Triangle-based routing for mobile ad hoc networks

Routing protocols for Mobile ad hoc networks (MANETs) have been studied extensively in the past decade. Routing protocols for MANETs can be broadly classified as reactive (on-demand), proactive, hybrid and position-based. Reactive routing protocols are attractive because a route between a source and a destination is established only when it is needed. Such protocols, unlike proactive protocols, do not have high overhead for route maintenance and are especially suitable for networks in which not all nodes communicate frequently. One problem with existing reactive routing protocols is the propagation of redundant route request messages during route discovery. In this paper, we present a low-overhead reactive routing protocol which reduces propagation of redundant route request messages. We also compare its performance with the well-known reactive routing protocol AODV.     

Dynamic backup routes routing protocol for mobile ad hoc networks

Mobile Ad Hoc Networks (MANETs), which provide data networking without infrastructure, represent one kind of wireless networks. A MANET is a self-organizating and adaptive wireless network formed by the dynamic gathering of mobile nodes. Due to the mobility of mobile nodes, the topology of a MANET frequently changes and thus results in the disability of originally on-the-fly data transmission routes. The dynamic properties of MANETs are therefore challenging to protocol design. To cope with the intrinsic properties of MANETs, Dynamic Backup Routes Routing Protocol (DBR²P), a backup node mechanism for quick reconnection during link failures, is proposed in this paper. DBR²P is an on-demand routing protocol and it can set up many routes to reach a destination node in a given period. Even when a link fails, those routes from the source node to the destination node can be analyzed to obtain backup routes to sustain quick reconnection. The information of backup routes can be saved in a specific on-the-route node and enables backup routes to be found immediately in situation regarding disconnection. As a result, DBR²P could more thoroughly improve the quality of routing protocol than those proposed in the past.     

Service discovery in mobile ad hoc networks: A field theoretic approach

Service discovery in mobile ad hoc networks is challenging because of the absence of any central intelligence in the network. Traditional solutions as used in the Internet are hence not well suited for mobile ad hoc networks. In this paper, we present a novel decentralized service discovery mechanism for ad hoc networks. The basic idea is to distribute information about available services to the network neighborhood. We achieve this by using the analogy of an electrostatic field: A service is modelled by a (positive) point charge, and service request packets are seen as (negative) test charges which are attracted by the service instances. In our approach, we map the physical model to a mobile ad hoc network in a way where each network element calculates a potential value and routes service requests towards the neighbor with the highest potential, hence towards a service instance. Our approach allows for differentiation of service instances based on their capacity. We define the required protocols and methods which we implemented in a network simulator. Using extensive simulations, we evaluate the performance and robustness of the mechanisms. The results indicate good performance and convergence even in highly mobile environments. We believe that this technique can and should be further exploited, e.g., as a routing protocol in mobile ad hoc networks.     

间断移动自组织网络下的路由协议分析与增强

文章介绍并分析了基本的间断移动自组织网络的路由协议的原理和性能。通过引入概率的思想和称之为捎带删除的垃圾收集方式,提出了一种路由增强算法EEPI。仿真结果表明,该协议明显减小了系统消耗,提高了路由效率,具有较强的适应不同场景的特性。     

Using an evolutionary algorithm to optimize the broadcasting methods in mobile ad hoc networks

A mobile ad hoc network (MANET) is a collection of mobile nodes communicating through wireless connections without any prior network infrastructure. In such a network the broadcasting methods are widely used for sending safety messages and routing information. To transmit a broadcast message effectively in a wide and high mobility MANET (for instance in vehicular ad hoc network) is a hard task to achieve. An efficient communication algorithm must take into account several aspects like the neighborhood density, the size and shape of the network, the use of the channel. Probabilistic strategies are often used because they do not involve additional latency. Some solutions have been proposed to make their parameters vary dynamically. For instance, the retransmission probability increases when the number of neighbors decreases. But, the authors do not optimize parameters for various environments. This article aims at determining the best communication strategies for each node according to its neighborhood density. It describes a tool combining a network simulator (ns-2) and an evolutionary algorithm (EA). Five types of context are considered. For each of them, we tackle the best behavior for each node to determine the right input parameters. The proposed EA is first compared to three EAs found in the literature: two well-known EAs (NSGA-II and SPEA2) and a more recent one (DECMOSA-SQP). Then, it is applied to the MANET broadcasting problem.     

