Ad hoc网络中的多径路由发现策略

针对如何在Ad hoc网络中选择多路径的问题,对备份源路由协议进行改进。在路由发现过程中综合考虑网络的链路服务时间和传输延迟,引入一个因子,用于选择一条主路径,采用改进的成本函数选出一条与主路径相关性较小的路径作为备份路径,用主路径和备份路径组成的路由对发送数据包。实验结果表明,改进后的协议能减少路由发现次数,提高路由可靠性和网络性能。     

能量感知的无线传感器网络多路径路由研究

针对现有多路径路由协议AOMDV的不足,提出了适用于无线传感器网络的能量感知多路径路由协议IMEA.IMEA在建立链路不相关的多路径时能优先建立节点不相关的多路径,在主路径失效时能优先选择与主路径共用节点最少的作为次优路径,而能量感知的路径选择策略能均衡网络中节点的能量消耗,实现数据传输路径的低能耗.对IMEA进行了仿真实验,结果表明IMEA有效延长了网络的生存时间.     

一种工业物联网多路径可靠路由机制

为了满足工业物联网对数据传输的可靠性需求,提出了一种多路径可靠路由机制.结合边缘计算和软件定义网络的思想,构建了新型的工业物联网模型.在此基础上,该机制针对突发性和周期性数据的不同可靠性需求,分别设计了相应的路由策略,并采用可靠性模型评估源和目的节点之间路径的可靠性,确定满足工业应用需求的多条路径信息.接下来,源节点按照路径信息将工业数据传输到目的节点.当节点的能量和负载以及链路质量信息发生变化时,该机制根据最新的全局视图动态地调整路由决策,从而提高网络性能.仿真实验结果表明,该路由机制在数据传输的可靠性和网络的可扩展性方面表现出了较好的性能.     

认知无线电网络备份路由协议研究

在认知无线电网络,由于非干扰性要求,次用户使用的频段会意外被主用户抢占.这种频段抢占可能频繁发生,它给可靠通信带来巨大的影响.提出一种面向可靠路由的备份路由协议,该协议将机会频谱、链路中断及节点失效考虑在内.仿真实验表明,所提出的新协议能有效地克服间歇连接、减小路由开销和提高数据传输的有效负载.     

邻居认证的Mesh网络安全多路径路由协议

Mesh网络节点的移动性和数据传输的多跳性,使得路由协议的质量以及安全性成为衡量Mesh网络性能的关键因素,迫切需要一种能适应网络拓扑变化,高效、安全的路由协议。而目前针对Mesh网络的路由协议很少考虑到协议本身的安全性问题。提出了一种基于认证的节点分离安全多路径路由协议,在多路径的建立过程中加入了安全机制。分析表明,该路由算法在提供负载平衡、提高整体吞吐量、增加容错性的基础上能够很好地保证路由协议的安全性,而且多路径之间节点分离能够降低链路断开的概率,为数据传输提供更高的可靠性。     

无线传感器网络一种不相交路径路由算法

无线传感器网络经常被用来采集物理数据,监测环境变化.由于低功耗无线通信不确定性、链路质量不稳定性以及节点失效等问题,传感器网络很容易导致路由数据包丢失.为了提高网络路由的可靠性,人们提出多路径路由算法.多路径路由中源节点到目的节点的多条路径可能含有公共节点,或者公共边,如果公共节点或者公共链路失效,则这个数据包也丢失,因此又有人提出不相交多路径路由算法.不相交多路径路由算法又分为链路不相交多路径路由算法和节点不相交多路径路由算法.提出了一种不相交路径路由算法,可以将感知节点采集到的数据通过不相交路径传送到汇聚节点,提高路由的可靠性.而且,这个算法还可以很方便地应用到多Sink节点的网络当中.该路由算法用到的路由表大小为|K|,其中|K|表示路径数.算法的运行时间复杂度是O(|L|),其中|L|表示网络中的边数.     

