Data Integration Strategy for Database Grids Based on P2P Framework

The differences between the data integration of a dynamic database grid （DBG） and that of a distributed database system are analyzed, and three kinds of data integration strategies are given on the background of DBG based on Peer to Peer （P2P） framework, including the centralized data integration （CDI） strategy, the distributed data integration （DDI） strategy and the filter-based data integration （FDDI） strategy. CDI calls all the database grid services （DGSs） at a single node, DDI disperses the DGSs to multiple nodes, while FDDI schedules the data integration nodes based on filtering the keywords returned from DGSs. The performance of these three integration strategies are compared with and analyzed by simulation experiments. FDDI is more evident for filtering the keywords with data redundancy increasing. Through the reduction of large amount of data transportation, it effectively shortens the executing time for the task and improves its efficiency.

Adaptive Trust Management Framework in P2P Grid Computing

In P2P Grid computing systems, the authorization decision is often tackled by two different trust management methods： policy-based approach, where authorization are built on logical rules and verifiable properties encoded in signed credentials, and reputation-based approach, based on collecting, aggregating and disseminating reputation among the peers. However, the overhead caused by proof of compliance on authorization and the absence of certifying authorities may negate the strong and objective security advantages of policy-based approach, whilst vagueness, complexity and inaccurate characterization caused by reputation evolution may eliminate the quantitative and flexible advantages of reputation-based approach. We propose an adaptive trust management framework, which combines the merit of policy proof and reputation evolution such that authorization is aware of not only the strong and objective security traits, but also the calculability and the availability security traits. Finally, the framework of system is proposed.

Task scheduling scheme by checkpoint sharing and task duplication in P2P-based desktop grids

A scheduling scheme is proposed to reduce execution time by means of both checkpoint sharing and task duplication under a peer-to-peer(P2P) architecture. In the scheme, the checkpoint executed by each peer(i.e., a resource) is used as an intermediate result and executed in other peers via its duplication and transmission. As the checkpoint is close to a final result, the reduction of execution time for each task becomes higher, leading to reducing turnaround time. To evaluate the performance of our scheduling scheme in terms of transmission cost and execution time, an analytical model with an embedded Markov chain is presented. We also conduct simulations with a failure rate of tasks and compare the performance of our scheduling scheme with that of the existing scheme based on client-server architecture. Performance results show that our scheduling scheme is superior to the existing scheme with respect to the reduction of execution time and turnaround time.

How signaling and search costs affect information asymmetry in P2P lending:the economics of big data

In the past decade,online Peer-to-Peer(P2P)lending platforms have transformed the lending industry,which has been historically dominated by commercial banks.Information technology breakthroughs such as big data-based financial technologies(Fintech)have been identified as important disruptive driving forces for this paradigm shift.In this paper,we take an information economics perspective to investigate how big data affects the transformation of the lending industry.By identifying how signaling and search costs are reduced by big data analytics for credit risk management of P2P lending,we discuss how information asymmetry is reduced in the big data era.Rooted in the lending business,we propose a theory on the economics of big data and outline a number of research opportunities and challenging issues.

How the Information and Communications Technology Threaten Our Privacy： The Case of Email and P2P Propagation Models

With the rapid growth of information and communication technology （ICT）, the violation of information privacy has increased in recent years. The privacy concerns now re-emerge right because people perceives a threat from new ICT that are equipped with enhanced capabilities for surveillance, storage, retrieval, and diffusion of personal information. With the trend in the prevalence and the easy use of ICT, it is of necessary to pay much attention to the issue how the ICT can threaten the privacy of individuals on the Internet. While the Email and P2P （Peer-to-Peer） tools are the most popular ICT, this paper aims at understanding their respectively dissemination patterns in spreading of personal private information. To this purpose, this paper using dynamic model technique to simulate the pattern of sensitive or personal private information propagating situation. In this study, an Email propagation model and a Susceptible-lnfected-Removed （SIR） model are proposed to simulate the propagation patterns of Email and P2P network respectively. Knowing their dissemination patterns would be helpful for system designers, ICT manager, corporate IT personnel, educators, policy makers, and legislators to incorporate consciousness of social and ethical information issues into the protection of information privacy.

PeerMD:A P2P Molecular Dynamics Simulation Framework Based on Web Services

PeerMD, a P2P molecular dynamics simulation frame-work based on Web services is proposed. It utilizes rich free CPU time and network bandwidth of P2P networks to provide enough resources for dynamics simulation of bio-macromolecule, and has resolved the problem that it is difficult to interoperate between heterogeneous peers in P2P environment through Web services. Structure of PeerMD is given. Function, input and output of molecular dynamics simulation Web service are defined. Processes of publishing, discovering and invoking of molecular dynamics simulation Web service based on multi-level SuperPeer are given. A protocol system of PeerMD is implemented on a basic P2P platform JXTA, and experimental simulations of tumor necrosis fact alpha （TNF-α） and two mutations of it are executed on the protocol system. Simulation results show that PeerMD can speed up molecular dynamics simulation perfectly.

