Dissertations / Theses on the topic 'Peer to peer architecture'
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Liu, Nianwang, and 刘年旺. "Request peer selection for peer-to-peer streaming." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206752.
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As the Internet develops and technology evolves, multimedia traffic dominates the Internet. Traditional client-server based video streaming solutions are expensive and suffering from the scalability issue. Inspired by the immense success and efficiency of BitTorrent in distributing file contents to large groups of users, the peer-to-peer (P2P) paradigm has been adopted to provide streaming services including both P2P video-on-demand (VoD) and P2P live streaming.
Among the design challenges, one open yet fundamental question is, how to identify the most suitable neighbor for a peer to make a piece request. We refer this problem as the request peer selection problem. Properly allocating the piece request to potential providers is essential to the system and would help to balance the load at each peer. A well designed request peer selection algorithm increases the requestor’s probability to download the desired piece timely which leads to enhanced video quality and improved playback continuity. This thesis aims to enhance the overall system performance by proposing optimized request peer selection algorithms for both P2P VoD and P2P live streaming systems.
In P2P VoD, participating peers start playback from the very beginning of a stored video. The playback-points of peers, as well as the amount of video contents/pieces the peers cached, depend on when they join the video session, or their viewing ages. The content buffered by younger peers is a subset of older peers, thus collaborative piece exchange among peers is undermined due to the unbalanced supply and demand. To address this issue, a playback-point based request peer selection algorithm: closest playback-point first (CPF) is proposed. Specifically, when a peer requests a particular video piece, among the set of potential providers, a request is sent to the peer that has the smallest playback-point difference with itself. With CPF, peers with similar content availability are loosely grouped into clusters to maximize the utilization of individual peer’s upload capacity. Extensive packet level simulations show that with CPF, the video playback quality is enhanced and the VoD server load is significantly reduced.
Unlike P2P VoD, P2P live streaming systems have to meet real-time playback constraints, which makes it even more challenging. To better regulate the network traffic and to balance the load among peers, a service response time (SRT) based request peer selection algorithm is proposed. In particular, a peer in the network estimates the service response time (SRT) between itself and each neighboring peer. SRT is measured from when a data piece request is sent until the requested piece arrives. When a peer makes a piece request, the neighbor with smaller SRT and fewer data pieces would be favored. The rationale is: smaller SRT implies excess serving capacity and fewer data pieces suggests fewer potential piece requests received. Extensive packet level simulations show that the traffic load in the network is better balanced, the streaming server load is reduced, and the overall quality of service, measured by playback continuity, startup delay etc., is improved.published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy
2
Gerke, Jan. "A generic Peer-to-Peer architecture for internet services /." Zürich : TIK Institut für Technische Informatik und Kommunikationsnetze, ETH Zürich, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16673.
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Tang, Jia. "An agent-based peer-to-peer grid computing architecture." Access electronically, 2005. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060508.151716/index.html.
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Ou, Z. (Zhonghong). "Structured peer-to-peer networks:hierarchical architecture and performance evaluation." Doctoral thesis, University of Oulu, 2010. http://urn.fi/urn:isbn:9789514262487.
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Abstract
Peer-to-Peer (P2P) networking changes the way of people utilizing Internet, for example, sharing and consuming digital content, from the ground up. It continues to show its power and strength when it is combined with other emerging technologies, such as Web Services. This thesis contributes to the research and development of P2P networks from four aspects.
Firstly, a P2P and Web Services converged multiple-tier system architecture is proposed. The architecture proposed enables providing Web Services in the context of heterogeneous access networks in an efficient way by utilizing P2P paradigm. A lightweight middleware architecture is introduced to fit the diversified mobile terminals. A theoretical analysis is given to provide a comparative study with the conventional centralized architecture.
Secondly, a General Truncated Pyramid Peer-to-Peer (GTPP) architecture is presented to analyze the performance of hierarchical architecture compared with flat architecture. The motivation behind the GTPP architecture is to see whether an added tier can bring with it added value and functionality. A detailed mathematical analysis is provided which takes into consideration various performance metrics, including the lookup hopcount, lookup latency, maintenance traffic from a single peer point of view, and maintenance traffic from the whole system point of view. Furthermore, simulation results with respect to the lookup hopcount are also provided. Through mathematical analysis and simulation results, an optimal value regarding the number of tiers of the GTPP architecture is found, showing that 2~3 tiers are appropriate for most of situations. A specialized model is also proposed to improve the performance of hierarchical architecture.
Thirdly, the performance evaluation of a communication-oriented Kademlia-based P2P system is provided in detail. NetHawk EAST-based simulation models and a prototype are both utilized to evaluate the performance. Simulation results from NetHawk EAST-based simulation models demonstrate the optimal design choices regarding the resource lookup parallelism degree and resource replication degree, and show the unnecessary existence of the messages used to detect the liveness of peers in a DHT overlay. Measurements from the prototype show the feasibility of mobile nodes acting as fully fledged overlay nodes from three different perspectives, namely CPU processing load, network traffic load, and battery consumption. The optimal size of packets which consumes battery in the most efficient way is also found through battery consumption measurements.
Fourthly, the effects of different churn models on the performance of structured P2P networks are analyzed. Specifically, three typical churn models are analyzed to provide a comparative result. The simulation results show that the difference among the effects of different churn models on the performance of structured P2P networks is quantitative rather than qualitative. This provides some guidance for the selection of different churn models for the contemporary researchers.
