一种用于移动自组控制网络的QoS路由

为更好地将移动自组网络用于网络控制系统（NCS）,结合NCS的网络特性,提出了一种基于链路信号质量的QoS路由算法。主要QoS机制包括根据接收信号强度选择较稳定的路由;用Hello报文广播节点的预留带宽;中间节点为所有受影响的数据流修复路由、目的节点向源节点广播路由修复报文进行路由修复。NS2仿真表明当节点移动性强时,该QoS路由算法可有效减少网络的平均端到端时延和丢包率,提高控制系统稳定性。     

Energy Based Random Repeat Trust Computation in Delay Tolerant Network

As the use of mobile devices continues to rise, trust administration will significantly improve security in routing the guaranteed quality of service (QoS) supply in Mobile Ad Hoc Networks (MANET) due to the mobility of the nodes. There is no continuance of network communication between nodes in a delay-tolerant network (DTN). DTN is designed to complete recurring connections between nodes. This approach proposes a dynamic source routing protocol (DSR) based on a feed-forward neural network (FFNN) and energy-based random repetition trust calculation in DTN. If another node is looking for a node that swerved off of its path in this situation, routing will fail since it won’t recognize it. However, in the suggested strategy, nodes do not stray from their pathways for routing. It is only likely that the message will reach the destination node if the nodes encounter their destination or an appropriate transitional node on their default mobility route, based on their pattern of mobility. The EBRRTC-DTN algorithm (Energy based random repeat trust computation) is based on the time that has passed since nodes last encountered the destination node. Compared to other existing techniques, simulation results show that this process makes the best decision and expertly determines the best and most appropriate route to send messages to the destination node, which improves routing performance, increases the number of delivered messages, and decreases delivery delay. Therefore, the suggested method is better at providing better QoS (Quality of Service) and increasing network lifetime, tolerating network system latency.     

Black Hole Attack Detection and Performance Improvement in Mobile Ad-Hoc Network

ABSTRACT

Security is an essential service for mobile network communications. Routing plays an important role in the security of mobile ad-hoc networks (MANETs). A wide variety of attacks targets the weakness of MANETs. By attacking the routing protocols, attackers can absorb network traffic, injecting themselves into the path between the source and destination. The black hole attack is one of the routing attacks where a malicious node advertise itself as having the shortest path to all nodes in the network by sending fake route reply. In this paper, a defense scheme for detecting black hole node is proposed. The detection is based on the timing information and destination sequence numbers maintained in the Neighborhood Route Monitoring Table. The table maintains the record of time of Reply. A black hole node will send a route reply message without checking the routing table as the legitimate node normally does. This reduced reply time is used to detect the black hole node. To improve the security further, the destination sequence number is checked with the threshold value, which is dynamically updated. The simulation results demonstrate that the protocol not only detects black hole attack but also improves the overall performance.     

Efficient route optimization scheme for nested-NEMO

Network mobility (NEMO) basic support protocol maintains the connectivity when mobile router (MR) of a mobile network changes its point of attachment to the Internet by establishing a bi-directional tunnel between the MR and the home agent (HA). A packet from a correspondent node (CN) traverses through the tunnel to reach the mobile network. Nesting occurs in NEMO when a MR's new attachment point is in another mobile network that has also moved away from its home link. The level of tunneling increases as the level of nesting increases. Multiple levels of tunneling in nested NEMO adds multiple legs to a non-optimized routing path that the IP packets have to traverse in order to reach the final destination. As per our study, an efficient route optimization technique in NEMO, particularly in nested NEMO, is still a research challenge. In this paper, we propose an efficient route optimization scheme for nested NEMO. We use two care-of Addresses for each MR, as well as two types of entries, such as fixed and visiting, in the routing table in each MR. Our route optimization scheme removes the tunnels completely from the nested NEMO in a single step using only one binding update message irrespective of the number of levels in the nest. Our route optimization scheme also works for non-nested NEMO.     

一种移动IP的外部代理分层模型--Step-HMIP

现有的移动IP规范存在两个重要的性能问题：(1)通信对端和外地链路上的移动节点之间的三角路由问题;(2)移动节点在紧密耦合的小蜂窝基站间频繁切换时会增加网络负载并加重数据包的丢失．该文针对这两个问题进行研究,给出了一个基于基本移动IP规范的外部代理分层模型——Step-HMIP模型．在此模型中引入了一个新的实体——网关移动代理,用以实现优化路由和平滑切换的功能：在NS上建立了Step-HMIP的仿真模型,对模型的主要参数测试结果表明．Step—HMIP模型在对属地代理(HA)、固定的通信对端(如Web服务器和FTP服务器)和对网络层以上协议无需进行改动的情况下．以小的配置代价就可显著优化路由,降低属地代理的注册负载和稳定了切换时的数据传输率．     

移动ad hoc网络AODV协议的分析与改进

由于移动ad hoc网络的AODV（Ad hoc on-Demand Distant Vector）协议仅维护1条到目的节点的路由记录,即使路由未失效,在超时后也会被删除,因此提出改进的AODV协议---HI-AODV协议.改进内容为：（1）借鉴DSR协议的特点,使其路由表维护多条路由记录;（2）在路由发现和路由维护中有效利用路由缓存信息和多路径路由,使得路由发现更加迅速.仿真结果表明HI-AODV协议可以提高数据吞吐量,减小平均延时.但由于移动ad hoc网络节点的移动性,采用HI-AODV协议容易导致路由信息失效,对路由协议产生负面影响.     