Ad hoc网络节点不相交多路径距离矢量路由协议

AMR算法是Ad hoc网络计算节点不相交最大路径集合的累积多路径路由机制。针对节点不相交多路径源路由协议MNVP及SMNVP存在的问题,整合按需距离矢量路由AODV和AMR算法,提出了节点不相交多路径距离矢量路由协议MDVRo MDVR协议建立的路径信息分布在网络节点中,可缩短路由分组长度以及减轻路由发现源节点建立路由的负担;可防止攻击者通过墓改路由消息中的路径信息攻陷协议。     

采用角度因子的蚁群优化多路径路由算法

为均衡能量消耗、提高数据传输的可靠性,提出采用角度因子的蚁群优化多路径路由算法（ACOMP）。在密度递减节点部署策略的基础上,为避免能量“热区”,优化蚁群算法进行多路径搜索,搜索过程加入节点间的角度因子进行路径方向引导。基于对选出的各较优路径实时能量的感知,建立多路径决策模型,使得源节点可以选择当前性能最好的路径进行较可靠的数据传输。同时为避免路由空洞,定义修复蚂蚁并结合反馈机制使得路径保持良好状态。仿真结果表明：提出的算法可以实现节能、可靠的路由,并可均衡整个网络的能量消耗。     

煤矿无线传感器网络可靠数据传输协议

针对煤矿无线传感器网络数据流特点,设计了一种基于节点地理位置信息、集成MAC和路由的无线传感器网络可靠数据传输协议。该协议采用概率性唤醒工作方式,根据本地节点的连通度、节点自身的剩余能量信息和区域事件发生概率选择转发节点,同时引入备用节点,在主节点发生故障时自动转换为主节点进行数据转发,保证数据可靠传输。仿真结果表明,该协议能够降低无线传感器网络节点能量消耗,保证数据传输的实时性,提高数据传输的可靠性。     

分组无线网缠绕多路径数据路由协议仿真

在分组无线网的路由协议中,传统路由协议在恶意节点数目较多时网络吞吐量较低,因此提出一种分组无线网缠绕多路径数据路由协议,利用获取的源节点数量信息与位置信息进行路由发现;根据路由发现结果建立从汇聚节点至源节点之间的路径,从而建立缠绕多径路由;对缠绕多径路由进行建簇与重构;进行支路径数优化,从而实现分组无线网缠绕多路径数据路由协议的构建。为了验证上述路由协议的网络吞吐量,将路由协议与基于链路状态的主动式多路径路由协议、基于动态源的按需式多路径路由协议、基于距离矢量的混合式多路径路由协议进行对比,上述四种路由协议在恶意节点数目为30时的网络吞吐量分别为69.5%、33.5%、23.6%、4.2%,通过比较可知,新提出的路由协议的网络吞吐量最高,证明了新路由协议的性能。     

中心计算的无线传感器网络2-不相交路径路由算法

在多路径路由(multipath routing, MPR)算法中,不相交多路径路由(disjoint multipath routing, DMPR)算法具有更高的可靠性和容错性.DMPR算法面临的主要挑战有2点：不相交路径的选优问题和数据包在不相交路径上的传输问题.针对某些工业应用(例如矿井环境监测)中网络拓扑比较稳定,sink节点运算和存储能力较强等特点,提出了一种中心计算的2-不相交路径路由算法——CCDMPR算法.算法利用全网信息计算出从源节点到sink节点的近似最优2-节点(链路)不相交路径,然后生成仅包含主父交节点,辅父节点对和路径比特序列的微路由表并下传到每个节点;针对中心计算方式对链路状态变化的反应迟缓问题,采用了一种中心调度的自适应机制提高路径维护的灵活性.实验结果证明,CCDMPR算法能够显著减小平均路径长度,节省网络整体能量,并能提高数据传输的可靠性.     

