HOLSR: a hierarchical proactive routing mechanism for mobile ad hoc networks

This article reviews the hierarchical optimized link state routing (HOLSR) mechanism for heterogeneous mobile ad hoc networks. In this work a heterogeneous mobile ad hoc network is defined as a network of mobile nodes that are characterized by different communications capabilities, such as multiple radio interfaces. The article focuses on proposing the HOLSR protocol. The HOLSR mechanism is derived from the OLSR protocol; however, unlike OLSR, the HOLSR protocol takes advantage of different mobile node capabilities to reduce the routing control overhead in large heterogeneous ad hoc networks, thus improving the performance of the routing mechanism.     

Multipath Security Aware Routing Protocol for MANET Based on Trust Enhanced Cluster Mechanism for Lossless Multimedia Data Transfer

The dynamic nature of mobile nodes of ad hoc network is mostly affected by security problems which reduce data forwarding rate in multimedia sources. Due to the rapid growth of wireless applications, the different multitalented routing protocols are proposed in recent years. But the recent protocols are not efficient for multimedia applications, till now, specific security aware routing protocols are not proposed for multimedia data transfers. In this paper, we proposed trust enhanced cluster based multipath routing (TECM) algorithm. We use energy efficient PSO algorithm used to create cluster formation and cluster head, super cluster head are selected from trust values, which compute form proposed TECM algorithm. The multi trust factors are used for trust computation, such as frame/packet loss ratio, frame/packet forward energy, frame/packet receiving energy, routing overhead, received signal strength, frame/packet forward rate, average forward delay and protocol deviation flag. We then combine proposed TECM algorithm with standard multipath OLSR protocol (TECM-OLSR) to analyze the performance of proposed algorithm. The simulated results show that proposed TECM-OLSR protocol is very effective in terms of loss and delivery rate, delay, routing overhead and network lifetime compare to FPNT-OLSR.     

A novel weighted clustering algorithm in mobile ad hoc networks using discrete particle swarm optimization (DPSOWCA)

In this paper, a novel weighted clustering algorithm in mobile ad hoc networks using discrete particle swarm optimization (DPSOWCA) is proposed. The proposed algorithm shows how discrete particle swarm optimization can be useful in enhancing the performance of clustering algorithms in mobile ad hoc networks. Consequently, it results in the minimum number of clusters and hence minimum cluster heads. The goals of the algorithm are to minimize the number of cluster heads, to enhance network stability, to maximize network lifetime, and to achieve good end‐to‐end performance. Analysis and simulation of the algorithm have been implemented and the validity of the algorithm has been proved. Results show that the proposed algorithm performs better than the existing weight‐based clustering algorithm and adapts to different kinds of network conditions. Copyright © 2009 John Wiley & Sons, Ltd.     

Performance Evaluation of Video Streaming Over Ad Hoc Networks Using Flat and Hierarchical Routing Protocols

A performance evaluation of real time services (such as video streaming) over mobile ad-hoc networks using both hierarchical and flat routing protocols is shown in this paper. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network have been simulated using NS-2. We use OLSR (Optimized Link State Protocol) as the flat routing protocol and our own implementation of HOLSR (Hierarchical OLSR)—which uses HNA (Host and Network Association) messages—as the hierarchical one, modifying other previous HOLSR version and maintaining the maximum compatibility with the flat OLSR. We carry out a complete comparison between these protocols focused on video evaluation. The simulation lets us compare the quality of service (QoS) of the video streaming paying attention to objective parameters (PSNR, packet delivery ratio, packet delay and interruptions). Some drawbacks of the hierarchical environment are also analyzed, as the link load between cluster heads and the lack of QoS-state-aware in HOLSR design. Quantitative results indicate that the protocol overhead is reduced (more than 40% in larger networks) and the video quality is improved (from 1 to 6 dB in certain cases) using hierarchical protocols.     

