IP组播路由协议的研究

主要讨论了各种IP组播路由协议的工作原理,并对其性能进行了比较。     

IP组播路由算法及协议

该文主要介绍了在IP组播中使用的各种构造组播树的路由算法,以及相关的路由协议和几种新的协议。     

IPv6组播路由协议仿真研究

分析了PIMIPv6组播路由协议的原理．在NS2网络模拟环境下设计了组播网络仿真模型，编写了实现PIM组播路由协议的代码。成功模拟了协议运行过程。在此基础上。对比分析了不同PIM组播路由协议的性能特点，并指出了其应用特性。     

PIM—SM组播路由协议简析

介绍协议无关组播－松散模式（ＰＩＭ－ＳＭ）组播路由协议的关键交互过程和主要消息的格式。     

组播路由协议对网络性能的影响

组播技术对Internet发展至关重要，它以高效、可扩展的方式发送单点到多点、多点到多点数据，很多专家认为它必然成为下一代互联网的关键技术之一。现就其中组播路由协议对网络性能的影响进行了研究。     

高效率的小规模Ad Hoc组播路由协议

Ad Hoc网络中,组播路由协议具有广泛的应用前景。但由于网络拓扑的变化和节点能量的限制,设计具有高效传输能力的组播路由协议比较困难。通过综合比较表驱动路由协议与按需路由协议的优缺点,并且考虑Ad Hoc网络中节点的移动性以及路由发现与路由维护的方法对传输效率的影响,在无状态组播路由的基础上,使用表驱动与按需路由驱动相结合的路由方法,提出一种新的组播路由协议,使传输效率有较高的提升。     

移动自组网组播路由协议的分析

移动自组网是无中心、自组织、可快速展开、可移动的对等式网络,组播作为群组服务在移动自组网中应用广泛。移动自组网具有节点移动频繁、能源和带宽有限等特点,它要求组播协议能在节点频繁移动下具备良好的健壮性,传统的组播协议已不适用。文章介绍了移动自组网组播路由协议,描述了几种组播路由协议的基本运行过程,并对其性能进行了分析和比较,最后论述了组播协议在能源、安全、组播服务(QOS)、利用位置信息等方向的应用前景及面临的问题。     

链路稳定的AdHoc网络组播路由协议

Ad Hoc网络中,组播路由协议具有广泛的应用前景.但由于网络拓扑的变化,设计具有可靠数据传输能力的组播路由协议比较困难.综合考虑Ad Hoc网络中节点的移动性和节点能量对路由稳定性的影响,选取具有较高性能的链路,使得路由具有较好的稳定性.仿真结果证明,与MAODV协议相比,设计的路由协议明显提高了数据投递率,并大大降低了丢包数.     

共享路径优先组播路由算法

求解开销最小组播树在数学上归结为Steiner树问题,但由于寻找最优的Steiner树问题是NP-Complete问题,因此在组播应用中,采用启发式算法获得次优的组播树是常见的方法。该文提出了一种新的的启发式组播路由算法(Shared Path First Heuristic,SPFH)该算法在选择目的节点加入组播树时,既考虑到目的节点到树上的距离,又考虑到先加入的节点对后续加入节点的影响。算法从距离当前组播树近的目的节点中挑选节点加入组播树,选择的规则是,把能够减小其它目的节点加入组播树开销的节点先加入树。仿真结果表明,SPFH算法能找到开销接近于最优解的组播树。     

Agent-based trusted on-demand routing protocol for mobile ad-hoc networks

The routing performance in mobile ad hoc networks (MANETs) relies on the co-operation of the individual nodes that constitute the network. The existence of misbehaving nodes may paralyze the routing operation in MANETs. To overcome this behavior, the trustworthiness of the network nodes should be considered in the route selection process combined with the hop count. The trustworthiness is achieved by measuring the trust value for each node in the network. In this paper, a new protocol based on self monitoring (agent-based) and following the dynamic source routing (DSR) algorithm is presented. This protocol is called agent-based trusted dynamic source routing protocol for MANETs. The objective of this protocol is to manage trust information locally with minimal overhead in terms of extra messages and time delay. This objective is achieved through installing in each participated node in the network a multi-agent system (MAS). MAS consists of two types of agents: monitoring agent and routing agent. A new mathematical and more realistic objective model for measuring the trust value is introduced. This model is weighted by both number and size of routed packets to reflect the “selective forwarding” behavior of a node. The performance evaluation via simulation shows that our protocol is better than standard and trusted DSR. The simulation is done over a variety of environmental conditions such as number of malicious nodes, host density and movement rates.     