Detection of blackhole attack in a Wireless Mesh Network using intelligent honeypot agents

A Wireless Mesh Network (WMN) is a promising way of providing low-cost broadband Internet access. The underlying routing protocol naively assumes that all the nodes in the network are non-malicious. The open architecture of WMN, multi-hop nature of communication, different management styles, and wireless communication paves way to malicious attackers. The attackers can exploit hidden loopholes in the multipath mesh routing protocol to have a suction attack called the blackhole attack. The attacker can falsify routing metrics such as the shortest transmission time to reach any destination and thereby suck the network traffic. We propose a novel strategy by employing mobile honeypot agents that utilize their topological knowledge and detect such spurious route advertisements. They are deployed as roaming software agents that tour the network and lure attackers by sending route request advertisements. We collect valuable information on attacker’s strategy from the intrusion logs gathered at a given honeypot. We finally evaluate the effectiveness of the proposed architecture using simulation in ns-2.     

Supporting mobility with wireless ATM

An implicit assumption underlying most networking research has been that two Internet users would be connected only by fixed links (wire lines). Increased use of portable computers, wireless networks and satellites has generated interest in supporting “computing on the move”, or mobile computing. Instead of maintaining a fixed position in a network, users in this environment are free to roam. Mobile computing raises interesting issues, such as how to route packets as the mobile user (host) moves about and how to guarantee the quality of service (QOS) that an application running on such a mobile host may need. Other issues include the choice of a transport protocol to use on top of a mobile host and how to deal with poor performance in wireless links. There are two possible approaches to supporting mobile computing over the Internet. The first uses a mobile IP (Internet Protocol), whereby packets (datagrams) are forwarded by a designated stationary host to the mobile host. The second approach involves wireless ATM (asynchronous transfer mode), with host mobility supported by rerouting/rearranging the end-to-end ATM connection between mobile and stationary hosts     

一种MANET网络的位置辅助路由协议

Ad-Hoc网络（即MANET）由于节点的移动，导致路由频繁变化．基于位置辅助路由协议（LAR1），本文提出了一种带路径优化的增强LAR1协议（ELAR1）．节点通过在接收到的路由请求包中获取其携带的其它转发节点位置信息，提高发起路由请求时预知目的节点位置的几率，降低网络内路由广播包的数量．针对路由路径中可能存在非最短路由，利用位置信息对获得的路由进行路径优化．仿真结果表明，ELAR1比LAR1有较低的路由请求开销、较高的包投递率和较低的端到端延迟．     

Power-aware localized routing in wireless networks

A cost aware metric for wireless networks based on remaining battery power at nodes was proposed for shortest-cost routing algorithms, assuming constant transmission power. Power-aware metrics, where transmission power depends on distance between nodes and corresponding shortest power algorithms were also proposed. We define a power-cost metric based on the combination of both node's lifetime and distance-based power metrics. We investigate some properties of power adjusted transmissions and show that, if additional nodes can be placed at desired locations between two nodes at distance d, the transmission power can be made linear in d as opposed to d^α dependence for α ⩾ 2. This provides basis for power, cost, and power-cost localized routing algorithms where nodes make routing decisions solely on the basis, of location of their neighbors and destination. The power-aware routing algorithm attempts to minimize the total power needed to route a message between a source and a destination. The cost-aware routing algorithm is aimed at extending the battery's worst-case lifetime at each node. The combined power-cost localized routing algorithm attempts to minimize the total power needed and to avoid nodes with a short battery's remaining lifetime. We prove that the proposed localized power, cost, and power-cost efficient routing algorithms are loop-free and show their efficiency by experiments     

移动IPv6的路由特性分析

移动IPv6是为了使各种移动设备在下一代IP网络间实现无缝漫游而设计发展的路由协议。尽管在移动IPv4中已经解决了节点移动的问题,但由于IPv4本身的限制,它无法解决各种节点和网络移动组合的路由情况。文章在移动IPv6下,不仅对节点移动,还对网络移动的路由特性进行了分析。     

