Efficient on-demand routing for mobile ad hoc wireless access networks

In this paper, we consider a mobile ad hoc wireless access network in which mobile nodes can access the Internet via one or more stationary gateway nodes. Mobile nodes outside the transmission range of the gateway can continue to communicate with the gateway via their neighboring nodes over multihop paths. On-demand routing schemes are appealing because of their low routing overhead in bandwidth restricted mobile ad hoc networks, however, their routing control overhead increases exponentially with node density in a given geographic area. To control the overhead of on-demand routing without sacrificing performance, we present a novel extension of the ad hoc on-demand distance vector (AODV) routing protocol, called LB-AODV, which incorporates the concept of load-balancing (LB). Simulation results show that as traffic increases, our proposed LB-AODV routing protocol has a significantly higher packet delivery fraction, a lower end-to-end delay and a reduced routing overhead when compared with both AODV and gossip-based routing protocols.     

SMORT: Scalable multipath on-demand routing for mobile ad hoc networks

Increasing popularity and availability of portable wireless devices, which constitute mobile ad hoc networks, calls for scalable ad hoc routing protocols. On-demand routing protocols adapt well with dynamic topologies of ad hoc networks, because of their lower control overhead and quick response to route breaks. But, as the size of the network increases, these protocols cease to perform due to large routing overhead generated while repairing route breaks. We propose a multipath on-demand routing protocol (SMORT), which reduces the routing overhead incurred in recovering from route breaks, by using secondary paths. SMORT computes fail-safe multiple paths, which provide all the intermediate nodes on the primary path with multiple routes (if exists) to destination. Exhaustive simulations using GloMoSim with large networks (2000 nodes) confirm that SMORT is scalable, and performs better even at higher mobility and traffic loads, when compared to the disjoint multipath routing protocol (DMRP) and ad hoc on-demand distance vector (AODV) routing protocol.     

A highly topology adaptable ad hoc routing protocol with complementary preemptive link breaking avoidance and path shortening mechanisms

Ad-hoc on-demand distance vector routing (AODV) is a well-known routing protocol for mobile ad hoc networks. The original AODV protocol works in a semi-dynamic fashion, by establishing a route on demand and using that route until it breaks. However, to suit the changing network topology of ad hoc networks, more aggressive and adaptable routing strategies are required. A number of researches have proposed improving AODV performance by locally repairing broken links, predicting and replacing potentially vulnerable links, or shortening a link through removing redundant nodes from the transmission path. Although local repair may relieve some problems, it usually results in longer paths and thus a considerable performance drop in heavy traffic conditions. There are also issues regarding packet loss and communication delay due to route rebuilding once the link is broken. Predicting and replacing potentially vulnerable links may require special hardware, additional tables to maintain, or other extra overhead. Finally, path shortening may result in shorter and more efficient routes, but there is no guarantee that the new paths will be robust. This paper proposes integrating preemptive link breaking avoidance and path shortening mechanisms into a modified AODV protocol. However, the difficult issue lies in determining the right timing to initiate the two independent mechanisms so that the two dynamically and complementarily operating mechanisms can work together to improve the routing performance. Through numerical analysis and simulation, we have arranged a simple parameter setting for controlling the activation of each mechanism at the appropriate time. The proposed combination is a highly dynamic ad hoc routing protocol that is capable of adapting itself to the changing network topology and achieving extremely good performance in various routing performance metrics. Extensive simulations show that each of the two schemes alone improves AODV performance. More importantly, the integrated protocol performs even better in terms of data delivery rate, average delay time, and network overhead. To be more specific, in the best cases our protocol can reduce up to 82% in control overhead and 66% in delay time, while achieving 12% more in data delivery rate comparing to AODV.     

路由信息的攻击对AODV协议性能的影响分析

AODV协议是移动自组网络中一种按需反应的表驱动路由协议。在移动自组网中，每个节点既是计算机又是路由器，容易遭受基于路由信息的网络攻击，而现今的路由协议基本没有考虑到该问题。本文在分析移动自组网中针对路由信息主要攻击方法的基础上，建立了主动性和自私性两个攻击模型，并且在AODV协议中扩充实现了这两类攻击行为。通过对模拟结果的分析和比较，讨论了路由信息的攻击对AODV协议性能的影响，并进一步探讨了针对基于路由信息攻击的防御措施。     

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.     

Study of MANET routing protocols by GloMoSim simulator

This paper compares ad hoc on‐demand distance vector (AODV), dynamic source routing (DSR) and wireless routing protocol (WRP) for MANETs to distance vector protocol to better understand the major characteristics of the three routing protocols, using a parallel discrete event‐driven simulator, GloMoSim. MANET (mobile ad hoc network) is a multi‐hop wireless network without a fixed infrastructure. Following are some of our key findings: (1) AODV is most sensitive to changes in traffic load in the messaging overhead for routing. The number of control packets generated by AODV became 36 times larger when the traffic load was increased. For distance vector, WRP and DSR, their increase was approximately 1.3 times, 1.1 times and 7.6 times, respectively. (2) Two advantages common in the three MANET routing protocols compared to classical distance vector protocol were identified to be scalability for node mobility in end‐to‐end delay and scalability for node density in messaging overhead. (3) WRP resulted in the shortest delay and highest packet delivery rate, implying that WRP will be the best for real‐time applications in the four protocols compared. WRP demonstrated the best traffic scalability; control overhead will not increase much when traffic load increases. Copyright © 2005 John Wiley & Sons, Ltd.     

