Performance Evaluation of Routing Protocols for Ad Hoc Wireless Networks

A mobile ad hoc network is a collection of autonomous mobile nodes that communicate with each other over wireless links. Such networks are expected to play an increasingly important role in future civilian and military settings, being useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable and movement of communicating parties is possible. However, since there is no stationary infrastructure such as base stations, mobile hosts need to operate as routers in order to maintain the information about the network connectivity. Therefore, a number of routing protocols have been proposed for ad hoc wireless networks. In this paper, we study and compare the performance of the following routing protocols AODV, PAODV (preemptive AODV), CBRP, DSR, and DSDV. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network were simulated. Our results indicate that despite its improvement in reducing route request packets, CBRP has a higher overhead than DSR because of its periodic hello messages while AODV's end-to-end packet delay is the shortest when compared to DSR and CBRP. PAODV has shown little improvements over AODV.     

Ad Hoc网络路由协议研究及其性能比较

介绍和分析了当前Ad Hoc网络中的主要路由协议算法,在Linux下使用网络仿真软件NS2评价Ad Hoc路由协议中的距离矢量路由协议、临时排序路由算法、动态源路由协议和Ad Hoc按需距离矢量路由协议,编写了用于仿真实现的脚本程序,并对仿真结果进行了分析比较和性能评价,由此得出不同协议的特性及其适用范围。     

ECBRP: An Efficient Cluster-Based Routing Protocol for Real-Time Multimedia Streaming in MANETs

The dynamic characteristics of wireless networks and stringent QoS requirements of multimedia applications identify significant challenges for providing QoS guarantees for real-time multimedia streaming in such wireless environment. QoS routing protocols can decisively contribute to the QoS provision of network systems. This paper proposes an efficient cluster-based routing protocol (ECBRP) for real-time multimedia streaming in mobile ad hoc networks. First, to improve the stability of clusterheads, we introduce a new algorithm of cluster formation, in consideration of the node mobility and connectivity. Second, a link-broken detection mechanism is designed, which is able to distinguish whether packet loss is due to mobility or congestion, and to make proper reaction. This mechanism contributes to reduce route overhead, and to increase the decodable ratio of video frame at the application layer as well. Third, the routing protocol is enhanced via an adaptive packet salvage strategy, in order to alleviate the congestion in consideration of the characteristics of multimedia traffic. Our simulation experiment results demonstrate that the ECBRP leads to more stable cluster formation than the CBRP, and 80% decreases in the frequency of clusterhead changes against CBRP. As a result, the quality of real-time multimedia streaming is improved significantly, in terms of decodable frame ratio, delay and delay jitter, etc.     

Ad Hoc网络中两种按需路由协议的比较

Ad hoc网络的特征是多跳的无线连接，网络拓扑的频繁变化，以及需要有效的动态路由协议。重点比较Ad hoc网络中两种主要的按需路由协议：动态源路由（DSR）协议和Ad hoc按需距离矢量路由（AODV）协议。尽管DSR和AODV都是按需路由协议，但不同的协议机制导致了网络性能的显著差异。在OPNET仿真平台下，对采用不用路由协议的网络时延和吞吐量进行比较，从而分析不同的路由机制引起的网络性能差异。     

一种基于AODV路由协议的分簇算法研究

基于距离向量的按需路由协议AODV是AdHoc网络研究的热点之一。该协议有效减少了建立和维护路由所需要的开支,但是随着网络节点发送数据量的增加,网络性能会迅速下降。为了提高AdHoc网络的路由效率和可靠性,文章提出了一种基于AODV路由协议的分簇算法。经仿真研究分析表明,该算法提高了网络节点的平均每跳吞吐率,减少了节点的平均每跳时延。     

