基于Super-peer的P2P流媒体服务系统构架的研究

在分析比对现有P2P流媒体服务系统构架的基础上,提出了一种新的P2P流媒体服务系统构架,在构架中引入了带有冗余的Super-peer结构,使得该流媒体服务系统可以达到较高的效率和健壮性。

基于Super Peer的P2P e-Learning模型

在分析各种P2P网络特点的基础上,提出了分布式环境中基于超节点的P2P e-Learning模型。对特定peer组中超节点的加入和超节点的服务进行了具体描述。针对e-Learning的特性,给出了模型中的数据抽象和本体描述,并对该P2P网络模型在文件传输方面的性能做了分析。

P2P网络Peer访问Web Service的研究和实现

文章首先简要介绍了P2P网络和WebService的技术背景,接着提出了P2P网络与WebService集成的思想,为此提出WebServiceBroker的概念,从而实现P2P网络Peer透明访问WebService。

一种基于Super Peer结构的P2P视频点播系统的设计与实现

分析各种P2P网络的特点,为了使用户在视频点播过程中获得快速、稳定的流媒体数据,提出了一种采用Super Peer结构的P2P视频点播设计方案。讨论了以该方案为基础的拓扑树的构建、拓扑树的变更等关键技术,并对该系统进行了性能分析,证明其具有较好的可靠性和稳定性。

Peer selecting model based on FCM for wireless distributed P2P files sharing systems

IIn order to improve the performance of wireless distributed peer-to-peer(P2P)files sharing systems,a general system architecture and a novel peer selecting model based on fuzzy cognitive maps(FCM)are proposed in this paper.The new model provides an effective approach on choosing an optimal peer from several resource discovering results for the best file transfer.Compared with the traditional min-hops scheme that uses hops as the only selecting criterion,the proposed model uses FCM to investigate the complex relationships among various relative factors in wireless environments and gives an overall evaluation score on the candidate.It also has strong scalability for being independent of specified P2P resource discovering protocols.Furthermore,a complete implementation is explained in concrete modules.The simulation results show that the proposed model is effective and feasible compared with min-hops scheme,with the success transfer rate increased by at least 20% and transfer time improved as high as 34%.

SSABC:a super-peer selection algorithm based on capacity

Combining the characteristics of peer-to-peer （P2P） and grid, a super-peer selection algorithm--SSABC is presented in the distributed network merging P2P and grid. The algorithm computes nodes capacities using their resource properties provided by a grid monitoring and discovery system, such as available bandwidth, free CPU and idle memory, as well as the number of current connections and online time. when a new node joins the network and the super-peers are all saturated, it should select a new super-peer from the new node or joined nodes with the highest capacity. By theoretical analyses and simulation experiments, it is shown that super-peers selected by capacity can achieve higher query success rates and shorten the average hop count when compared with super-peers selected randomly, and they can also balance the network load when all super-peers are saturated. When the number of total nodes changes, the conclusion is still valid, which explains that the algorithm SSABC is feasible and stable.

Super-peer网络中基于信誉的资源发现算法

在Super-peer网络模型下,提出一种基于信誉的资源发现算法,通过计算域内和域间节点的信誉度,将请求信息转发给信誉高的节点,在保证资源发现效率的同时提高资源查找的可靠性。

基于Super-Peer架构的信息查询算法研究

本文介绍了传统P2P的基本结构,比较了其优点和不足,阐述了移动Agent的基本特性。在Super-Peer架构的P2P网络模型基础上提出了一种基于移动Agent的信息查询算法,并利用时延阀值控制整个算法,从而提高了查询效率。

Analytical Comparison of Resource Search Algorithms in Non-DHT Mobile Peer-to-Peer Networks

One of the key challenges in ad-hoc networks is the resource discovery problem.How efciently&quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying question?Broadcasting is a basic technique in the Mobile Ad-hoc Networks(MANETs),and it refers to sending a packet from one node to every other node within the transmission range.Flooding is a type of broadcast where the received packet is retransmitted once by every node.The naive ooding technique oods the network with query messages,while the random walk scheme operates by contacting subsets of each node’s neighbors at every step,thereby restricting the search space.Many earlier works have mainly focused on the simulation-based analysis of ooding technique,and its variants,in a wired network scenario.Although,there have been some empirical studies in peer-to-peer(P2P)networks,the analytical results are still lacking,especially in the context of mobile P2P networks.In this article,we mathematically model different widely used existing search techniques,and compare with the proposed improved random walk method,a simple lightweight approach suitable for the non-DHT architecture.We provide analytical expressions to measure the performance of the different ooding-based search techniques,and our proposed technique.We analytically derive 3 relevant key performance measures,i.e.,the avg.number of steps needed to nd a resource,the probability of locating a resource,and the avg.number of messages generated during the entire search process.

Research and Development of P2P Worms

With the development and the application of many popular peer-to-peer （P2P） systems such as eMule and BitTorrent, worms probably employ the features of these P2P networks to put them at risk. Some features, such as the local routing table and the application routing mechanism, are helpful to quickly distribute the P2P worms into the networks. This paper aims to give a comprehensive survey of P2P worms. The definition and the classification of P2P worms are discussed firstly. Then, the research and development of P2P worms, including experimental analysis, propagation modeling, and defensive approaches, are addressed and analyzed in detail.