WRE‐OLSR,a new scheme for enhancing the lifetime within ad hoc and wireless sensor networks

Within ad hoc and wireless sensor networks, communications are accomplished in dynamic environments with a random movement of mobile devices. Thus, routing protocols over these networks are an important concern to offer efficient network scalability, manage topology information, and prolong the network lifetime. Optimized link state routing (OLSR) is one of those routing protocols implemented in ad hoc and wireless sensor networks. Because of its proactive technique, routes between two nodes are established in a very short time, but it can spend a lot of resources for selecting the multipoint relays (MPRs: nodes responsible for routing data) and exchanging topology control information. Thus, nodes playing for a long time a role of MPR within networks implementing such protocol can rapidly exhaust their batteries, which create route failures and affect the network lifetime. Our main approach relies on analyzing this concern by introducing a new criterion that implements a combination between the residual energy of a node and its reachability in order to determine the optimal number of MPRs and sustain the network lifetime. Simulations performed illustrate obviously that our approach is more significant compared with the basic heuristic used by original OLSR to compute the MPR set of a node.     

Improving mobile ad hoc network routing with satellite out‐of‐band signaling

Routing in mobile ad hoc networks is a complex task due to the mobility of the nodes and the constraints linked to a wireless multihop network (e.g., limited bandwidth, collisions, and bit errors). These adverse conditions impair not only data traffic but also routing signaling traffic, which feeds route computation. In this contribution, we propose to use satellite communications to help in the distribution of mobile ad hoc network routing signaling. The optimized link‐state routing (OLSR) is chosen among several routing protocols to be extended with satellite‐based signaling, yielding a version we call OLSR hybrid signaling (OLSR‐H). This new scheme is evaluated through simulations and yields improvements of approximately 10% in the data delivery ratio compared with a regular OLSR. This evaluation is conducted using two different network topology models, one being fit for representing forest firefighting operations. Copyright © 2013 John Wiley & Sons, Ltd.     

An energy efficient and QoS routing protocol for MANET realised over multi-objective red deer algorithm (RD-MOCER) in support of emergency disaster management

Terrorist attacks have contributed significantly to using wireless technologies to identify concrete destruction survivors. A dynamic ad hoc mobile network (MANET) consists of wireless linked nodes, which route hop-by-hop without the support of a fixed infrastructure acquires information from trapped survivors. The energy efficiency that extends the lifespan of the network is an essential prerequisite of MANET. Researchers have suggested many strategies to accomplish this purpose and a cluster of these techniques in MANETs are used to provide an energy-efficient approach. In this paper we are proposing a red deer multi-objective constraint applied for an energy efficient QoS routing (RD-MOCER) algorithm to the number of clusters in an ad hoc network and the energy dispensing in nodes to provide an energy effective solution and to minimise network traffic. Intracluster and intercluster traffic is handled by the cluster heads in the proposed approach. The algorithm suggested takes account of mobile nodes' node degrees, transmitting capacity and battery power usage. This approach gives a variety of options at a time, the key benefit of which is that the ideal Pareto front results in these solutions. We correlate the findings with two other well-known methods of clustering; MOPSO and MOEAQ-based clustering with different results. We conduct detailed simulations to demonstrate that the solution proposed is an effective and stronger solution to clustering in ad hoc cell networks than the other two techniques.     

基于图着色的无线自组网极小连通支配集算法

基于连通支配集算法的虚拟主干网技术对于无线自组网的路由优化、能量保护和资源分配都具有重要的作用。通过引入极大独立集和极小支配集概念,基于图着色思想提出一种新的适合于无线自组网的极小连通支配集算法,从理论上证明了该算法的正确性和高效性,也通过仿真实验分析了该算法在多种情况下的实际性能,仿真结果表明新算法在簇头和主干节点数目方面具有较好的性能,特别在节点密集的网络环境中更加突出。     

Reputation-Based Cooperative Detection Model of Selfish Nodes in Cluster-Based QoS-OLSR Protocol

