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。     

Performance Analysis of P-GEDIR Protocol for Vehicular Ad Hoc Network in Urban Traffic Environments

A Vehicular Ad hoc Network (VANET) is a wireless ad hoc network that is formed between vehicles on an on demand basis. In VANETs all the vehicles (nodes) are used as routers and these routers are free to move randomly and organized themselves arbitrarily. A lot of research work around the world is being conducted to design an efficient routing protocol for VANETs. In this paper, we propose a new routing method known as Peripheral node based GEographic DIstance Routing (P-GEDIR), a position-based routing protocol that takes advantage of GEographic DIstance Routing (GEDIR). It may not be possible to find node at the extreme end of the transmission range. Therefore, we have considered an area around the extreme end of the transmission range. Further a mathematical model for the protocol has been designed to determine expected number of successful hops, expected distance to the next-hop node, and expected one-hop progress. The protocol has been simulated using MATLAB. In this work, results clearly show that using the peripheral node is an advantage to maximize the performance of routing protocol in terms of average number of successful hops and expected one-hop progress. The result of P-GEDIR is compared with the existing GEDIR protocol.     

Routing security in wireless ad hoc networks

A mobile ad hoc network consists of a collection of wireless mobile nodes that are capable of communicating with each other without the use of a network infrastructure or any centralized administration. MANET is an emerging research area with practical applications. However, wireless MANET is particularly vulnerable due to its fundamental characteristics, such as open medium, dynamic topology, distributed cooperation, and constrained capability. Routing plays an important role in the security of the entire network. In general, routing security in wireless MANETs appears to be a problem that is not trivial to solve. In this article we study the routing security issues of MANETs, and analyze in detail one type of attack-the "black hole" problem-that can easily be employed against the MANETs. We also propose a solution for the black hole problem for ad hoc on-demand distance vector routing protocol.     

SEAD: secure efficient distance vector routing for mobile wireless ad hoc networks

An ad hoc network is a collection of wireless computers (nodes), communicating among themselves over possibly multihop paths, without the help of any infrastructure such as base stations or access points. Although many previous ad hoc network routing protocols have been based in part on distance vector approaches, they have generally assumed a trusted environment. In this paper, we design and evaluate the Secure Efficient Ad hoc Distance vector routing protocol (SEAD), a secure ad hoc network routing protocol based on the design of the Destination-Sequenced Distance-Vector routing protocol. In order to support use with nodes of limited CPU processing capability, and to guard against Denial-of-Service attacks in which an attacker attempts to cause other nodes to consume excess network bandwidth or processing time, we use efficient one-way hash functions and do not use asymmetric cryptographic operations in the protocol. SEAD performs well over the range of scenarios we tested, and is robust against multiple uncoordinated attackers creating incorrect routing state in any other node, even in spite of any active attackers or compromised nodes in the network.     

Authenticated routing for ad hoc networks

Initial work in ad hoc routing has considered only the problem of providing efficient mechanisms for finding paths in very dynamic networks, without considering security. Because of this, there are a number of attacks that can be used to manipulate the routing in an ad hoc network. In this paper, we describe these threats, specifically showing their effects on ad hoc on-demand distance vector and dynamic source routing. Our protocol, named authenticated routing for ad hoc networks (ARAN), uses public-key cryptographic mechanisms to defeat all identified attacks. We detail how ARAN can secure routing in environments where nodes are authorized to participate but untrusted to cooperate, as well as environments where participants do not need to be authorized to participate. Through both simulation and experimentation with our publicly available implementation, we characterize and evaluate ARAN and show that it is able to effectively and efficiently discover secure routes within an ad hoc network.     

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.     

The Effects of Physical Layer on the Routing Wireless Protocol

Mobile ad hoc networks (MANETs) are characterized by multiple entities, a frequently changing network topology and the need for efficient dynamic routing protocols. In MANETs, nodes are usually powered by batteries. Power control is tightly coupled with both the physical and medium access layers (MACs). However, if we increase the transmission power, at the same time we increase the interference to other nodes which diminish the transport capacity of wireless systems. Thus, the routing protocols based on hop count metric suffer from performance degradation when they operate over MANET. Routing in ad hoc wireless networks is not only a problem of finding a route with shortest length, but it is also a problem of finding a stable and good quality communication route in order to avoid any unnecessary packet loss. Cross-layer design of ad hoc wireless networks has been receiving increasing attention recently. Part of these researches suggests that routing should take into account physical layer characteristics. The goal of this paper is to improve the routing reliability in MANET and to reduce power consumption through cross-layer approach among physical, MAC and network layers. The proposed cross-layer approach is based on signal to interference plus noise ratio (SINR) and received signal strength indication (RSSI) coming from the physical layer. This solution performs in one hand the ad hoc on-demand distance vector routing protocol by choosing reliable routes with less interferences using SINR metric and in another hand; it permits to reduce the power transmission when sending the data packets by using RSSI metric.     