Greedysearch based service location in P2P networks

A model is built to analyze the performance of service location based on greedy search in P2P networks. Hops and relative QoS index of the node found in a service location process are used to evaluate the performance as well as the probability of locating the top 5% nodes with highest QoS level. Both model and simulation results show that, the performance of greedy search based service location improves significantly with the increase of the average degree of the network. It is found that, if changes of both overlay topology and QoS level of nodes can be ignored during a location process, greedy-search based service location has high probability of finding the nodes with relatively high QoS in small number of hops in a big overlay network. Model extension under arbitrary network degree distribution is also studied.

An ALM Model for Streaming Media Service in P2P-SIP Network

Application layer multicast （ALM） has been widely applied in Internet, as a substitute for IP multicast. However, it causes network load to increase because it adopts unlcast in data transmission, which limits the application. In this article, in order to improve the ALM performance in P2P-SIP network, an ALM model was proposed which reduced network load via merging messages in concast mode. Finally network simulations prove that this model has better benefit on single node load and average network load. Therefore, it is suitable for streaming media service in P2P-SIP Network.

AR Display Method of a Person＇s Identifier near the Head on a Camera Screen Based on the GPS Information and Face Detection Using Ad hoc and P2P Networking

The spread of social media has increased contacts of members of communities on the lntemet. Members of these communities often use account names instead of real names. When they meet in the real world, they will find it useful to have a tool that enables them to associate the faces in fiont of them with the account names they know. This paper proposes a method that enables a person to identify the account name of the person （＂target＂） in front of him/her using a smartphone. The attendees to a meeting exchange their identifiers （i.e., the account name） and GPS information using smartphones. When the user points his/her smartphone towards a target, the target＇s identifier is displayed near the target＇s head on the camera screen using AR （augmented reality）. The position where the identifier is displayed is calculated from the differences in longitude and latitude between the user and the target and the azimuth direction of the target from the user. The target is identified based on this information, the face detection coordinates, and the distance between the two. The proposed method has been implemented using Android terminals, and identification accuracy has been examined through experiments.

Detecting P2P Botnet by Analyzing Macroscopic Characteristics with Fractal and Information Fusion

Towards the problems of existing detection methods,a novel real-time detection method(DMFIF) based on fractal and information fusion is proposed.It focuses on the intrinsic macroscopic characteristics of network,which reflect not the "unique" abnormalities of P2P botnets but the "common" abnormalities of them.It regards network traffic as the signal,and synthetically considers the macroscopic characteristics of network under different time scales with the fractal theory,including the self-similarity and the local singularity,which don't vary with the topology structures,the protocols and the attack types of P2P botnet.At first detect traffic abnormalities of the above characteristics with the nonparametric CUSUM algorithm,and achieve the final result by fusing the above detection results with the Dempster-Shafer evidence theory.Moreover,the side effect on detecting P2P botnet which web applications generated is considered.The experiments show that DMFIF can detect P2P botnet with a higher degree of precision.

Cluster based hierarchical resource searching model in P2P network

For the problem of large network load generated by the Gnutella resource-searching model in Peer to Peer （P2P） network, a improved model to decrease the network expense is proposed, which establishes a duster in P2P network, auto-organizes logical layers, and applies a hybrid mechanism of directional searching and flooding. The performance analysis and simulation results show that the proposed hierarchical searching model has availably reduced the generated message load and that its searching-response time performance is as fairly good as that of the Gnutella model.

A Model of Mobile P2P Network Architecture based on Agent

A model of mobile peer to peer (P2P) network architecture based on agent for mobile value-added services is proposed in this paper. By using this model, wireless devices can build a P2P network dynamically, and then they can access and transmit information peer to peer. An ontologybased semantic information description method is also proposed for the mobile wireless devices. The merit of this method is to enhance search efficiency. Moreover, a small system, called CellChat, has been implemented based on this model in the lab environment. Experimental results are provided to show that the benefi ts of the proposed method. This method will become an effective solution for mobile value-added services in 3G network.

