一种解决ad hoc网络中自私节点安全问题的方法

移动ad hoc网络（MANET）路由和分组转发功能需要节点间的相互合作，自私节点为节约能量而不参与合作，将会影响网络的正常工作．因此本文将针对自私节点危害和解决方法展开分析，并提出一种改进解决方法——基于可信任中心服务器和邻居监测的合作增强机制，该方法不但能够激励节点间的相互合作，而且有效地解决了自私节点改变用户身份的欺骗攻击．最后，仿真结果表明这种合作增强机制对自私节点安全问题是有效的，并且易于实用化．     

移动ad hoc网络安全综述

移动ad hoc网络是由移动节点自组织形成的网络,由于其动态拓扑、无线通信的特点,容易遭受各种安全威胁.该文介绍了移动ad hoc网络安全研究的最新研究进展.首先从传输信道、移动节点、动态拓扑、安全机制、路由协议几方面,分析了移动ad hoc网络的安全弱点,然后将移动ad hoc网络安全方面的研究分为三个方向:密钥分配与管理、入侵检测、增强合作.对每个方向内一些典型安全方案也进行了分类论述,同时分析了各种方案的优点和缺点,并进行了综合比较.文中阐明了目前协议存在的一些问题并提出了相应的改进方法,最后指出了下一步研究方向.     

利用ad hoc网络实现下一代移动互联

随着ad hoc网络的研究工作的发展,以Internet接入为代表的ad hoc网络的应用问题越来越被人们所关注.在本文中,我们提出了一个将ad hoc网络和移动IPv6相结合的方案,首先将基于动态源路由(dynamic source routing,DSR)的MANET升级到IPv6使其能够接入6Bone网,并通过搭建测试床进行了验证和测量;在此基础上,又提出了移动IPv6的兼容方案,并通过仿真对其在不同环境下的性能进行了验证.     

移动ad hoc网络预分配非对称密钥管理方案

为了降低移动ad hoc网络非对称密钥管理中的通信开销,基于组合公钥思想,将ElGamal方案与预分配密钥方式相结合,提出一种基于身份的预分配非对称密钥管理方案(PAKMS)。该方案通过私钥生成中心为节点预分配主密钥子集及基于时间获得节点密钥更新的方式,从方法上降低了移动ad hoc网络非对称密钥管理中的通信开销;私钥生成中心为节点预分配主密钥子集的方式也使节点在网络运行阶段不再依赖私钥生成中心为节点分配和更新密钥。由此,弱化了基于身份密钥管理中存在的私钥托管问题对网络安全的影响。与典型方案对比分析表明,该方案在提供节点密钥更新服务的情况下能够有效降低网络通信开销。此外,对方案的安全性进行了详细证明。     

IPv6移动ad hoc网络与Internet互联中的网关发现

前言 Ad hoc是一种特殊的无线网络应用模式,是由两个或者多个具有无线通信能力和组网能力的设备组成的集合.这些通信设备可以与在它们通信范围之内或之外的另一个设备进行通信,无需通过接入点.     

基于朋友机制的移动ad hoc网络路由入侵检测模型研究

从如何有效检测移动ad hoc网络路由入侵行为、如何准确地响应并将恶意路由节点移除网络,提供可信路由环境的角度进行分析,提出了一种基于朋友机制的轻量级移动ad hoc网络入侵检测模型,并以典型的黑洞攻击为例,通过OPNET网络建模仿真及实验分析,验证了该模型的可行性和有效性。     

在ad hoc网络中一种新的节能路由切换模型

提出了一种基于能量消耗的路由切换模型(ERHM),它在路由维护中利用切换技术来使路由的能量消耗最小.仿真结果表明采用切换技术的ERHM模型的能量节省量要比不采用切换技术节约1.5～7.5倍,且节点的移动性越大,能量节约越多.     

面向无线ad hoc网络的一种平面t-支撑图

拓扑控制算法的目标是为无线ad hoc网络确定合适的底层拓扑。在无线ad hoc网络中，几何路由协议是一类重要的路由协议，为了保证消息转发的可达性和限制路由长度，它要求底层拓扑满足连通性、平面性和稀疏性，并且是原拓扑的t-支撑图。本文提出了一种新的几何结构AUDel图，并提出了两种低通信开销的构造AUDel图的局部拓扑控制算法。理论分析表明，AUDel图满足上述要求，我们提出的拓扑控制算法的通信歼销小于其它构造平面t-支撑图的拓扑控制算法。模拟实验验证了以上结论。     

