基于节点能量策略的AOMDV路由算法改进

通过对AOMDV多径协议进行改进,提出了一种基于节点剩余能量策略MMBCR的多径协议(EAOMDV)。改进协议以节点剩余能量为备份路径的度量对AOMDV多径协议进行改进。使用NS2软件进行仿真,通过改变节点的暂停时间来比较EAOMDV协议和AOMDV协议的性能。仿真结果表明,与AOMDV多径协议相比,新协议路由开销和丢包率有所增加,但降低了网络的总能耗并减少了某时刻耗尽能量的节点数目,从而延长了网络的存活时间。     

An adaptive‐aware energy and queue improvement of AOMDV

Because the node energy and network resources in the wireless sensor network (WSN) are very finite, it is necessary to distribute data traffic reasonably and achieve network load balancing. Ad hoc on‐demand multipath distance vector (AOMDV) is a widely used routing protocol in WSN, but it has some deficiencies: establishes the route by only using hop counts as the routing criterion without considering other factors such as energy consumption and network load; forwards route request in fixed delay resulting in building the nonoptimal path; and cannot update the path status after built paths. For the deficiency of AOMDV, this paper proposes a multipath routing protocol adaptive energy and queue AOMDV (AEQAOMDV) based on adaptively sensing node residual energy and buffer queue length. When sending a routing request, the forwarding delay of the routing request is adaptively adjusted by both the residual energy and the queue length of the intermediate node; when establishing routes, a fitness is defined as a routing criterion according to the link energy and the queue load, predicting the available duration of the node based on the energy consumption rate and adjusting the weight of the routing criterion by the available duration of the node; after the routes are established, the path information status are updated via periodically broadcasting Hello that carries the path information with the minimum fitness, making the source node update the path information periodically. By using NS‐2, simulations demonstrate that compared with AOMDV, AEQAOMDV has obvious improvements in increasing packet delivery ratio, reducing network routing overhead, reducing route discovery frequency, and decreasing the network delay. And AEQAOMDV is more suitable for WSN.     

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.     

IM2PR: interference-minimized multipath routing protocol for wireless sensor networks

With respect to the inherent advantages of multipath routing, nowadays multipath routing is known as an efficient mechanism to provide even network resource utilization and efficient data transmission in different networks. In this context, several multipath routing protocols have been developed over the past years. However, due to the time-varying characteristics of low-power wireless communications and broadcast nature of radio channel, performance benefits of traffic distribution over multiple paths in wireless sensor networks are less obvious. Motivated by the drawbacks of the existing multipath routing protocols, this paper presents an Interference-Minimized MultiPath Routing protocol (IM2PR) which aims to discover a sufficient number of minimum interfering paths with high data transmission quality between each event area and sink node in order to provide efficient event data packet forwarding in event-driven wireless sensor networks. Extensive performance evaluations show that IM2PR presents improvements over the Micro Sensor Multipath Routing Protocol and Energy-Efficient data Routing Protocol as follows: 50 and 70 % in term of packet reception ratio at the sink, 44 and 80 % in term of goodput, 33 and 40 % in term of packet delivery latency, 40 and 57 % in term of energy consumption, 50 and 60 % in term of packet delivery overhead.     

Load balancing maximal minimal nodal residual energy ad hoc on-demand multipath distance vector routing protocol (LBMMRE-AOMDV)

Mobile ad hoc multipath routing protocols have attracted considerable research attention over the past decade, but the limited battery life of nodes remains a significant obstacle. Many researchers have designed multipath routing protocols that balance the data load between the generated paths, but there is always some tradeoff between conserving the nodes’ energy and delivering data. In this paper, I introduce a load balancing (LB) multipath routing protocol based on maximal minimal nodal residual energy (MMRE) in the ad hoc on-demand multipath distance vector (AOMDV) protocol. The proposed LBMMRE-AOMDV protocol evaluates the generated paths based on the maximal nodal residual energy and the actual number of packets that could be transmitted over that path without depleting the nodes’ energy. The performance of the proposed protocol was tested and evaluated using different scenarios and performance metrics, and achieved good results compared with MMRE-AOMDV and AOMDV. In particular, the proposed method can increase packet delivery and decrease the number of dead nodes, thus reducing the probability of network portioning.     

移动自组网AOMDV协议应对衰落改进方案

在移动自组网中,信道条件直接决定了数据包传输的可靠性.为有效应对信道衰落,提出一种基于信道状态、可实时监控链路的路由方案来改进AOMDV协议.该方案在路由寻找过程中,以信道平均无衰时间（ANFD）作为路由度量来选择稳定的链路,并采用一种根据信道状态信息抢先切换的策略来维护连接的可靠性.仿真结果表明,通过该改进方案,AOMDV协议在网络吞吐量、平均端到端时延、路由控制开销和数据包投递率等性能上均有改善.     