Improving Resilience against DDoS Attack in Unstructured P2P Networks

In unstructured peer-to-peer （P2P） systems such as Gnutella, a general routing search algorithm is used to blindly flood a query through network among peers. But unfortunately, malicious nodes could easily make use of the search approach launching distributed denial of service （DDoS） attack which aims at the whole network. In order to alleviate or minimize the bad effect due to behavior of malicious nodes using the flooding search mechanism, the paper proposes a Markov-based evaluation model which exerts the trust and reputation mechanism to computing the level of trustworthy of nodes having the information requested by evaluation of the nodes＇ history behavior. Moreover, it can differentiate malicious nodes as early as possible for isolating and controlling the ones＇ message transmitted. The simulation results of the algorithm proposed show that it could effectively isolate malicious nodes, and hold back the transmission of vicious messages so that it could enhance tolerance of DDoS based on flooding in Guutella-like P2P network.

A Chord-based resource scheduling approach in drug discovery grid

This paper presents a resource scheduling approach in grid computing environment. Using P2P technology, this novel approach can schedule dynamic grid computing resources efficiently. Grid computing resources in different domains are organized into a structured P2P overlay network. Available resource information is published in type of grid services. Task requests for computational resources are also presented as grid services. Problem of resources scheduling is translated into services discovery. Different from central scheduling approaches that collect available resources information, this Chord-based approach forwards task requests in the overlay network and discovers satisfied resources for these tasks. Using this approach, the computational resources of a grid system can be scheduled dynamically according to the real- time workload on each peer. Furthermore, the application of this approach is introduced into DDG, a grid system for drug discovery and design, to evaluate the performance. Experimental results show that computational resources of a grid system can be managed efficiently, and the system can hold a perfect load balance state and robustness.

A Review of P2P Financial Research

Since 2007,people's spending habits began to change:from cash to the bank card,from mobile phone to non-cash transactions,from traditional finance to network finance.And the rapid rise of emerging industries results in many of the P2P Financial Corporation established,it makes the P2P platform trading volume continue to rise at an alarming rate.In this context,the industry self-discipline environment is like the mining of good and evil.The atmosphere was foul,bad phenomenon,investors difficult activist phenomenon,the phenomenon of credit default as one falls,another rises to a series of problems,such as serious absence of P2P financial supervision to promote the healthy and sustainable development,is a major problem for all participants,which must to be solved.Firstly,P2P development of management mode in the current situation in our country is discussed,and then it analyzes the P2P network of financial management platform,finally it proposes the existing problems in the relative countermeasures and suggestions of effective P2P financing mode,hoping to promote its advantages,overcoming the disadvantages of P2P.

基于P-Grid的P2P信息共享系统的设计和实现

文中分析了现有P2P系统存在问题,深入研究了P Grid系统构建和信息搜索两方面技 术,设计实现了基于P Grid技术的完全对等的信息共享系统SharePeer。系统通过局域网运行测试, 分析表明SharePeer能在比较不稳定的环境中运行,并且具有较高的搜索效率。

Grid和P2P混合环境中一种基于信任的资源搜索机制

Grid和P2P两种分布式计算模式中的资源搜索算法均假设节点提供可靠的资源,但Grid和P2P混合计算环境的动态、异构、自组织等特点使得一些节点存在冒名和提供虚假服务等行为。本文对基于经验和最好邻居搜索机制进行改进,引入信任因子,提出了基于信任的资源搜索机制。该机制有效抑制了欺骗行为,提高了资源搜索的可靠性和安全性。

基于P2P和Web Service的数字图书馆资源共享框架研究

针对现有数字图书馆框架体系存在的服务器易单点失效、负载不均衡、资源共享困难、异构信息仓储的互操作等问题,本文在较系统地分析P2P技术和Web Service技术的基础上,设计出一个基于P2P和Web Service技术的数字图书馆资源共享框架,并对组成该框架的三层结构——P2P层、资源节点层、应用服务层予以详尽的阐述。

P2P／Web Service与网格资源发现服务研究

资源发现是网格计算技术一个重要的研究领域。本文根据经典的五层沙漏网格架构模型,结合P2P、Web Service技术,提出了一个网格资源发现模型。使用P2P网络计算模式,充分利用网络边缘的终端设备发现共享资源,可以大大提高发现速度,降低服务器的负载。同时,使用了Web Service来发布网格结点提供的服务。本文中提出了该模型使用的通讯协议簇、模型的实现方法。本文具体的底层发现服务使用perl实现;使用Frontier-RPC发布服务和访问均已经实现。

基于P2P网络的Web Services发现机制

提出一种改进的两层混合式P2P网络模型,用该模型作为Web Services发现技术的底层网络.该网络模型主要在两方面进行改进:在网络结构方面提出CP节点分类策略和SP节点分组策略;在网络组织方面提出一种基于Web Services兴趣因子空间的节点分布自调整策略.