A Potential Approach of Internet Worm Propagation Based on P2P

Various kinds of active worms have been plunging into the network flows, which make the Internet security problem more serious. Our research on a potential propagation approach of active worms, P2P-based propagation approach, is given in this paper. To measure the propagating performance of our approach, the SEI （Susceptible-Exposed-Infected） propagation model is presented. It proves that with the idea of pure P2P architecture, worms can be hidden in the early stage of propagation, and then infect most of the hosts in a shorter period. By comparing our SEI propagation model with the Simple Epidemic Model, we observe that the size of a worm is a significant parameter which can affect the propagating performance. When the size of the worm becomes large, our approach can still show an excellent propagating performance.

Epidemiological modeling of passive worm propagation on the P2P file-sharing network

The peer-to-peer（P2P） file-sharing network as a vehicle of disseminating files has become very popular. The appearance of dozens of kinds of passive worms on this network has, however, made it unsecured. This problem has been paid attention and a few of models for passive worm propagation has been presented. Unfortunately, the dynamic properties of this network are ignored in these models. Given the fact, the characteristics of both this network and the passive worm are identified, and on this basis a new mathematical model of passive worm propagation on the P2P network is presented in applying epidemiology in this paper. Note that the dynamic properties of this network are considered in the presented model. The model has been validated by large scale simulation experiments, which demonstrates that the presented model may be used for analyzing the behaviors of passive worms and predicting the trend of their propagation.

Modeling active worm propagation on the P2P network

This paper analyzes the characteristics of the Peer-to-Peer （P2P） active worm and its attacking mechanism, and then proposes a mathematical model of propagation of the P2P active worm applying Epidemiology. Based on the analysis on the protocols of realistic P2P systems, a software which can be used to simulate the P2P network environment and the propagation of P2P active worm is imple- mented in this paper. A large number of simulation experiments are performed using the developed simulation software. The results from these simulation experiments validate the proposed model, which means that the model can be used to analyze the spreading behaviors of the P2P active worm and predict its trend.

Neighbour Peer Selection Scheme Based on Effective Capacity for Mobile Peer-to-Peer Streaming

For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This paper proposes a novel Effective Capacity Peer Selection (ECPS) scheme based on effective capacity. In the ECPS scheme, the neighbour peer selection problem was modeled using the Multiple Attribute Decision Making (MADM) theory, which considered multiple factors of candidate peers, including Signal to Interference and Noise Ratio (SINR), residency time, power level, security, moving speed, and effective capacity. This model could increase the suitability of ECPS for wireless mobile environments. Then, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to solve the MADM problem and identify the preferred neighbour peers. Simulation results show that the ECPS scheme can improve the network throughput, reduce packet delay by about 82%, and almost double the packet delivery ratio of the mobile P2P streaming service.

基于P2P技术的流媒体服务模型研究

探讨了现有的流媒体集中式(客户机-服务器-客户机)服务模型,及现阶段基于该方式的各种改进服务方式:内容传播网络、集群服务器、组播技术。研究了基于P2P技术的流媒体混和式服务模型,并在Windows操作系统下用Java2语言对该模型客户端进行实现,并且指出该模型的优点和不足之处。

P2P与Grid的结合:P2P-Grid模型研究

分析P2P和网格技术各自的特点,对超级Peer内部的资源模型进行了讨论,提出了全局P2P-Grid网格资源组织模型。

FALPS：大规模P2P系统网络仿真平台

随着P2P技术的发展,传统的网络仿真平台已经不能满足研究需要。如何设计支持大规模P2P内容分发仿真的平台是亟待解决的问题。通过建立BackboneNet模型,并采取了"事件"合并、非尾片段丢弃"、事件队列"大小控制三个关键算法设计了一种用于大规模P2P内容分发系统的包级离散事件驱动网络仿真平台FALPS。该平台具有内存消耗低、速度快、精确度高的特点,可用于仿真具有105数量级节点规模的P2P系统。

一种支持多维资源描述的高效P2P路由算法

在分析现有P2P(peer to peer)路由算法的基础上,提出了一种基于二阶矩定位、支持多维资源数据描述的高效资源路由算法——FAN(flabellate addressable network)路由算法.FAN算法将节点映射到统一的多维笛卡尔空间,并以节点相对空间原点的二阶矩作为子空间管理和资源搜索的依据.FAN路由算法具有O(log(N/k))的高路由效率,在节点加入和退出FAN网络时,更新路由信息的代价为O(klog(N/k)).实验结果表明,FAN路由算法具有路由效率高、维护代价小的优点,是一种P2P环境中支持多维资源数据描述的高效结构化资源路由算法.而且,目前部分基于CAN(content-addressable network)网络的改进算法也可以在FAN网络中适用,并获得更好的路由效率和更低的维护代价.

P2P技术的发展与前瞻

本文介绍了P2P技术的背景与发展现状 ,对P2P技术的应用前景提出一些前瞻性的看法。

P2P环境下影像数据流传输的资源定位及选择研究

在传统P2P资源定位方法的基础上,对空间P2P系统采用一种网格索引peer分组来实现资源定位,并探讨peer选择策略来优化资源定位结果,采用历史速度记录反馈推测peer选择优先级使得性能高和可靠的peer可以优先被选择。大量模拟实验测试peer选择策略局部最优和不等概率随机选择两种模式,结果显示peer选择策略的有效性以及有效性程度取决于peer个数、资源文件大小和用户行为等应用场景。