Effectiveness of Reliable Routing Protocols in Mobile Ad Hoc Networks

Due to unpredictable topology change and frequent link failure, it becomes evident major challenge to provide the stable route between source and destination in mobile ad hoc networks. Unlike previous multipath routing schemes for redundancy and unicast routing protocol utilizing the longest route expiration time measured by geographical information supported by Global Positioning System (GPS), we develop a framework to establish the most stable route based on measured frequency of link failure, available battery as well as the number of actual connections. To evaluate performance of proposed scheme, we provide practical simulation results for multipath and unicast routing protocol in terms of packet delivery ratio, control overhead, average hop length as well as end-to-end delay. Through analysis of simulation results, we demonstrate that our scheme shows better performance than general unicast routing protocol as well as similar packet delivery ratio to multipath routing protocol with less maintenance overhead. Ki-Il Kim received the M.S. and Ph.D. degrees in computer science from the Chungnam National University, Daejeon, Korea, in 2002 and 2005, respectively. He is currently with Department of Information Science, Gyeongsang National University as a faculty member. His research interests include routing for MANET, QoS in wireless network, multicast, and sensor networks. Sang-Ha Kim received the B.S. degree in chemistry from Seoul National University, Seoul, Korea, in 1980. He received the M.S. and Ph.D. degrees in quantum scattering and computer science from the University of Houston, Houston, TX, in 1984 and 1989, respectively. From 1990 to 1991, he was with the Supercomputing Center, SERI, Korean Institute of Science and Technology (KIST) as Senior Researcher. He joined Chungnam National University, Daejeon, Korea, in 1992, where he is a Professor. His current research interests include wireless networks, ad hoc networks, QoS, optical networks, and network analysis.     

Ring Mesh Based Multicast Routing Scheme in MANET Using Bandwidth Delay Product

Quality of Service (QoS) support in Mobile Ad Hoc Networks (MANETs) for group communication necessitates design of reliable networks with multicast support mechanisms. Reliable network connectivity among MANET nodes require high quality links that have much less packet drops and reliable nodes considering node mobility and failures. Reliability of a network can be enhanced by designing an end-to-end network pipe that satisfies the required QoS in terms of in-flight packets from source to a destination as well as by using a path comprising of reliable nodes. In-flight packets may be computed by using bandwidth delay product (BDP) of a network pipe. To meet the QoS requirements of an application, BDP should be maintained stable irrespective of vibrant network conditions. In this paper, we propose a BDP based multicast routing scheme in MANET using reliable ring mesh backbone. The scheme operates in the following sequence. (1) Reliable node pairs are computed based on mobility, remaining battery power and differential signal strength. The node pairs also compute BDP between them. BDP of a reliability pair is assessed using available bandwidth and delay experienced by a packet between them. (2) Backbone ring mesh is constructed using reliable pair nodes and convex hull algorithm. Reliable ring mesh is constructed at an arbitrary distance from the centroid of the MANET area. (3) Multicast paths are found by discovering a path from source to each destination of the group with concatenated set of reliability pairs that satisfy the BDP requirement. (4) The ring mesh maintains high BDP on ring links and can recover in case of node mobility and failures. Results show that there is an improvement in terms of end-to-end delay, packet delivery ratio, control overhead, memory overhead and application rejection ratio as compared to the Enhanced On Demand Multicast Routing Protocol.     

An Extended Dynamic Source Routing Scheme in Ad Hoc Wireless Networks

In this paper we consider a multipath extension to the dynamic source routing (DSR) protocol proposed by Johnson and Maltz, an on-demand routing protocol for ad hoc wireless networks. This extension keeps two node-disjoint paths between the source and destination of a routing process without introducing extra overhead. Unlike other multipath extensions where node-disjoint paths are selected at the destination or at the reply phase, our approach generates two node-disjoint paths during the query phase of the route discovery process by restricting the way the query packet is flooded. Several optimization options are also considered. Simulation is conducted to determine the success rate of finding node-disjoint paths.     

Improving protocol robustness in ad hoc networks through cooperative packet caching and shortest multipath routing

A mobile ad hoc network is an autonomous system of infrastructure-less, multihop, wireless mobile nodes. Reactive routing protocols perform well in this environment due to their ability to cope quickly against topological changes. This paper proposes a new routing protocol named CHAMP (caching and multiple path) routing protocol. CHAMP uses cooperative packet caching and shortest multipath routing to reduce packet loss due to frequent route failures. We show through extensive simulation results that these two techniques yield significant improvement in terms of packet delivery, end-to-end delay and routing overhead. We also show that existing protocol optimizations employed to reduce packet loss due to frequent route failures, namely local repair in AODV and packet salvaging in DSR, are not effective at high mobility rates and high network traffic.     