ABRP: Anchor-based Routing Protocol for Mobile Ad Hoc Networks

Ad hoc networks, which do not rely on any infrastructure such as access points or base stations, can be deployed rapidly and inexpensively even in situations with geographical or time constraints. Ad hoc networks are attractive in both military and disaster situations and also in commercial uses like sensor networks or conferencing. In ad hoc networks, each node acts both as a router and as a host. The topology of an ad hoc network may change dynamically, which makes it difficult to design an efficient routing protocol. As more and more wireless devices connect to the network, it is important to design a scalable routing protocol for ad hoc networks. In this paper, we present Anchor-based Routing Protocol (ABRP), a scalable routing protocol for ad hoc networks. It is a hybrid routing protocol, which combines the table-based routing strategy with the geographic routing strategy. However, GPS (Global Positioning System) (Kaplan, Understanding GPS principles and Applications, Boston: Artech House publishers, 1996) support is not needed. ABRP consists of a location-based clustering protocol, an intra-cell routing protocol and an inter-cell routing protocol. The location-based clustering protocol divides the network region into different cells. The intra-cell routing protocol routes packets within one cell. The inter-cell routing protocol is used to route packets between nodes in different cells. The combination of intra-cell and inter-cell routing protocol makes ABRP highly scalable, since each node needs to only maintain routes within a cell. The inter-cell routing protocol establishes multiple routes between different cells, which makes ABRP reliable and efficient. We evaluate the performance of ABRP using ns2 simulator. We simulated different size of networks from 200 nodes to 1600 nodes. Simulation results show that ABRP is efficient and scales well to large networks. ABRP combines the advantages of multi-path routing strategy and geographic routing strategy—efficiency and scalability, and avoids the burden—GPS support.     

AODV_RR: A Maximum Transmission Range Based Ad Hoc on-Demand Distance Vector Routing in MANET

Nodes in a mobile ad hoc network are battery constrained devices and energy efficiency becomes an important consideration. In a multi-hop mobile ad hoc network the most common method to achieve energy efficiency is the transmission power control scheme in which a node transmits the data packets to its nearest neighbor which is at minimum required power level. However this scheme minimizes only the transmission power within the node’s neighborhood and energy efficiency at the link level is possible. With this scheme it is not possible to minimize the overall energy consumption of the network and the communication overhead of the network is not minimized. An analysis has been performed and our results have proved that instead of using low transmission power, the routing strategy needs to be controlled and only certain nodes are to be allowed to receive and process this routing request based on the received signal strength, then the overall energy consumption of the network can be minimized and the communication overhead is also minimized. The modified routing strategy is applied to the basic ad hoc on-demand distance vector (AODV) routing protocol and a maximum transmission range based ad hoc on-demand distance vector routing protocol named AODV range routing (AODV_RR) is proposed and studied under different network sizes. Measurable difference in performance is realized and the proposed AODV_RR perform better than normal AODV with respect to all the selected metrics.     

A Dynamic Alternate Path QoS Enabled Routing Scheme in Mobile Ad hoc Networks

A mobile ad hoc network (MANET) is a collection of self-organized mobile nodes that are capable of communicating with each other without the aid of any established infrastructure or centralized administration. Routing algorithm has been a challenge task in the wireless ad hoc network for a long time due to the dynamic nature of network topology. A recent trend in ad hoc network routing is the reactive on-demand philosophy where routes are established only when required. The on-demand routing protocol for ad hoc network is appealing because of its low routing overhead and its effectiveness when the frequency of route re-establishment and the demand of route queries are not high. However, considering the increasing demand of Quality-of-Service (QoS) requirements in many applications, the current on-demand routing protocols used for ad-hoc network should be adapted appropriately to effectively meet the stringent QoS requirements of specific multimedia traffic. We thus propose a routing protocol which tries its best to satisfy QoS requirements of specific multimedia traffic in the volatile environments of a MANET. The results of a series of simulations exhibit the practicability and feasibility of our approaches. This research was partially supported by National Science Council under grant NSC 93-2213-E-026-001     

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.     

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.