Scalability enhancement of AODV using local link repairing

Dynamic change in the topology of an ad hoc network makes it difficult to design an efficient routing protocol. Scalability of an ad hoc network is also one of the important criteria of research in this field. Most of the research works in ad hoc network focus on routing and medium access protocols and produce simulation results for limited-size networks. Ad hoc on-demand distance vector (AODV) is one of the best reactive routing protocols. In this article, modified routing protocols based on local link repairing of AODV are proposed. Method of finding alternate routes for next-to-next node is proposed in case of link failure. These protocols are beacon-less, means periodic hello message is removed from the basic AODV to improve scalability. Few control packet formats have been changed to accommodate suggested modification. Proposed protocols are simulated to investigate scalability performance and compared with basic AODV protocol. This also proves that local link repairing of proposed protocol improves scalability of the network. From simulation results, it is clear that scalability performance of routing protocol is improved because of link repairing method. We have tested protocols for different terrain area with approximate constant node densities and different traffic load.     

Status adaptive routing with delayed rebroadcast scheme in AODV-based MANETs

An efficient solution is proposed in this article to determine the best reliable route and to prolong the lifetime of the mobile Ad-hoc networks （MANETs）. In the proposed solution, the route discovery process of the Ad-hoc on-demand distance vector routing protocol （AODV） has been modified using a novel delayed rebroadcast scheme. It combines the shortest route selection criterion of AODV with the real network status including the wireless link quality, the remaining power capacity, as well as the traffic load at each node. Simulation results show that the proposed scheme can significantly extend the network lifetime and provide fewer packet losses than the conventional AODV protocol.     

Maximum battery life routing to support ubiquitous mobile computingin wireless ad hoc networks

Most ad hoc mobile devices today operate on batteries. Hence, power consumption becomes an important issue. To maximize the lifetime of ad hoc mobile networks, the power consumption rate of each node must be evenly distributed, and the overall transmission power for each connection request must be minimized. These two objectives cannot be satisfied simultaneously by employing routing algorithms proposed in previous work. We present a new power-aware routing protocol to satisfy these two constraints simultaneously; we also compare the performance of different types of power-related routing algorithms via simulation. Simulation results confirm the need to strike a balance in attaining service availability performance of the whole network vs. the lifetime of ad hoc mobile devices     

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。     

Minimisation de la consommation d’Énergie dans les réseaux ad hoc

An ad hoc network is a collection of wireless devices forming a temporary network independently of any administration or fixed infrastructure. The main benefits of this new generation of mobile networks are flexibility and their low cost. Wireless devices have maximum utility when they can be used “anywhere at anytime “. However, one of the greatest limitations to that goal is the finite power supplies. Since batteries provide limited power, a general constraint of wireless communication is the short continuous operation time of mobile terminals. This constraint is more important for the ad hoc networks, since every terminal has to perform the functions of a router. Therefore, energy consumption should be a crucial issue while designing new communication protocols and particularly ad hoc routing protocols. We propose, in this paper, some extensions to the most important on-demand routing algorithm,Aodv (Ad hoc On demand Distance Vector). The discovery mechanism in these extensions uses energy as a routing metric. These algorithms improve the network survivability by maintaining the network connectivity, which is the strong requirement for a high-quality communication. They carry out this objective with low message overhead for computing routes and without affecting the other network protocol layers.     

基于NS2的无线自组织网络路由协议仿真

在无线自组织网络中,由于节点移动,网络拓扑结构变化频繁,所以路由协议的选择一直都是关键问题。该文采用NS2软件对两种主要的协议：动态源路由协议（DSR）和自组网按需距离矢量路由协议（AODV）进行了仿真。并且通过端到端延时、路由开销和分组投递率三种参数在不同条件下的数据对两种协议进行了评估。实验结果表明没有一种协议能够完全适用于自组网,对于特殊环境选择不同协议以满足需要。     

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.     

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.     

Performance Evaluation of Improved Directional Ad Hoc on Demand Distance Vector Routing Protocol

Mobile ad hoc networks (MANET’s) popularly uses ad hoc on-demand distance vector (AODV) routing protocol. Past research has identified certain limitations on performance on AODV. This work discusses the results of a new protocol, improved directional AODV (ID-AODV) routing protocol; that has succeeded in improving the performance of MANET’s for energy, delay, packet delivery ratio and overheads as compared with networks using AODV. In ID-AODV, improvements are carried out in both network layer, and data link layer. The directionality is introduced based on hop count of its position from the source. The dual sensing directional media access control protocol is used to eliminate the hidden terminal, exposed terminal, and deafness issue. Participation of nodes in forming route is decided by checking remaining energy level of the node and also checking its load. A modified algorithm is used to reduce the delay. This algorithm reduces the delay by changing the time to live, wait time, and using expanded ring search technique. The simulation results show that the ID-AODV offers improved performance on average Energy consumption in the range of 17–20%, average end to end delay is lower by 61 to 95%, Overheads improved in the range of 10–13%, Jitter 6–21%, link break 43–52%, packet delivery ratio is 6–21% lower as compared to MANETS deploying AODV.     