Study of network survivability based on multi-path routing mechanism

As an important secure routing mechanism, multi-path routing is one of the major ways to improve network efficiency and to guarantee the network security, which ensures the reliability of data transmission by using backup paths when the primary one is unavailable due to local node or link failures. Most current studies on multi-path routing mechanism are based on experiments or simulations. The resulta are usually specific application scenarios oriented heuristic algorithms, lacking universal significance. In this paper, a theoretic analysis is performed on the relationship between the multi-path routing policy, the network efficiency and its survivability. Starting with point-to-point communication network, an impactoriented analysis is made on the network interference under multi-path routing mechanism. Based on the analysis, the upper-limit of network performance under interference impact is also discussed.     

Energy-efficient multipath routing in wireless sensor network considering wireless interference

Due to the energy and resource constraints of a wireless sensor node in a wireless sensor network (WSN), design of energy-efficient multipath routing protocols is a crucial concern for WSN applications. To provide high-quality monitoring information, many WSN applications require high-rate data transmission. Multipath routing protocols are often used to increase the network transmission rate and throughput. Although large-scale WSN can be supported by high bandwidth backbone network, the WSN remains the bottleneck due to resource constraints of wireless sensors and the effects of wireless interference. In this paper, we propose a multipath energy-efficient routing protocol for WSN that considers wireless interference. In the proposed routing protocol, nodes in the interference zone of the discovered path are marked and not allowed to take part in the subsequent routing process. In this way, the quality of wireless communication is improved because the effects of wireless interference can be reduced as much as possible. The network load is distributed on multiple paths instead of concentrating on only one path, and node energy cost is more balanced for the entire wireless network. The routing protocol is simulated in NS2 software. Simulation result shows that the proposed routing protocol achieves lower energy cost and longer network lifetime than that in the literature.     

Backup reliability of stochastic imperfect-node computer networks subject to packet accuracy rate and time constraints

In a real-time computer network, arcs and nodes have multi-state capacity, lead time, and packet accuracy rate (PAR). Evaluating the reliability of a network whose nodes are imperfect is complex, because node failure results in the disablement of adjacent arcs. Such a network is named a stochastic imperfect-node computer network (SINCN). Under the strict assumption that each arc has a deterministic capacity, the quickest path problem is to find a path that sends a specific amount of data with minimum transmission time. Subject to both an assured PAR and time constraints, this paper proposes an efficient algorithm to evaluate the system reliability of an SINCN. Furthermore, a routing scheme is adopted to reinforce the system reliability. Accordingly, reliability based on the routing scheme is calculated. An application of our method on the Taiwan academic network is described to show its impact on the backup reliability for different routing schemes.     

BA-BGP:一种基于备份AS通告的域间路由协议

BGP协议通过触发全局、反应式收敛应对网络拓扑和策略变化,然而由于其收敛时间过长、收敛过程中大量AS经历不可达、环路,造成大量转发中断,难以支持VoIP、远程医疗等关键业务的应用。本文提出了一种基于备份AS通告的新型域间路由协议BA-BGP,在不影响BGP协议动态性的基础上,通过在更新报文中增加备份AS属性,使AS节点可以获取到达目标的备份AS地址,当节点面临瞬时失效时可将报文封装转发到与备份AS关联的路径,从而降低了转发中断。大量模拟实验证明,通过采用具有互联网特征的拓扑以及广泛采用的BGP策略,BA-BGP有效降低了链路失效引起的瞬时失效率与转发中断时间,增强了网络可靠性。     

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.     

采用泛播路由构建高效中继路由系统

中继路由系统由一组中继路由器组成,为不能交换路由信息的路由域提供中继路由.该系统的关键是为路由域配置恰当的中继路由器.为所有中继路由器分配一个泛播地址,将它们当作一个逻辑节点,借助泛播路由以最短路径到达该逻辑节点.此外,采用源路由的方法将数据报文路由至中继路由器.基于泛播的中继路由系统实现了中继路由的自动配置,提高了中继路由的性能和可靠性,并且与现有网络系统兼容,实施代价很小.