LA_AODV路由协议的仿真与性能分析

AODV协议以源到目的的最短路径或最短跳数作为路由度量参数。LA_AODV协议综合考虑无线移动自组织网络的路由层和物理层，提出了一种新的路由度量参数。首先介绍了LA_AODV协议，然后讲述在NS2中实现LA_AODV的方法，并详细分析仿真中的关键问题。仿真结果表明LA_AODV协议在保持AODV协议特点的基础上，具有吞吐量高、路由开销低、延时小的特点。     

A stability-based distributed routing mechanism to support unicast and multicast routing in ad hoc wireless network

An ad hoc network can be envisioned as a collection of mobile routers, each equipped with a wireless transceiver, which are free to move about arbitrarily. In ad hoc wireless networks, even if two nodes are outside the wireless transmission range of each other, they may still be able to communicate in multiple hops using other intermediate nodes. However, the dynamics of these networks, as a consequence of mobility and disconnection of mobile hosts, pose a number of problems in designing routing schemes for effective communication between any pair of source and destination. In this paper, a stability-based unicast routing mechanism, that considers both link affinity and path stability in order to find out a stable route from source to destination, is proposed. It is then extended to support multicast routing as well where only local state information (at source) is utilized for constructing a multicast tree. The performance of the proposed scheme is evaluated on a simulated environment to show that the stability-based scheme provides a unified framework for both unicast and multicast routing and reduces the probability of route error drastically in both the cases.     

基于NS2的Ad Hoc网络AODV协议研究与改进

无线自组网是由一组无线移动主机组成的无基础设施的临时网络,在与其相关的网络协议的研究中常涉及到修改及扩展问题。文章分析了经典按需路由协议AODV的路由发现和建立过程,通过NS2仿真软件的内核扩展及重编译,在控制台输出相关的扩展内容,包括RREQ和RREP包的传送、正反向路由表的建立和节点路由表的更新等信息。结果表明,在NS2仿真软件下对无线自组网路由协议的研究和调试分析是一种科学有效的方法。最后对AODV协议本身提出了几种改进的思路和方法。     

一种基于范围的可靠移动组播算法

移动IP[1]提出了双向隧道和远程签署两种移动组播算法,各自有明显的优缺点.在以双向隧道为基础的改进算法RBMoM[4]中引入了服务范围的概念.提出移动组播算法在远程签署的基础上结合服务范围概念,寻求最优转发路径和最小组播树管理开销之间的折衷,并在节点移动时采用在移动代理间建立隧道的方式补充数据包,提高组播可靠性.对模拟结果的分析和比较显示该算法具有更好的综合性能.     

移动IP分布式路由优化研究

IETF提出的移动IP协议对微移动的支持不够，而分布式路由方案能较好地解决该问题。该文在一种分布式移动IP方案的基础上进行了改进：将转向代理的缓存修改为循环列表，减少移动节点接收的乱序分组；当切换转向代理时，移动节点向前一个转向代理发送绑定更新消息，减少转向代理切换时的分组丢失；在转向代理处引入Snoop机制，减少通信对端重传分组数。利用NS2软件对两种方案进行了仿真。仿真结果表明，改进的方案能够明显地减少重传分组和乱序分组，进一步减少远程信令流量和数据流量，提高网络资源的利用率，有效地改善移动IP的性能。     

移动Ad Hoc网络中基于移动代理的路由协议

分析了移动Ad Hoc网络现有两类路由协议的优缺点,提出基于移动代理的AODV路由协议。仿真结果表明,该方案通过移动代理的漫游来更新途经节点路由表,大大减少路由请求报文发起数,降低了平均端到端的数据传输时延,网络负载增加不大。     

基于Merkle树的安全移动代理路由协议

移动代理是一种软件程序,它漫游在计算机网络中,经过不同的主机代替用户执行一定的任务。它被认为在未来的电子商务中将起到很重要的作用,但安全问题一直是移动代理得到实际应用的一个很大障碍。本文利用二元Merkle树结合Hash函数给出了一个安全的基于Merkle树的移动代理路由协议。相比原有的嵌套签字加密协议,它显著地降低了移动代理主人的计算复杂度。     

面向MANET云平台应用的多目标蚁群优化AODV路由协议

为增强网络中路由的稳健性,提出了一种优化的AODV路由协议,结合多目标优化和蚁群优化选择最优路由。首先,计算各节点的传输距离、进展、传输延迟、方向和生存时间5个度量;然后,以传输距离、传输延迟和方向3个度量的最小化,以及进展和生存时间两个度量的最大化为优化目标,构造蚁群算法中的移动概率函数,并结合局部最优路径更新全局信息素;此后,在AODV路由协议的基础上,选择移动概率最大的节点作为最佳下一跳节点,生成最优路由。最后,在部署的大学区实验云模型平台上进行了验证。仿真结果表明,与AODV和EN-AODV路由协议相比,新路由协议的报文送达率更高,同时端到端的平均时延和路由开销更小。