The QOLSR is a multimedia protocol that was designed on top of the optimized link state routing (OLSR) protocol for mobile ad hoc network. It considers the quality of service (QoS) of the nodes during the selection of the multi-point relay (MPRs) nodes. One of the drawbacks of this protocol is the presence of selfish nodes that degrade the network lifetime. The limited energy and resources, and the absence of any motivation mechanism cause mobile nodes to behave selfishly during the MPRs selection. A new MPR selection based on cluster head election was proposed in previous work to increase network lifetime. In this paper, we consider the selfishness during the election and selection process by proposing the use of reputation system that will motivate nodes to participate during the selection of MPRs, where the reputation is calculated based on VCG mechanism design. After solving the selfishness during network formation, we have discovered that nodes can misbehave after being selected/elected. Such a passive malicious behavior could lead to a denial of service attack due to the drop of packets. As a solution, we propose a hierarchal cooperative watchdog detection model for the cluster-based QOLSR, where nodes cooperate in a hierarchical manner to detect selfish nodes. Moreover, to motivate watchdogs to monitor and cooperate with each other, incentives are given and calculated using cooperative game theory, where Shapley value is used to compute the contribution of each watchdog on the final decision. Simulation results show that the novel cluster-based QoS-OLSR model can give incentive to nodes to behave normally without sacrificing the quality of service of the network. In addition, the hierarchical cooperative detection model shows a more reliable and efficient detection of selfish nodes.     

An energy‐efficient clustering approach for collaborative data forwarding in heterogeneous MANET

Mobile ad hoc network consists of a group of mobile nodes that can communicate with each other without any infrastructure. Clustering of the mobile nodes ensures efficient use of available bandwidth and high network throughput. Various clustering schemes are developed to improve the energy efficiency and lifetime of the network. However, there is an increase in the energy consumption with the increase in the number of clusters for forwarding data. This paper presents an energy‐efficient clustering approach for collaborative data forwarding in mobile ad hoc network. The cluster head (CH) is selected based on the processing capability of the nodes and link connection metrics. The CH receives the data from the server and forwards the data to the member nodes at a corresponding data rate of the nodes. Data offloading technique manages the data traffic in the network. The CH rejoining approach enables load balancing in the network. The proposed clustering approach achieves a significant reduction in the energy consumption and data traffic and improvement in the throughput rate through stable routing.     

基于能量和密度的WSNs动态分区成簇路由算法

针对传统的层次型网络存在的分簇不合理和能耗不均衡等问题,提出了一种基于能量和密度的动态非均匀分区成簇路由算法。该算法先根据节点与基站之间的距离将网络合理地进行动态的区域划分,在区域内成簇,使靠近基站的簇规模小于距离基站较远的簇,减少靠近基站的簇首负担和能量消耗;通过综合考虑节点剩余能量和节点密度等因素来优化簇的非均匀划分和簇首的选择,簇首间采取基于数据聚合的多跳传输机制。仿真结果表明,与经典路由算法LEACH相比,该算法能有效均衡节点能耗,延长网络生命周期。     

An efficient routing protocol for the QoS support of large‐scale MANETs

The hierarchical routing algorithm is categorized as a kind of routing method using node clustering to create a hierarchical structure in large‐scale mobile ad hoc network (LMANET). In this paper, we proposed a new hierarchical clustering algorithm (HCAL) and a corresponded protocol for hierarchical routing in LMANET. The HCAL is designed based on a cost metric in the form of the link expiration time and node's relative degree. Correspondingly, the routing protocol for HCAL adopts a reactive protocol to control the existing cluster head (CH) nodes and handle proactive nodes to be considered as a cluster in LMANET. Hierarchical clustering algorithm jointly utilizes table‐driven and on‐demand routing by using a combined weight metric to search dominant set of nodes. This set is composed by link expiration time and node's relative degree to establish the intra/intercommunication paths in LMANET. The performance of the proposed algorithm and protocol is numerically evaluated in average end‐to‐end delay, number of CH per round, iteration count between the CHs, average CH keeping time, normalized routing overhead, and packet delivery ratio over a number of randomly generated benchmark scenarios. Furthermore, to corroborate the actual effectiveness of the HCAL algorithm, extensive performance comparisons are carried out with some state‐of‐the‐art routing algorithms, namely, Dynamic Doppler Velocity Clustering, Signal Characteristic‐Based Clustering, Dynamic Link Duration Clustering, and mobility‐based clustering algorithms.     