基于双信道的一种ad hoc网络路由策略

利用多个信道接口来改善ad hoc网络信道容量。即一个信道周期性的广播节点状态信息分组来维护全网所有节点的状态信息，而另一个信道利用此信息采用最短路径搜寻算法来获得到目的节点的路由并完成数据传输。这样充分结合了表驱动路由方法和按需式路由方法的优点。另外，信息维护与数据分组分别在两个信道内同时进行，避免了信息维护对数据分组传输的影响，提高了网络性能。     

基于移动预测模型的ad hoc网络稳定链路度量

提出了一种基于移动预测模型的稳定链路度量算法，定义了稳定邻居度量和本地运动度量2种测度。根据这2种测度，移动预测模型利用LZ78算法对本地节点与其邻居的稳定性概率进行预测，从而找到其最稳定邻居，为选择稳定路由提供依据。仿真结果表明此算法明显优于直方图算法及最小ID算法，所选链路的稳定性能显著提高。     

Service discovery in mobile ad hoc networks: an overall perspective on architectural choices and network layer support issues

Service discovery is indispensable to ad hoc networking where establishing a stand-alone and self-configurable communication environment is the main objective. In this paper, we first discuss possible service discovery architectures along with the required network support for their implementation in mobile ad hoc networks. We then propose a distributed service discovery architecture that relies on a virtual backbone for locating and registering available services within a dynamic network topology. Our proposal consists of two independent components: (i) formation of a virtual backbone and (ii) distribution of service registrations, requests, and replies. The first component creates a mesh structure from a subset of a given network graph that includes the nodes acting as service brokers and also a subset of paths (which we refer to as virtual links) connecting them. Service broker nodes (SBNs) constitute a dominating set, i.e. all the nodes in the network are either in this set or only one-hop away from at least one member of the set. The second component establishes sub-trees rooted at service requesting nodes and registering servers for efficient dissemination of the service discovery control messages. Extensive simulation results are provided for comparison of performance measures, i.e. latency, success rate, and control message overhead, when different architectures and network support mechanisms are utilized in service discovery.     

ad hoc网络地址自动配置技术研究

针对ad hoc网络的地址自动配置问题,介绍了该领域研究现状和最新进展,以及有代表性的配置机制的配置思想和实施方法,比较了各配置机制的相关性能,在此基础上给出了结论.     

基于HELLO机制的MANET与Internet高效互联

文章提出一种基于AODV HELLO机制的移动自组网与Internet互联方案。该方案直接在AODV HELLO分组中包含网关信息以及相邻节点列表．从而在无需引入额外控制分组的前提下进行网关发现并同时避免了在路由计算中引入单向链路。结合使用高效的半隧道转发机制，使得互联性能得到显著提升而开销合理，基于NS2的仿真结果显示了其有效性。     

Cluster-Based Autoconfiguration for Mobile Ad hoc Networks

IP address autoconfiguration of mobile nodes is highly desirable in the practical usage of most mobile ad hoc networks (MANETs). This paper proposes cluster-based autoconfiguration, a novel approach for the efficient address autoconfiguration of MANETs. The cluster structure derived from clustering techniques is used to manage address assignment and conflict resolution. By introducing the concept of virtual address agents (AAs), the proposed approach can be applicable to many existing clustering protocols. Finally, analysis and simulation demonstrate that the proposed scheme outperforms the previous autoconfiguration approaches.

Mobile ad hoc cloud: A survey

The unabated flurry of research activities to augment various mobile devices in terms of compute‐intensive task execution by leveraging heterogeneous resources of available devices in the local vicinity has created a new research domain called mobile ad hoc cloud (MAC) or mobile cloud. It is a new type of mobile cloud computing (MCC). MAC is deemed to be a candidate blueprint for future compute‐intensive applications with the aim of delivering high functionalities and rich impressive experience to mobile users. However, MAC is yet in its infancy, and a comprehensive survey of the domain is still lacking. In this paper, we survey the state‐of‐the‐art research efforts carried out in the MAC domain. We analyze several problems inhibiting the adoption of MAC and review corresponding solutions by devising a taxonomy. Moreover, MAC roots are analyzed and taxonomized as architectural components, applications, objectives, characteristics, execution model, scheduling type, formation technologies, and node types. The similarities and differences among existing proposed solutions by highlighting the advantages and disadvantages are also investigated. We also compare the literature based on objectives. Furthermore, our study advocates that the problems stem from the intrinsic characteristics of MAC by identifying several new principles. Lastly, several open research challenges such as incentives, heterogeneity‐ware task allocation, mobility, minimal data exchange, and security and privacy are presented as future research directions. Copyright © 2016 John Wiley & Sons, Ltd.     