无线Mesh网路由协议仿真及性能分析

当前对无线网格网络（Mesh网络）主要研究之一是无线路由技术,即针对无线Mesh网络自身的特点进行路由设计。在熟悉基于Linux平台的网络仿真器（NS2）针对Mesh网络路由协议的仿真过程的基础上,利用NS2网络仿真软件分别从端到端平均时延、分组递交率、归一化路由开销三个方面比较了目前三种典型的路由协议——按需平面距离矢量路由（AODV）、动态源路由（DSR）和目的序列距离矢量路由（DSDV）的性能,并详细介绍了整个仿真过程的步骤。最后,通过分析AODV协议的吞吐量,得出网络最佳容纳的节点数,研究成果对协议的实现具有重要的应用价值。     

无线Ad hoc网络机会路由的实现与仿真

在无线自组织网络中,路由协议对网络的性能起着关键性作用。然而由于无线信道的不稳定性经常造成通信中断而需重建路由,使自组织网传统路由协议的效率大大降低。提出了一种应用于无线自组织网络的机会路由协议（WAOR）,利用无线信道的广播特性和多径传输来增强链路的可靠性。采用网络仿真器NS2的仿真结果表明,WAOR的性能优于传统的动态源路由协议（DSR）和自组织网按需平面距离矢量路由协议（AODV）。     

移动自组织网络预测分簇算法的路由协议

针对移动自组织网络中传统分簇算法存在稳定性低、网络开销大的问题,在WCA分簇算法的基础上,提出一种带有预测机制的EWCA-MP(Efficient on-demand Weighted Clustering Algorithm using Mobility Prediction)分簇算法,该算法在簇头选择时充分考虑节点间的链路保持时间,在簇维护阶段引入模糊逻辑的概念,对Hello消息包的广播周期进行优化。并将其应用于CBRP中,提出了一种ECBRP-MP(Efficient Cluster Based Routing Protocol using Mobility Prediction)移动预测的分簇路由协议。仿真结果表明,EWCA-MP算法在簇头数目、单位时间内节点转移次数和统治集更新次数明显减少,ECBRP-MP路由协议在路由开销、分组投递率的性能得到优化。     

基于NS2的Ad hoc网络路由协议性能分析比较

A d Hoc网络的路由协议是A d Hoc网络研究的关键问题,对于研究A d Hoc网络是至关重要的。本文采用网络仿真软件N S2评价移动自组网的路由协议。通过实例仿真,利用编写的脚本程序,对仿真结果进行分析,从而对移动自组网路由协议AODV(自组网按需路由协议)、DSR(动态源路由)以及DSDV(基于目的序号和距离矢量路由)的性能参数进行比较。     

Survey on cluster-based routing protocols for cognitive radio sensor networks

Routing protocols could achieve efficient convergecast transmission of sensed data in cognitive radio sensor network (CRSN),and it is of vital importance for the whole network performance.In particular,cluster-based routing protocols could further lower routing selection complexity and improve scalability.Therefore,an overview of cluster-based routing protocols for CRSN was provided.Firstly,after a brief introduction to the concept and advantages of clustering in CRSN,the major factors concerning clustering algorithm design were pointed out.Secondly,the challenges faced by routing protocol design in CRSN and basic design principles were explored.Thirdly,the previous work of cluster-based routing protocols for CRSN was systematically analyzed and summarized.Finally,issues that require urgent solutions and future research directions were suggested.     

多跳无线Ad hoc网络路由协议的模拟和性能比较

文中采用随机场景的模拟方法对3种多跳无线Ad hoc网络路由协议的性能做了定量性的分析.对网络模拟器NS-2做了更进一步的拓展:增加SASR路由协议、增加AODV的MAC层虚拟HELLO机制,在此基础上对路由协议AODV,DSR和SASR进行了模拟.模拟结果显示:3种路由协议都能适应网络的拓扑结构变化,但是SASR和AODV路由协议在多跳无线Ad Hoc网络仍然具有相对的优越性.     

