on a hierarchical routing model.