Routing Algorithms for MANET-IoT Networks: A Comprehensive Survey

With the powerful evolution of wireless communication systems in recent years, mobile ad hoc networks (MANET) are more and more applied in many fields such as environment, energy efficiency, intelligent transport systems, smart agriculture, and IoT ecosystems, as well as expected to contribute role more and more important in the future Internet. However, due to the characteristic of the mobile ad hoc environment, the performance is dependent mainly on the deployed routing protocol and relative low. Therefore, routing protocols should be more flexible and intelligent to enhance network performance. This paper surveyed and analysed a series of recently proposed routing protocols for MANET-IoT networks. Results have shown that these protocols are classified into four main categories: performance improvement, quality of service (QoS-aware), energy-saving, and security-aware. Most protocols are evolved from these existing traditional protocols. Then, we compare the performance of the four traditional routing protocols under the different movement speeds of the network node aim determines the most stable routing protocol in smart cities environments. The experimental results showed that the proactive protocol work is good when the movement network nodes are low. However, the reactive protocols have more stable and high performance for high movement network scenarios. Thus, we confirm that the proposal of the routing protocols for MANET becomes more suitable based on improving the ad hoc on-demand distance vector routing protocol. This study is the premise for our further in-depth research on IoT ecosystems.

     

Reliable Distributed Local Repair Approach for Maximizing Reliability and Packet Delivery Rate in Wireless on Demand AODV Networks

The most used protocol in Mobile Ad hoc Networks (MANETs) uses the Ad hoc On-Demand Distance Vector (AODV) routing protocol for achieving dynamic, self-organizing, and on-demand multihop routing. In AODV, wireless links may be lost occasionally because the nodes on the routing path are unreachable. Such a problem causes AODV inefficient and unreliable. For solving the problem, AODV provides a local repair mechanism for an intermediate node to find an alternative route to destination when the node detects links broken. The repair mechanism uses the broadcast-type RREQ message for discovering a repair route, which results in a large number of repair control messages and requires a large amount of power consumption for sending these messages. Therefore, in this paper we propose a unicast-type distributed local repair protocol for repairing breaks expeditiously, i.e., achieving high network reliability and utilization, less the number of control messages, and less the repair delay. Furthermore, the optimal number of hops in a neighbor table is analyzed. Numerical results indicate that the proposed approach is superior to other repair approaches in terms of successful fixing rate, control message overhead, and network utilization.     

A simulation study of table-driven and on-demand routing protocolsfor mobile ad hoc networks

Bandwidth and power constraints are the main concerns in current wireless networks because multihop ad hoc mobile wireless networks rely on each node in the network to act as a router and packet forwarder. This dependency places bandwidth, power, and computation demands on mobile hosts which must be taken into account when choosing the best routing protocol. In previous years, protocols that build routes based on demand have been proposed. The major goal of on-demand routing protocols is to minimize control traffic overhead. We perform a simulation and performance study on some routing protocols for ad hoc networks. The distributed Bellman-Ford (1957, 1962), a traditional table-driven routing algorithm, is simulated to evaluate its performance in multihop wireless network. In addition, two on-demand routing protocols (dynamic source routing and associativity-based routing) with distinctive route selection algorithms are simulated in a common environment to quantitatively measure and contrast their performance. The final selection of an appropriate protocol will depend on a variety of factors, which are discussed in this article     

一种增加时限和延迟的AODV协议改进方法

AODV协议是目前比较成熟的应用于移动自组网(MANET)中的一种反应式路由协议,其缺点主要是协议开销比较大,运动情况下路由优化性能不理想。利用为RREQ消息设置时限和为中间节点根据自身队长设置回复RREP消息延迟的方法,提出了一种改进的AODV协议(AODV-DL),有效地提高了网络的投包率和路由优化性能,降低了网络的协议开销。提出了将路由优化性能作为协议的一项新的评价标准。描述了其实现策略,并给出了NS2下的仿真结果。     

Distributed Power Control for Energy Efficient Routing in Ad Hoc Networks

In this paper, distributed power control is proposed as a means to improve the energy efficiency of routing algorithms in ad hoc networks. Each node in the network estimates the power necessary to reach its own neighbors, and this power estimate is used both for tuning the transmit power (thereby reducing interference and energy consumption) and as the link cost for minimum energy routing. With reference to classic routing algorithms, such as Dijkstra and Link State, as well as more recently proposed ad hoc routing schemes, such as AODV, we demonstrate by extensive simulations that in many cases of interest our scheme provides substantial transmit energy savings while introducing limited degradation in terms of throughput and delay.