定向Ad hoc网络中一种带冲突避免的邻居发现算法

定向天线应用于ad hoc网络,一方面能显著提升网络性能,另一方面也需要新的MAC和路由协议来控制定向天线系统。邻居发现算法作为其中最重要的协议之一,是定向ad hoc网络组网的基础和前提,针对现有文献中提出的各种邻居发现算法大多没有考虑同一定向波束扇区内存在多个节点时的冲突情况,提出一种带冲突避免的定向邻居发现算法DAND/CA。DAND/CA通过随机选择发送控制消息占用的微时隙,能有效避免碰撞冲突的发生。仿真结果表明,提出的DAND/CA算法在邻居发现时间和成功率等方面明显优于现有算法。     

Stimulating Node Cooperation in Mobile Ad hoc Networks

Mobile Ad hoc Networks (MANETs) rely on the cooperation of nodes for packet routing and forwarding. Much of the existing work in MANETs assume that mobile nodes (possibly owned by selfish users) will follow prescribed protocols without deviation. However, a user may misbehave due to several advantages resulting from noncooperation, the most obvious being power saving. As such, the network availability is severely endangered. Hence, enforcing the cooperation among nodes becomes a very important issue. Several different approaches have been developed to detect non-cooperative nodes or deal with the non-cooperative behavior of mobile nodes in MANETs. These protocols are first surveyed in details in this paper. It is found that the proposed approaches have several concerns that prevent them from really enforcing the node cooperation in MANETs. Thus, a new scheme that can stimulate and also enforce nodes to cooperate in a selfish ad hoc environment is presented. We also present a mechanism to detect and exclude potential threats of selfish mobile nodes. The simulation results indicate that by using the proposed scheme, MANETs can be robust against nodes’ misbehaving and the performance of the network is enhanced many folds when compared to other existing schemes.

A routing protocol based on node density for ad hoc networks

Ad hoc networks are a type of mobile network that functions without any fixed infrastructure. One of the weaknesses of ad hoc networks is that a route used between a source and a destination is likely to break during communication. To solve this problem, one approach consists of selecting routes whose nodes have the most stable behavior. Another strategy aims at improving the route repair procedure. This paper proposes a method for improving the success rate of local route repairs in mobile ad hoc networks. This method is based on the density of the nodes in the neighborhood of a route and on the availability of nodes in this neighborhood. Theoretical computation and simulation results show that the data packet loss rate decreased significantly compared to other methods which are well-documented in the literature. In addition, the time required to complete a local route repair following a failure was significantly reduced.     

An immunity-based security architecture for mobile ad hoc networks

This paper focuses on investigating immunological principles in designing a multi-agent security architecture for intrusion detection and response in mobile ad hoc networks. In this approach, the immunity-based agents monitor the situation in the network. These agents can take appropriate actions according to the underlying security policies. Specifically, their activities are coordinated in a hierarchical fashion while sensing, communicating, decision and generating responses. Such an agent can learn and adapt to its environment dynamically and can detect both known and unknown intrusions. The proposed intrusion detection architecture is designed to be flexible, extendible, and adaptable that can perform real-time monitoring. This paper provides the conceptual view and a general framework of the proposed system. In the end, the architecture is illustrated by an example to show it can prevent the attack efficiently.     

Contention-based forwarding for mobile ad hoc networks

Existing position-based unicast routing algorithms which forward packets in the geographic direction of the destination require that the forwarding node knows the positions of all neighbors in its transmission range. This information on direct neighbors is gained by observing beacon messages each node sends out periodically.

Due to mobility, the information that a node receives about its neighbors becomes outdated, leading either to a significant decrease in the packet delivery rate or to a steep increase in load on the wireless channel as node mobility increases. In this paper, we propose a mechanism to perform position-based unicast forwarding without the help of beacons. In our contention-based forwarding scheme (CBF) the next hop is selected through a distributed contention process based on the actual positions of all current neighbors. For the contention process, CBF makes use of biased timers. To avoid packet duplication, the first node that is selected suppresses the selection of further nodes. We propose three suppression strategies which vary with respect to forwarding efficiency and suppression characteristics. We analyze the behavior of CBF with all three suppression strategies and compare it to an existing greedy position-based routing approach by means of simulation with ns-2. Our results show that CBF significantly reduces the load on the wireless channel required to achieve a specific delivery rate compared to the load a beacon-based greedy forwarding strategy generates.