An evolutionary computation approach for designing mobile ad hoc networks

This paper presents the topological design of ad hoc networks in terms of distances among static nodes and speeds of mobiles nodes. Due to the complexity of the problem and the number of parameters to be considered, a genetic algorithm combined with the simulation environment NS-2 is proposed to find the optimum solution. More specifically, NS-2 provides the fitness function guiding the genetic search. The proposed framework has been tested using a railway scenario in which several static and mobile nodes are interacting. Results show the feasibility of the proposed framework and illustrate the possibility of genetic approach for solving similar application scenarios.     

AODV‐RIP: improved security in mobile ad hoc networks through route investigation procedure

Most routing protocols in mobile ad hoc networks (MANETs) place an emphasis on finding paths in dynamic networks without considering security. As a result, there are a number of attacks that can be used to manipulate the routing in MANET. A malicious node that sends a modified control message to an intermediate node can disturb the network using a control message. To solve this problem, we introduce AODV protocol with route investigation procedure (AODV‐RIP). It uses two additional control messages to defeat security attacks that can occur in AODV routing protocol. When an intermediate node that is on the path between the source node and the destination node receives a control message, it sends a Rroute Investigation Request (IREQ) message to the destination node in order to check the reliability of the control message. According to the existence of Route Investigation Reply (IREP), the intermediate node decides whether it transmits the control message to the source node or not. Consequently, the intermediate node that receives the control message confirms that it is using two additive control messages: IREQ and IREP. Through this investigation procedure, the source node can obtain a reliable path for transmitting data packets to an intentional destination node. The simulation results show an improvement in the packet delivery ratio and end‐to‐end delay at the expense of a moderate increase of the control message overhead compared with the current routing protocols. Copyright © 2009 John Wiley & Sons, Ltd.     

基于模糊控制的ad hoc网络TCP算法研究

TCP协议是针对固定可靠网络设计的一种传输协议,它把数据包丢失或延迟的原因都归结为网络拥塞。在移动自组网上直接应用TCP 协议,网络性能会因比特出错率高等原因大幅下降。针对无线自组织网络高误码的基本特征,基于TCP Vegas协议和环回时间的均值和方差改变趋势,采用不同的控制策略调节发送端的数据发送速率,从而优化传输控制协议的吞吐量,提高网络资源的利用率。仿真研究结果表明,与传统的传输控制协议相比,该算法具有更高的吞吐量和稳定的拥塞控制窗口。     

Review of multicast routing mechanisms in mobile ad hoc networks

Frequent interactions among the group members of distributed wireless network environment may be facilitated with the help of Mobile Ad Hoc NETworks (MANETs). Some of the group-oriented applications include disaster management, battlefields, audio/video conferencing, e-commerce, e-education, etc. Group communication demands dynamic construction of efficient and reliable multicast routes under user mobility and varying channel conditions. Multicast routing mechanisms in MANETs have been consistently improved by researchers considering various performance measures such as energy efficient route establishment, packet delivery ratio, quicker and faster proactive route recovery, network life time, reliability, Quality of Service (QoS) based on bandwidth, delays, jitters, and security. The paper focuses on most recent reliable and QoS based multicast routing mechanisms that helps in multimedia communication over MANETs. The mechanisms are considered under different topological routing categories such as mesh, tree, zone and hybrid. We provide an overview of existing multicast routing mechanisms based on routing categories and point to directions for future research and development.     

Dynamic route maintenance for geographic forwarding in mobile ad hoc networks

Traditional route maintenance requires mobile nodes periodically exchange beacon messages with their neighbors in geographic forwarding algorithms. The interval at which these nodes broadcast their beacon messages is typically fixed. However, determining an appropriate value for this interval is challenging. A longer interval reduces the number of beacons needed, but may result in significant location errors. Conversely, a shorter interval guarantees more accurate location information, but induces heavier control overheads. Additionally, since a fixed value is assigned to the lifetime of each routing entry, the forwarding algorithm cannot adapt well to different mobility environments. Therefore, this paper presents a dynamic route maintenance algorithm (DRM) for beacon-based geographic routing. In the approach, the mobile nodes dynamically adjust their beacon intervals based on their speed of movement. Moreover, the routing information can be well managed using the mobility prediction. The simulation results show that DRM not only significantly decreased the routing overheads in a low mobility scenario but also guaranteed the high quality packet delivery in high mobility environments.     