A new algorithm for cluster head selection in LEACH protocol for wireless sensor networks

In wireless sensor network, a large number of sensor nodes are distributed to cover a certain area. Sensor node is little in size with restricted processing power, memory, and limited battery life. Because of restricted battery power, wireless sensor network needs to broaden the system lifetime by reducing the energy consumption. A clustering‐based protocols adapt the use of energy by giving a balance to all nodes to become a cluster head. In this paper, we concentrate on a recent hierarchical routing protocols, which are depending on LEACH protocol to enhance its performance and increase the lifetime of wireless sensor network. So our enhanced protocol called Node Ranked–LEACH is proposed. Our proposed protocol improves the total network lifetime based on node rank algorithm. Node rank algorithm depends on both path cost and number of links between nodes to select the cluster head of each cluster. This enhancement reflects the real weight of specific node to success and can be represented as a cluster head. The proposed algorithm overcomes the random process selection, which leads to unexpected fail for some cluster heads in other LEACH versions, and it gives a good performance in the network lifetime and energy consumption comparing with previous version of LEACH protocols.     

基于无线信号不规则性的无线传感网层次型拓扑控制算法

构建层次型拓扑结构是延长网络生存时间的有效方法。该文将拓扑构建过程分为由簇成员组成的感知层和由簇头组成的平面数据转发层,建立了基于无线信号不规则性的网络能耗模型以及节点成簇稳定性模型,提出了基于无线信号不规则性的层次型拓扑控制(WSIBTC)算法。WSIBTC算法根据节点平均有效传输距离将监测区域划分为多个子区域,由成簇稳定性和节点在簇中的位置决定最终簇头,簇头间形成平面拓扑结构,延长网络生存时间。分析和仿真结果表明由WSIBTC算法得到的网络拓扑大幅度地提升了网络生存时间。     

Online Multicasting for Network Capacity Maximization in Energy-Constrained Ad Hoc Networks

In this paper, we present new algorithms for online multicast routing in ad hoc networks where nodes are energy-constrained. The objective is to maximize the total amount of multicast message data routed successfully over the network without any knowledge of future multicast request arrivals and generation rates. Specifically, we first propose an online algorithm for the problem based on an exponential function of energy utilization at each node. The competitive ratio of the proposed algorithm is analyzed if admission control of multicast requests is permitted. We then provide another online algorithm for the problem, which is based on minimizing transmission energy consumption for each multicast request and guaranteeing that the local network lifetime is no less than gamma times of the optimum, where gamma is constant with 0 < gammaleq 1. We finally conduct extensive experiments by simulations to analyze the performance of the proposed algorithms, in terms of network capacity, network lifetime, and transmission energy consumption for each multicast request. The experimental results clearly indicate that, for online multicast routing in ad hoc wireless networks, the network capacity is proportional to the network lifetime if the transmission energy consumption for each multicast request is at the same time minimized. This is in contrast to the implication by Kar et al. that the network lifetime is proportional to the network capacity when they considered the online unicast routing by devising an algorithm based on the exponential function of energy utilization at each node.     

A shared secret-based algorithm for securing the OLSR routing protocol

The strongest feature of ad hoc networks is its capability to be rapidly deployed anywhere and anytime without relying on a pre-existing infrastructure. From there, ad hoc networks offer the advantages to be auto-organized, ubiquitous, dynamic and completely autonomous. As a counter part, securing them becomes a more difficult task, especially because of the absence of centralized entities in the network. Inevitably, the security problem presents currently a hot topic raising more and more challenges within industrials and researchers, and many interesting securing solutions were meanwhile proposed, omitting however to suit to ad hoc networks characteristics and therefore disadvantaging them. In this paper, we propose a securing scheme for the OLSR routing protocol based on the secret sharing idea. We initially expose the general characteristics and the security problems related to ad hoc routing protocols. We then address the security requirements of ad hoc routing protocols and the security requirements we focus on. Finally, we define our completely and distributed securing algorithm based on threshold cryptography. A primary main conception objective being to suit as much as possible to ad hoc networks characteristics by avoiding as much as possible assumptions contradictory with the auto-organized and dynamic nature of ad hoc networks. Simulation results depict the additional delay due to security enhancements. Results show that this delay stills suitable to OLSR routing specifications.     