无线传感器网络路由协议的设计与实现

针对传统路由协议端到端时延长、丢包率过高的现实问题,提出了一种基于贪婪转发的能量感知多路径路由协议(Greedy Forward Energy-aware Multipath Routing Protocol,GFEMRP)。GFEMRP从传感器起始结点出发,如果遇到网络黑洞则选择周边转发方式,否则将选择吞吐量大、且更接近于目的结点的结点作为下一跳结点。利用了OMNET++5.0和INET框架对包括无线自组网按需平面距离向量路由协议(Ad hoc on-demand distance vector routing protocol,AODV),动态按需无线自组织网络(Dynamic MANET On-demand,DYMO),贪婪周边无状态路由无线网络(Greedy Perimeter Stateless Routing for Wireless Networks,GPSR)和GFEMRP协议在内的四种路由协议进行了仿真和比较,实验结果表明GFEMRP协议具有良好的端到端时延、丢包率等性能。     

A gradient‐based multiple‐path routing protocol for low duty‐cycled wireless sensor networks

Routing in a low duty‐cycled wireless sensor network (WSN) has attracted much attention recently because of the challenge that low duty‐cycled sleep scheduling brings to the design of efficient distributed routing protocols for such networks. In a low duty‐cycled WSN, a big problem is how to design an efficient distributed routing protocol, which uses only local network state information while achieving low end‐to‐end (E2E) packet delivery delay and also high packet delivery efficiency. In this paper, we study low duty‐cycled WSNs wherein sensor nodes adopt pseudorandom sleep scheduling for energy saving. The objective of this paper is to design an efficient distributed routing protocol with low overhead. For this purpose, we design a simple but efficient hop‐by‐hop routing protocol, which integrates the ideas of multipath routing and gradient‐based routing for improved routing performance. We conduct extensive simulations, and the results demonstrate the high performance of the proposed protocol in terms of E2E packet delivery latency and packet delivery efficiency as compared with existing protocols. Copyright © 2014 John Wiley & Sons, Ltd.     

IP网络时延敏感型业务流自适应负载均衡算法

互联网对时延敏感的业务数据流,要求具有较低的端到端时延,但是网络拥塞的发生,将会使服务质量无法保证。基于链路关键度提出了一种新的自适应负载均衡路由算法(LARA,load adaptive routing algorithm),能最大限度地避开拥塞链路从而减少端到端延迟。该算法通过得到一个优化目标函数,并利用凸优化理论将优化目标函数分解为若干个子函数,最终得到一个简单的分布式协议。利用NS2仿真器在基于CERNET2真实的拓扑结构上进行仿真实验,同时与网络中能普遍部署的等开销多路径(ECMP,equal-costmulti-path)算法相比较,通过测试反馈时延、分组丢失率、流量负载,结果表明LARA具有更好的自适应性和健壮性,性能相比更优。     

Collaboration of Trusted Node and QoS Based Energy Multi Path Routing Protocol for Vehicular Ad Hoc Networks

In the recent past information transmission through the vehicular ad hoc network (VANET) playing a vital role due to increase in accident statistics. There are numerous networking and VANET protocols helpful to control the trust while transmitting the data from source to destination nodes in traffic environment. In spite of many existing protocols for analyzing the trust in the network, the challenge of routing overhead, high energy consumption and malicious attacks issues still continue in the communication. This research introduces the trust collaboration nodes and Quality of Service (QoS) with energy multipath routing protocol for transmitting the information through VANET. Initially, the trusted nodes have been collected for analyzing the neighbouring nodes and the information are transmitted using the proposed QoS based energy efficient multipath routing protocol. During this transmission, the multi path protocol eliminates the intermediate attacks effectively when compared with the other existing protocols. The Proposed protocol maintains the QoS while routing the information from source to destination and further the efficiency has been analyzed through simulation experiments and Montgomery multiplier based Elliptic Curve Cryptography (ECC) will be used in future for better security and privacy.     

Ant-based routing and QoS-effective data collection for mobile wireless sensor network

Mobility management in mobile wireless sensor networks (MWSNs) is a complex problem that must be taken into account. In MWSN, nodes move in and out of the network randomly. Hence, a path formed between two distant nodes is highly susceptible to changes due to unpredictable node movement. Also, due to the limited resources in WSN, the paths used for data transmission must be tested for the link quality and time consumed for data forwarding. In order to solve these issues, in this paper, an ant-based routing protocol with QoS-effective data collection mechanism is proposed. In this protocol, the link quality and link delay are estimated for each pair of nodes. Link quality is estimated in terms of packet reception rate, received signal strength indicator, and link quality index. A reliable path is chosen from the source to the destination based on the paths traversed by forward ants and backward ants. Then, if the link is found to be defective during data transmission, a link reinforcement technique is used to deliver the data packet at the destination successfully. The mobile robots collect the information with high data utility. In addition, each mobile robot is equipped with multiple antennas, and space division multiple access technique is then applied for effective data collection from multiple mobile robots. Simulation results show that the proposed routing protocol provides reliability by reducing the packet drop and end-to-end delay when compared to the existing protocols.     