基于单播和无比率编码的地域性多播路由协议

车联网 VANETs(Vehicular ad hoc networks)是传统自组织网络派生的一个子类,具有鲜明的特性。传统的地域性多播协议不能有效地适用于车联网。为此,提出了基于单播和无比率编码的地域性多播路由URC-GR( unicast and rateless coding based geocast routing)协议。URC-GR协议引用两个策略解决传统地域性多播路由协议在开销和数据包传递率方面的不足。首先,利用单播机制向目标区域传输数据,然后,在目标区域内再泛洪。其次,利用无比率编码提高数据传输率。最后,将提出的URC-GR协议与IVG(Inter Vehicle Geocast)、DRG(Distributed Robust Geocast)协议进行比较,仿真结果表明URC-GR协议能够有效地降低开销和提高数据包传输率。     

QOS distributed routing protocol for mobile ad-hoc wireless networks using intelligent packet carrying systems

The wireless network should provide high throughput and positive status and this paper suggest a system that supports real-time communications with excellence of service necessities for application based on wireless communications. In addition a hybrid network that interconnects both mobile networks and wireless networks. By inheriting the features of Solid Rocket Booster technology for mobile and wireless networks the race condition, and invalid condition problem has been solved. The number of packets received may vary based on the parameter like mobility, energy, memory, bandwidth, jamming and other parameter. In past years many algorithm has been proposed for increasing the probability of packet delivery but it’s still a challenge. This paper uses an algorithm called intelligent packet carrying systems; it provides a tracking mechanism that tracks nodes in rural places. The effectives and reability has been calculated and the results are obtained using OPNET simulator.     

基于路径稳定性的MAODV路由协议的改进

在Ad Hoc网络中,节点随意快速的移动通常会造成网络拓扑结构的剧烈变化,可能导致传输链路断裂和路径的不稳定。针对这种情况,在分析现有MAODV路由改进技术的基础上,提出了一种改进的、基于路径稳定性的路由协议(RS-MAODV)。新协议与MAODV不同的地方在于:考虑构成路径的链路间的相关性,选择最稳定的路由进行数据传输,以此改善网络性能。利用NS2仿真工具对改进前后网络的丢包率及端到端延迟参数做比较,实验数据表明,改进后协议的网络丢包率及端到端延迟均得到改善。     

A QoS-aware routing mechanism for multi-channel multi-interface ad-hoc networks

To accommodate real-time multimedia application while satisfying application QoS requirements in a wireless ad-hoc network, we need QoS control mechanisms. In this paper, we propose a new routing mechanism to support real-time multimedia communication by efficiently utilize the limited wireless network capacity. Our mechanism considers a wireless ad-hoc network composed of nodes equipped with multiple network interfaces to each of which a different wireless channel can be assigned. By embedding information about channel usage in control messages of OLSRv2, each node obtains a view of topology and bandwidth information of the whole network. Based on the obtained information, a source node determines a logical path with the maximum available bandwidth to satisfy application QoS requirements. Through simulation experiments, we confirmed that our proposal effectively routed multimedia packets over a logical path avoiding congested links. As a result, the load on a network is well distributed and the network can accommodate more sessions than QOLSR. We also conducted practical experiments using wireless ad-hoc relay nodes with four network interfaces and verified the practicality of our proposal.     

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.     

时延容忍网络中基于效用转发的自适应机会路由协议

提出了一种基于效用转发的自适应机会路由算法URD,并从理论上对该算法的有效性进行了分析.通过DTN仿真软件ONE进行了具体实现和验证,并与其他的经典协议:Epidemic,PRoPHET和SprayAndWait进行了性能对比.仿真结果表明,URD算法能够增加节点相遇的可能性,提高数据分组转发的效率,减少了网络的时延开销.     