A stable weight-based on-demand routing protocol for mobile ad hoc networks

A mobile ad hoc network (MANET) consists of a set of mobile hosts that can communicate with each other without the assistance of base stations. In MANETs, the high mobility of mobile nodes is a major reason for link failures. In this paper, we propose a stable weight-based on-demand routing protocol (SWORP) for MANETs. The proposed scheme uses the weight-based route strategy to select a stable route in order to enhance system performance. The weight of a route is decided by three factors: the route expiration time, the error count, and the hop count. Route discovery usually first finds multiple routes from the source node to the destination node. Then the path with the largest weight value for routing is selected. Simulation results show that the proposed SWORP outperforms DSR, AODV, and AODV-RFC, especially in a high mobility environment.     

A clique-based secure admission control scheme for mobile ad hoc networks (MANETs)

Wireless mobile ad hoc networks (MANETs) do not have centralized infrastructure and it is difficult to provide authentication services. In this paper, we apply Certificate Graph (CG) and identity-based security in designing an admission control scheme for MANETs. We first use one-hop message exchange to build CG at each mobile node. Then we select maximum clique nodes in CG as distributed Certificate Authorities (CAs). We use identity-based key agreement from pairings to protect each session. Then we prove the security by Canetti–Krawczyk (CK) model-based analysis. We demonstrate the effectiveness and feasibility of our protocol through computer simulations.     

Location aware, dependable multicast for mobile ad hoc networks

This paper introduces dynamic source multicast (DSM), a new protocol for multi-hop wireless (i.e., ad hoc) networks for the multicast of a data packet from a source node to a group of mobile nodes in the network. The protocol assumes that, through the use of positioning system devices, each node knows its own geographic location and the current (global) time, and it is able to efficiently spread these measures to all other nodes. When a packet is to be multicast, the source node first locally computes a snapshot of the complete network topology from the collected node measures. A Steiner (i.e., multicast) tree for the addressed multicast group is then computed locally based on the snapshot, rather than maintained in a distributed manner. The resulting Steiner tree is then optimally encoded by using its unique Pr

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u" height="11" width="9">fer sequence and is included in the packet header as in, and extending the length of the header by no more than, the header of packets in source routing (unicast) techniques. We show that all the local computations are executed in polynomial time. More specifically, the time complexity of the local operation of finding a Steiner tree, and the encoding/decoding procedures of the related Prüfer sequence, is proven to be O(n²), where n is the number of nodes in the network. The protocol has been simulated in ad hoc networks with 30 and 60 nodes and with different multicast group sizes. We show that DSM delivers packets to all the nodes in a destination group in more than 90% of the cases. Furthermore, compared to flooding, DSM achieves improvements of up to 50% on multicast completion delay.     

A comparative evaluation of intrusion detection architectures for mobile ad hoc networks

Mobile Ad Hoc Networks (MANETs) are susceptible to a variety of attacks that threaten their operation and the provided services. Intrusion Detection Systems (IDSs) may act as defensive mechanisms, since they monitor network activities in order to detect malicious actions performed by intruders, and then initiate the appropriate countermeasures. IDS for MANETs have attracted much attention recently and thus, there are many publications that propose new IDS solutions or improvements to the existing. This paper evaluates and compares the most prominent IDS architectures for MANETs. IDS architectures are defined as the operational structures of IDSs. For each IDS, the architecture and the related functionality are briefly presented and analyzed focusing on both the operational strengths and weaknesses. Moreover, methods/techniques that have been proposed to improve the performance and the provided security services of those are evaluated and their shortcomings or weaknesses are presented. A comparison of the studied IDS architectures is carried out using a set of critical evaluation metrics, which derive from: (i) the deployment, architectural, and operational characteristics of MANETs; (ii) the special requirements of intrusion detection in MANETs; and (iii) the carried analysis that reveals the most important strengths and weaknesses of the existing IDS architectures. The evaluation metrics of IDSs are divided into two groups: the first one is related to performance and the second to security. Finally, based on the carried evaluation and comparison a set of design features and principles are presented, which have to be addressed and satisfied in future research of designing and implementing IDSs for MANETs.     

Signal strength based routing for power saving in mobile ad hoc networks

The transmission bandwidth between two nodes in mobile ad hoc networks is important in terms of power consumption. However, the bandwidth between two nodes is always treated the same, regardless of what the distance is between the two nodes. If a node equips a GPS device to determine the distance between two nodes, the hardware cost and the power consumption increase. In this paper, we propose using a bandwidth-based power-aware routing protocol with signal detection instead of using GPS devices to determine the distance. In our proposed routing protocol, we use the received signal variation to predict the transmission bandwidth and the lifetime of a link. Accordingly, the possible amount of data that can be transmitted and the remaining power of nodes in the path after data transmission can be predicted. By predicting the possible amount of data that can be transmitted and the remaining power of nodes after data transmission, we can design a bandwidth-based power-aware routing protocol that has power efficiency and that prolongs network lifetime. In our simulation, we compare our proposed routing protocol with two signal-based routing protocols, SSA and ABR, and a power-aware routing protocol, MMBCR, in terms of the throughput, the average transmission bandwidth, the number of rerouting paths, the path lifetime, the power consumed when a byte is transmitted, and the network lifetime (the ratio of active nodes).     