Route Stability Based QoS Routing in Mobile Ad Hoc Networks

To provide high quality communications service among mobile wireless devices is basically a challenging task in wireless ad hoc networks. In this paper, we propose a Route Stability based QoS Routing (RSQR) protocol in Mobile Ad Hoc Networks (MANETs) which is an extension of QoS routing with throughput and delay constraints. Ensuring a data path to be valid for sufficiently longer period of time is a very difficult problem in MANET due to its highly dynamic nature. We propose a simple model for computing link stability and route stability based on received signal strengths. By including some extra fields in route request/reply packets, the route stability information can be utilized to select a route with higher stability among all the feasible routes between a given source destination pair. Further, inclusion of a signal strength based admission control enhances the performance of the routing. Results of our experiments show performance improvements in terms of packet delivery ratio, control overhead and average end-to-end delay in comparison with a QoS routing protocol proposed by Q. Xue and A. Ganz.     

无线adhoc网络中的多径源路由

本文针对无线ad hoc网络提出了一种基于DSR(动态源路由)的路由算法,多径源路由(MSR).MSR对DSR中的路由搜索和路由维护机制进行了扩展,用来解决多径路由问题.本文还提出,在多条路径之间基于测量的RTT进行负载分配.仿真结果表明,MSR在只增加少量网络开销的情况下,提高了TCP和UDP的投递率,降低了丢包率,并减少了端到端之间的延迟以及队列长度,从而有效地减少了网络拥塞.     

Multiconstrained and multipath QoS aware routing protocol for MANETs

The multimedia applications such as audio, video transmission in Mobile Ad Hoc Network (MANET) requires that the path in which such data transmits must be delay sensitive, reliable and energy efficient. An existing MANET routing protocol Ad Hoc On demand Multipath Distance Vector (AOMDV) fails to perform well in terms of QoS metrics such as delay, jitter, packet delivery ratio (PDR) etc., where there is high mobility and heavy traffic. The paths which are stored in the Routing table are not reliable and energy efficient. It is possible to modify the route discovery of AODV so that more than one node disjoint, link reliable and energy efficient paths are stored in the routing table. The proposed protocol Multiconstrained and Multipath QoS Aware Routing Protocol (MMQARP) is novel, which takes care of QoS parameters dynamically and simultaneously along with path finding, so that only link reliable, energy efficient paths are available for data transmission. The extensive simulation study shows that the proposed protocol performs better in terms of PDR, delay and jitter compared to AOMDV protocol.     

Exploiting path diversity in the link layer in wireless ad hoc networks

We develop an anycast mechanism at the link layer for wireless ad hoc networks. The goal is to exploit path diversity in the link layer by choosing the best next hop to forward packets when multiple next hop choices are available. Such choices can come from a multipath routing protocol, for example. This technique can reduce transmission retries and packet drop probabilities in the face of channel fading. We develop an anycast extension of the IEEE 802.11 MAC layer based on this idea. We implement the protocol in an experimental proof-of-concept testbed using the Berkeley motes platform and S-MAC protocol stack. We also implement it in the popular ns-2 simulator and experiment with the AOMDV multipath routing protocol and Ricean fading channels. We show that anycast performs significantly better than 802.11 in terms of packet delivery, particularly when the path length or effect of fading is large. Further we experiment with anycast in networks that use multiple channels and those that use directional antennas for transmission. In these networks, deafness and hidden terminal problems are the main source of packet loss. We implemented anycast as extension of 802.11 like protocols that were proposed for these special networks. We are able to show that anycast is capable of enhancing the performance of these protocols by simply making use of the path diversity whenever it is available.     

Formal verification of a new authenticated and optimized version of AOMDV for WSN

In this paper, we propose a formal study based on model checking to formally verify an enhancement authenticated version of ad hoc on‐demand multipath distance vector (AOMDV) called authenticated optimized AOMDV (AO‐AOMDV). In this new version, we have added new functionalities in route discovery and route maintenance processes combined with the advantages of μTESLA. This contribution allows a transmitter to compute multiple authenticated routing paths toward the destination. The result of the formal verification study, under UPPAAL and SPIN, shows the behavior of the protocol that may not be revealed by simulation.