MANET Routing with Provably Low Complexity Through Constant Density Clustering and Route Request Broadcast

As mobile ad hoc networks (MANETs) are emerging as important components in critical and large-scale applications, it is crucial to develop MANET routing mechanisms with provably low complexity. In this paper, we give a tutorial overview of the efficient use of elementary node clustering and route request broadcast mechanisms for low-complexity MANET routing. We explain these mechanisms with illustrative examples and discuss their theoretical performance characteristics. We demonstrate that node clustering with constant density and route request broadcasting with a doubling radius technique over the network of cluster leaders can be employed for MANET routing with theoretically proven low complexity. Moreover, we contrast these efficient elementary clustering and route request broadcast mechanisms with clustering and route information accumulation mechanisms in the widely studied AODV and DSR routing protocols and discuss the implications of these various mechanisms for scalable MANET routing.     

AODV routing overhead analysis based on link failure probability in MANET

This article puts forward an Ad-hoc on-demand distance vector routing(AODV)routing overhead analysis method in mobile Ad-hoc network(MANET).Although multiple routing protocols have been proposed to improve the performance,scarcely any paper analyzed the routing overhead caused by routing setup and maintenance processes in mathematical way.Routing overhead consumes part of network resources and limits the supported traffic in the network.For on-demand routing protocols like AODV,the routing overhead depends on the link failure probability to a great extent.This article analyzes the collision probability caused by hidden-node problem and the impact on link failure probability.In chain and rectangle scenarios,it presents a mathematical analysis of the theoretical routing overhead of AODV protocol based on link failure probability.Simulations on OPNET 14.5platform match well with the theoretical derivation which confirms the effectiveness of the analysis method.     

Ad hoc网络两种按需路由协议性能分析

Ad hoc网络是一种无需依赖于事先布设的基础设施,而仅依靠网络内部节点之间的协作,就能够完成节点间通信的网络。比较了Ad hoc网络两种主流的按需路由协议：动态源路由协议,自组网按需距离矢量路由协议。使用基于ns-2的仿真模型进行仿真,并通过分组交付率、平均端到端时延、标准化路由负荷、对两种按需路由协议进行评估。实验结果表明即使DSR和AODV协议都是按需路由协议,但它们采取的路由机制的不同,导致它们的性能表现的巨大差异。     

一种无线传感器网路由算法的设计与实现

讨论了无线传感器网络的特殊性,分析了其路由算法的需求。借鉴Ad Hoc网中比较成熟的AODV(Ad Hoc按需平面距离矢量)协议和DSR(动态源路由)协议,采用了按需驱动的路由策略,优化了路由建立和维护算法,提出了RODR(简化的按需路由)协议。采用该路由算法的网络协议已在由ATmega128L微处理器和CC2420构成的节点机上实现,通过组网实验,初步验证了其可行性。     

A cluster-based trust-aware routing protocol for mobile ad hoc networks

Routing protocols are the binding force in mobile ad hoc network (MANETs) since they facilitate communication beyond the wireless transmission range of the nodes. However, the infrastructure-less, pervasive, and distributed nature of MANETs renders them vulnerable to security threats. In this paper, we propose a novel cluster-based trust-aware routing protocol (CBTRP) for MANETs to protect forwarded packets from intermediary malicious nodes. The proposed protocol organizes the network into one-hop disjoint clusters then elects the most qualified and trustworthy nodes to play the role of cluster-heads that are responsible for handling all the routing activities. The proposed CBTRP continuously ensures the trustworthiness of cluster-heads by replacing them as soon as they become malicious and can dynamically update the packet path to avoid malicious routes. We have implemented and simulated the proposed protocol then evaluated its performance compared to the clustered based routing protocol (CBRP) as well as the 2ACK approach. Comparisons and analysis have shown the effectiveness of our proposed scheme.     