面向高动态移动自组织网络的生物启发分簇算法

分簇可以有效地提高大规模移动自组织网络的性能.但高动态的移动自组织网络具有节点移动性强、网络拓扑变化快的特点,应用传统的分簇算法会造成网络性能迅速下降,频繁的簇拓扑更新造成了簇结构的不稳定和控制开销的增加.为了解决传统分簇算法无法适应高动态的大规模移动自组织网络的问题,提出了一种基于生物启发的移动感知分簇算法,该算法对多头绒泡菌的觅食模型进行了改进,使其适用于移动自组织网络领域.由于该算法与节点的移动特性进行了结合,所以该算法可以有效地在高动态移动自组织网络中进行簇的建立与维护.实验结果表明,相较于其他传统分簇算法,本文算法提高了平均链路连接保持时间和平均簇首保持时间,使得簇结构更加稳定,提高了对高动态、大规模移动自组织网络的适应能力.     

A load balancing energy efficient clustering algorithm for MANETs

Nodes in mobile ad hoc Networks (MANETs) are characterized by their limited resources. Hence, the concept of clustering was introduced to allow spacial reuse of bandwidth and to minimize routing overhead. However, node mobility perturbs the stability of the network and affects the performance of other protocols such as scheduling, routing, and resource allocation, which makes re‐clustering the network to maintain up‐to‐date information at each node unavoidable. Consequently, clustering models for MANETS should be carefully designed while taking into consideration the fact that mobile nodes are energy constrained. In this paper, we propose a dynamic energy‐efficient clustering algorithm that prolongs the network lifetime by electing cluster‐heads taking into consideration, in addition to other parameters such as mobility, their residual energies and making them dynamically monitor their energy consumption to either diminish the number of their cluster‐members or relinquish their roles. We have evaluated the performance of the proposed clustering model and compared it with other related clustering approaches found in the literature. Obtained results show the efficiency of the proposed algorithm. Copyright © 2010 John Wiley & Sons, Ltd.     

Maximizing the Network Life Time Based on Energy Efficient Routing in Ad Hoc Networks

The maximization of a networks lifetime is an important part of research in the present scenario. In an ad hoc network, the topology of network changes frequently due to the mobility of mobile nodes where the communication is possible without any network infrastructure. Mobile nodes have limited energy resources so that the energy efficient routing should be provided which increases the life time of the network. The existing routing mechanisms do not consider energy of nodes for data transmission. In this paper the data transfer from source to destination is based on the minimum hop count and residual energy of the mobile nodes. The analysis is carried out by using the network simulator. The simulation results shows that the proposed work provides an energy efficient routing in ad hoc networks.

     

Integrating Mobile Ad Hoc Network to the Internet

A novel scheme is presented to integrate mobile ad hoc networks （MANETs） with the lnternet and support mobility across wireless local area networks （WLANs） and MANETs. The mobile nodes, connected as a MANET, employ the optimize d link state routing （OLSR） protocol for routing within the MANET. Mobility management across WLANs and MANETs is achieved through the hierarchical mobile IPv6 （HMIPv6） protocol. The performance is evaluated on a HMIPv6 based test-bed composed of WLANs and MANETs. The efficiency gain obtained from using HMIPv6 in such a hybrid network is investigated. The investigation result shows that the use of HMIPv6 can achieve up to 27% gain on reducing the handoff latency when a mobile roams within a domain. Concerning the reduction of the signaling load on the lnternet, the use of HMIPv6 can achieve at least a 54% gain and converges to 69%.