Adaptive TDMA slot assignment protocol for vehicular ad-hoc networks

This paper proposes a novel adaptive time division multiple access (TDMA) slot assignment protocol (ATSA) for vehicular ad-hoc networks. ATSA divides different sets of time slots according to vehicles moving in opposite directions. When a node accesses the networks, it choices a frame length and competes a slot based on its direction and location to communication with the other nodes. Based on the binary tree algorithm, the frame length is dynamically doubled or shortened, and the ratio of two slot sets is adjusted to decrease the probability of transmission collisions. The theoretical analysis proves ATSA protocol can reduce the time delay at least 20% than the media access control protocol for vehicular ad-hoc networks (VeMAC) and 30% than the ad-hoc. The simulation experiment shows that ATSA has a good scalability and the collisions would be reduced about 50% than VeMAC, channel utilization is significantly improved than several existing protocols.     

A secure and trust based on-demand multipath routing scheme for self-organized mobile ad-hoc networks

A mobile ad hoc network (MANET) is a self-configurable network connected by wireless links. This type of network is only suitable for provisional communication links as it is infrastructure-less and there is no centralized control. Providing QoS and security aware routing is a challenging task in this type of network due to dynamic topology and limited resources. The main purpose of secure and trust based on-demand multipath routing is to find trust based secure route from source to destination which will satisfy two or more end to end QoS constraints. In this paper, the standard ad hoc on-demand multi-path distance vector protocol is extended as the base routing protocol to evaluate this model. The proposed mesh based multipath routing scheme to discover all possible secure paths using secure adjacent position trust verification protocol and better link optimal path find by the Dolphin Echolocation Algorithm for efficient communication in MANET. The performance analysis and numerical results show that our proposed routing protocol produces better packet delivery ratio, reduced packet delay, reduced overheads and provide security against vulnerabilities and attacks.     

Octopus: A fault-tolerant and efficient ad-hoc routing protocol

Mobile ad-hoc networks (MANETs) are failure-prone environments; it is common for mobile wireless nodes to intermittently disconnect from the network, e.g., due to signal blockage. This paper focuses on withstanding such failures in large MANETs: we present Octopus, a fault-tolerant and efficient position-based routing protocol. Fault-tolerance is achieved by employing redundancy, i.e., storing the location of each node at many other nodes, and by keeping frequently refreshed soft state. At the same time, Octopus achieves a low location update overhead by employing a novel aggregation technique, whereby a single packet updates the location of many nodes at many other nodes. Octopus is highly scalable: for a fixed node density, the number of location update packets sent does not grow with the network size. And when the density increases, the overhead drops. Thorough empirical evaluation using the ns2 simulator with up to 675 mobile nodes shows that Octopus achieves excellent fault-tolerance at a modest overhead: when all nodes intermittently disconnect and reconnect, Octopus achieves the same high reliability as when all nodes are constantly up. A preliminary version of this paper appears in Proceedings of the 24th IEEE Symposium on Reliable Distributed Systems (SRDS 2005) October 26–28, 2005, Orlando, Florida. Idit Keidar is a faculty member at the department of Electrical Engineering at the Technion Israel Institute of Technology, and a recipient of the national Alon Fellowship for new faculty members. She holds Ph.D., M.Sc. (summa cum laude), and B.Sc (summa cum laude) degrees from the Hebrew University of Jerusalem. She was a postdoctoral research associate at MIT’s laboratory for Computer Science, where she held post-doctoral fellowships from Rothschild Yad-Hanadiv and NSF CISE. Dr. Keidar has consulted for BBN Technologies (a Verizon Company) in the area of fault-tolerance and intrusion tolerance, and for Microsoft Research in the area of fault-tolerant storage systems. Dr. Keidar’s research focuses on reliability in distributed algorithms and system. She is the academic head of Software Systems Laboratory at the Technion. Dr. Keidar served as a member of the Steering Committee of the ACM Symposium on Principles of Distributed Computing (PODC), has served on numerous program committees of leading conferences in the area of distributed and parallel computing, has twice served as a vice-chair for the IEEE International Conference on Distributed Computing Systems (ICDCS), and once served as a vice-chair for Euro-Par. Yoav Barel is a Senior Business Line Manager at Sun Microsystems. He holds a B.Sc from the Technion—Israel Institute of Technology. Mr. Barel works with wireless carriers world wide and assists them in deploying innovative services based on cutting edge Java technologies. Roie Melamed is a research staff member at IBM Haifa Research Laboratory. He holds Ph.D. and B.A. (cum laude) degrees from the Technion—Israel Institute of Technology. Dr. Melamed’s research focuses on reliability in distributed systems.