     

用于Ad Hoc网络的多径混合路由

移动Ad hoc网络是由一组移动节点组成的临时网络,它不需要事先建立的网络基础设施的支持。路由协议对网络性能起着决定性的作用。文中提出了一种基于多路径的Ad hoc网络混合路由策略（MPHR）。在MPHR中,边权值表示节点之间的链路可靠性。与传统的单路径路由策略不同,在一对源节点和目的节点间,使用多条路径来发送分组。仿真结果表明,MPHR的分组投递率远高于DSR路由协议,但路由开销略大于DSR。     

Statistical Multipath Queue-Wise Preemption Routing for ZigBee-Based WSN

Nowadays, wireless sensor network (WSN) is an important component in IoT environment, which enables efficient data collection and transmission. Since WSN consists of a large number of sensor nodes, network congestion can easily occur which significantly degrades the performance of entire network. In this paper a novel scheme called SMQP (Statistical Multipath Queue-wise Preemption) routing is proposed to balance the load and avoid the congestion for ZigBee-based WSN. This is achieved by employing statistical path scheduling and queue-wise preemption with multiple paths between any source and destination node. NS2 simulation reveals that the proposed scheme significantly improves the QoS in terms of delivery ratio, end-to-end delay, and packet delivery ratio compared to the representative routing schemes for WSN such as ad hoc on-demand distance vector and ad hoc on-demand multipath distance vector scheme.     

OLSR performance measurement in a military mobile ad hoc network

Wireless ad hoc networks are autonomous, self-configurating and adaptive. Thus, such networks are excellent candidates for military tactical networks, where their ability to be operational rapidly and without any centralized entity is essential. As radio coverage is usually limited, multihop routing is often needed; this is achieved by an ad hoc routing protocol supporting nodes mobility. In this paper, we present performance measurements of the Optimized Link State Routing (OLSR) routing protocol, having the status of IETF RFC. The measurements are performed at CELAR site on a platform representative of military scenarios in urban areas. This platform consists of ten routers, eight PDAs and laptops using a IEEE 802.11b radio interface and implementing OLSR v7. Some nodes are mobile within vehicles. The emphasis of the measurements is on the performance of the network (route repair, network convergence speed, user traffic performance) in presence of this mobility.     

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。     

Simulation of Ad Hoc Routing Protocols using OMNeT++

Mobile Ad Hoc Networks (MANETs) have evolved in the last years into standards in the communication world. By definition, they do not need any network infrastructure to facilitate communication between participating nodes. Therefore, MANETs are dealing with new challenges in the context of ad hoc routing. Simulation techniques are one of the fundamental methodologies to support the protocol engineering process, especially in the early stages of ad hoc network protocol design. In this paper, we set out common criteria that may serve as guidelines for meaningful simulative evaluations of ad hoc routing protocols. We present typical and necessary measures for ad hoc routing in general and MANET routing in particular. As a case study, we demonstrate a comprehensive performance evaluation of the Dynamic MANET On Demand (DYMO) routing protocol using a model we implemented for the popular OMNeT+ + discrete event simulation environment.     

Carrier sense aware multipath geographic routing protocol

Over the last few years, wireless sensor networks have become a great field of interest for the scientific community. This novel kind of network provides an array of applications for different aspects of human life. To give a satisfying performance to the final user, the wireless sensor networks must ensure the quality of service. The use of multipath technique was widely applied in the literature. Nevertheless, there might be a problem if the interference issues are not taken into account by the multipath routing design. In this paper, we propose a novel multipath routing protocol called Carrier Sense Aware Multipath Geographic Routing protocol (CSA‐MGR). This protocol creates multiple paths while avoiding any shared carrier sense range by using a distributed and dynamic process. In addition, the CSA‐MGR employs a new metrics named the Number of Common Neighbors to guarantee a faster and an efficient path construction. Simulations conducted over the NS‐2 simulator show promising results in terms of delay, Packet Delivery Ratio and routing overhead. The performance gain of CSA‐MGR in terms of delay is up to 275% compared with the Two‐Phase geographical Greedy Forwarding and up to 565% compared with the ad hoc on‐demand multipath distance vector. For the Packet Delivery Ratio, the performance gain of CSA‐MGR is up to 16% compared with the Two‐Phase geographic Greedy Forwarding and up to 28% compared with the ad hoc on‐demand multipath distance vector. Copyright © 2015 John Wiley & Sons, Ltd.     

Multi-Level Hierarchies for Scalable Ad hoc Routing

Ad hoc networks have the notable capability of enabling spontaneous networks. These networks are self-initializing, self-configuring, and self-maintaining, even though the underlying topology is often continually changing. Because research has only begun to scratch the surface of the potential applications of this technology, it is important to prepare for the widespread use of these networks. In anticipation of their ubiquity, the protocols designed for these networks must be scalable. This includes scaling to both networks with many nodes, and networks with rapidly changing topologies. This paper presents two hierarchical clustering protocols that improve the scalability of ad hoc routing protocols. The Adaptive Routing using Clusters (ARC) protocol creates a one-level clustered hierarchy across an ad hoc network, while the Adaptive Routing using Clustered Hierarchies (ARCH) protocol creates a multi-level hierarchy which is able to dynamically adjust the depth of the hierarchy in response to the changing network topology. It is experimentally shown that these protocols, when coupled with an ad hoc routing protocol, produce throughput improvements of up to 80% over the ad hoc routing protocol alone.