A Scalable-Adaptive Snack Routing Strategy (SRS) for Semi-Administrated Mobile Ad Hoc Networks (SAMANETs)

Recently, Mobile Ad Hoc networks (MANETs) are growing in popularity and importance. They present a possible communication among a set of mobile nodes with no need for either a pre-established infrastructure or a central administration. However, in order to guarantee an efficient communication among network nodes, efficient routing algorithms should be established. Routing plays the central role in providing ubiquitous network communications services in such dynamic networks. The problem is further aggravated through the node mobility as any node may move at any time without notice. Several routing protocols had been proposed; however, most of them suffer from control packet flooding, which results in a scalability problem. In this paper, a new routing strategy for MANETs is proposed which is called Snack Routing Strategy (SRS). The basic idea of SRS is to continuously inform the network mobile nodes with any changes in the network topology without overloading the network by a huge amount of control messages. SRS is a hybrid routing strategy that relies on Learning by accumulation, hence, new routes can be discovered by learning the accumulative data stored in the nodes routing tables by several foraging artificial snacks. SRS uses no periodic routing advertisement messages but uses artificial snacks instead, thereby reducing the network bandwidth overhead and minimizing end-to-end transmission delay. SRS has been compared against two well known protocols AODV and DSR. Experimental results have shown that SRS outperforms both AODV and DSR as it introduces the minimal routing overheads.     

基于NS2的AODV/DSR Ad Hoc路由协议的性能分析

分析了DSR和AODV两种Ad Hoc典型路由协议的原理和性能,介绍了仿真软件NS2.最后在NS2平台上进行了仿真.仿真结果表明,在动态拓扑变化、网络负载比较大的情况下,AODV性能明显优于DSR路由协议.     

DOA: DSR over AODV Routing for Mobile Ad Hoc Networks

We present a lightweight hierarchical routing model, Way Point Routing (WPR), in which a number of intermediate nodes on a route are selected as waypoints and the route is divided into segments by the waypoints. Waypoints, including the source and the destination, run a high-level intersegment routing protocol, while the nodes on each segment run a low-level intrasegment routing protocol. One distinct advantage of our model is that when a node on the route moves out or fails, instead of discarding the whole original route and discovering a new route from the source to the destination, only the two waypoint nodes of the broken segment have to find a new segment. In addition, our model is lightweight because it maintains a hierarchy only for nodes on active routes. On the other hand, existing hierarchical routing protocols such as CGSR and ZRP maintain hierarchies for the entire network. We present an instantiation of WPR, where we use DSR as the intersegment routing protocol and AODV as the intrasegment routing protocol. This instantiation is termed DSR over AODV (DOA) routing protocol. Thus, DSR and AODV—two well-known on-demand routing protocols for MANETs—are combined into one hierarchical routing protocol and become two special cases of our protocol. Furthermore, we present two novel techniques for DOA: one is an efficient loop detection method and the other is a multitarget route discovery. Simulation results show that DOA scales well for large networks with more than 1,000 nodes, incurring about 60 percent-80 percent less overhead than AODV, while other metrics are better than or comparable to AODV and DSR.     

Multihop sensor network design for wide-band communications

This paper presents a master/slave cellular-based mobile ad hoc network architecture for multihop multimedia communications. The proposed network is based on a new paradigm for solving the problem of cluster-based ad hoc routing when utilizing existing wireless local area network (WLAN) technologies. The network architecture is a mixture of two different types of networks: infrastructure (master-and-slave) and ad hoc. In this architecture, the participating slave nodes (SNs) in each cluster communicate with each other via their respective master nodes (MNs) in an infrastructure network. In contrast to traditional cellular networks where the base stations are fixed (e.g., interconnected via a wired backbone), in this network the MNs (e.g., base stations) are mobile; thus, interconnection is accomplished dynamically and in an ad hoc manner. For network implementation, the IEEE 802.11 WLAN has been deployed. Since there is no stationary node in this network, all the nodes in a cluster may have to move together as a group. However, in order to allow a mobile node to move to another cluster, which requires changing its point of attachment, a handoff process utilizing Mobile IP version 6 (IPv6) has been considered. For ad hoc routing between the master nodes (i.e., MNs), the Ad hoc On-demand Distance Vector (AODV) Routing protocol has been deployed. In assessing the network performance, field test trials have been carried out to measure the proposed network performance. These measurements include packet loss, delays under various test conditions such as a change of ad hoc route, handoffs, etc.