Middleware support for service discovery in special operations mobile ad hoc networks

Technology can play a significant role in the management and coordination activities of special operations such as emergency response, military combat missions, forest firefighting, etc. Mobile ad hoc networks (MANETs) can be used quite effectively to manage resource sharing in such operations due to their flexibility and ease of establishment. The concept of service discovery has some appealing characteristics and features that can be adopted and adapted for the nature and needs of these applications. In this study, we present the middleware architecture of a service discovery and allocation system that we propose for the applications of special operations. The main purpose of the proposed system is to locate, reserve and assign a certain service to the party that is in need of this service, with little or no human intervention. The concerned service could be medics, equipment, ambulances, etc. The network participants are divided into service providers, service requestors and anchor nodes. The anchor nodes are the ones which are used to manage resource discovery and allocation. The proposed middleware takes into consideration the classification of these network nodes on the basis of their function. Based on the classification of a certain node, only the middleware modules relevant to its function are activated. We describe the design of this middleware in detail. We also experiment with the proposed technique and present some results that show its capabilities from different performance perspectives.     

移动Ad hoc网基于信任度的路由发现算法

在研究信任关系的基础上,介绍信任度的概念,同时提出一种信任度的计算方法,将主观判断和第三方认证结合起来得出节点间的信任关系,并在此基础上实现一种安全、灵活的信任管理机制和路由选择算法。通过仿真实验结果证明,该方法可以有效地提高路由协议的安全性能。     

Performance evaluation of dynamic probabilistic broadcasting for flooding in mobile ad hoc networks

In mobile ad hoc networks (MANETs), flooding is a required message dissemination technique for network-wide broadcast. The conventional blind flooding algorithm causes broadcast storm problem, a high number of unnecessary packet rebroadcasts thus resulting in high contention and packet collisions. This paper proposes a new probabilistic approach that dynamically fine-tunes the rebroadcasting probability of a node for routing request packets (RREQs) according to the number of neighbour nodes. We evaluate the performance of the proposed approach for the ad hoc on demand distance vector (AODV) routing protocol and compared against the blind flooding, fixed probabilistic and adjusted probabilistic flooding [L.M.M.M. Bani-Yassein, M. Ould-Khaoua et al., Performance analysis of adjusted probabilistic broadcasting in mobile ad hoc networks, International Journal of Wireless Information Networks 13(2) (2006) 127–140; M.B. Yassein, M.O. Khaoua et al., Improving route discovery in on-demand routing protocols using local topology information in MANETs, Proceedings of the ACM international workshop on Performance Monitoring, Measurement, and Evaluation of Heterogeneous Wireless and Wired Networks, Terromolinos, Spain, ACM Press, 2006, pp. 95–99.] approaches. The simulation results show that our proposed approach demonstrates better performance than blind flooding, fixed probabilistic and adjusted flooding approaches.     

Cost-effective mobile ad hoc networks management

As there are more and more mobile devices in use, different mobile networking models such as ad hoc or mesh are attracting a large research interest. Self-organizing mobile ad hoc networks (MANET) allow devices to share their services and resources without any central administration or Internet support. In this respect they can become the backbone of the wireless grid or the gateway to existing grids. To achieve these goals, MANET management must be as effective as that of wired networks. This is, however, a challenging task due to network features like mobility, heterogeneity, limited resources of hosts and feeble communication. This paper presents a set of simple, cost-effective and resilient procedures for the basic tasks of MANET creation and management.     

层状 Ad Hoc 网络的信息传播路由算法研究

讨论了层状移动AdHoc网络的一个信息传播路由算法和基于半马尔可夫过程的节点移动跟踪模型,通过该路由算法可以有效地解决层状子网络间的通信和信息交换。通过路由算法得到的中继节点的移动跟踪模型和计算机仿真,分析了层状移动AdHoc网络的传播性能和路由开销,并得出:当 0≤ρ≤ 1时,层状AdHoc网络的传播性能显著地受到移动呼叫率ρ的影响,当ρ>1时,层状AdHoc网络的传播性能主要取决于移动网络的节点总数、节点移动速度和加速度的结论。