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Ieong, Sze-chung Ricci, and 楊思聰. "Analysis of peer-to-peer investigation model." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50662247.
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Peer-to-Peer (P2P) file sharing is one of the most commonly used methods for sharing files over a network, especially large files such as videos or music recordings. In North America, P2P file-sharing networks occupied approximately 50% of the network traffic in 2011 [3]. Many files shared through P2P networks are related to Internet piracy or unintentional file sharing. Foxy P2P network, a typical search-based P2P network, is in the spotlight for sensitive file sharing. Peers download the files by using keywords instead of resource links. Therefore, the investigation mechanisms developed to identify the first seeder in Bit-Torrent network – another type of P2P network [54], cannot be applied to this scenario.
Identifying the first seeder is the critical step in P2P investigation. The investigator cannot collect necessary evidence without locating the first seeder. Therefore, conducting forensic analysis is impossible. Moreover, validating the actual first seeder will be challenging when more than one uploader is identified.
This study started by analyzing different P2P networks and comparing their underlying features. Categorizing the P2P file-sharing networks resulted in the identification of the key functions for file sharing. Two difficulties in Foxy network investigation, namely, unknown file publication time and uncertainty of network coverage by uploaders and downloaders, were also highlighted.
To further examine the Foxy P2P network, a controlled testing environment for the P2P network was developed in a network simulation environment (i.e., NS-3). Tests were conducted in the simulation environment, and the effects of various attributes (file size, file transfer rate, file popularity) on the growth of the number of uploaders (represented by the seeder curve) were analyzed.
Results demonstrated that the shape of the seeder curve was affected by the file propagation feature of the file-sharing activity. The slow-rising period, which represented the competition for the file content being shared among peers, was recorded at the initial stage of file sharing in the P2P network. Competition for file content is one of the key factors related to the success or failure in performing P2P investigation through the simulation environment.
An investigation algorithm and four validation rules were proposed based on the above key factor to perform P2P investigation. Through controlled and randomly selected experiments, the investigation could be applied to the search-based P2P file-sharing environment as long as the required slow-rising period in other P2P networks was followed [68].
Analysis of the experimental results demonstrated the ability of the proposed investigation model and the validation rules. The results verified and confirmed the observed seeder in the P2P file-sharing scenario if competitions among downloaders for the shared file content existed. The limitations of the P2P investigation and validation model were also discussed.published_or_final_version
Computer Science
Doctoral
Doctor of Philosophy
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Jayanthi, Praveena. "Scalable Proxy Architecture for Mobile and Peer-to-Peer Networks." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/cs_theses/34.
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The growth of wireless telecommunications has stipulated the interest for anywhere-anytime computing. The synergy between networking and mobility will engender new collaborative applications with mobile devices on heterogeneous platforms. One such middleware is “SYSTEM ON MOBILE DEVICES”, SYD developed by the Yamacraw Embedded Systems research team. This type of middleware is an opening step towards Peer-to-Peer mobile networks. This project envisioned collaborative applications among mobile devices and PDAs were used as servers. This thesis studies various existing architectures in mobile computing and their scalability issues. We also proposed new scalable flexible thick client proxy system FTCPS, an architecture suitable for mobile Peer-to-Peer networks. Our empirical study showed that FTCPS has low response time compared to other architectures.
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Klampanos, Iraklis Angelos. "A cluster-based architecture for peer-to-peer information retrieval." Thesis, University of Glasgow, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433270.
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Veiga, Hélder Manuel Lima. "Distributed traffic measurement system with a peer-to-peer architecture." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1916.
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Mestrado em Engenharia ElectrónicaAs características do tráfego na Internet são cada vez mais complexas devido à crescente diversidade de aplicações, à existência de diferenças drásticas no comportamento de utilizadores, à mobilidade de utilizadores e equipamentos, à complexidade dos mecanismos de geração e controlo de tráfego, e à crescente diversidade dos tipos de acesso e respectivas capacidades. Neste cenário é inevitável que a gestão da rede seja cada vez mais baseada em medições de tráfego em tempo real. Devido à elevada quantidade de informação que é necessário processar e armazenar, é também cada vez maior a necessidade das plataformas de medição de tráfego assumirem uma arquitectura distribuída, permitindo o armazenamento distribuído, replicação e pesquisa dos dados medidos de forma eficiente, possivelmente imitando o paradigma Peer-to-Peer (P2P). Esta dissertação descreve a especificação, implementação e teste de um sistema de medição de tráfego com uma arquitectura distribuída do tipo P2P, que fornece aos gestores de rede uma ferramenta para configurar remotamente sistemas de monitorização instalados em diversos pontos da rede para a realização de medições de tráfego. O sistema pode também ser usado em redes orientadas à comunidade onde os utilizadores podem partilhar recursos das suas máquinas para permitir que outros realizem medições e partilhem os dados obtidos. O sistema é baseado numa rede de overlay com uma estrutura hierárquica organizada em áreas de medição. A rede de overlay é composta por dois tipos de nós, denominados de probes e super-probes, que realizam as medições e armazenam os resultados das mesmas. As superprobes têm ainda a função de garantir a ligação entre áreas de medição e gerir a troca de mensagens entre a rede e as probes a elas conectadas. A topologia da rede de overlay pode mudar dinamicamente, com a inserção de novos nós e a remoção de outros, e com a promoção de probes a super-probes e viceversa, em resposta a alterações dos recursos disponíveis. Os nós armazenam dois tipos de resultados de medições: Light Data Files (LDFs) e Heavy Data Files (HDFs). Os LDFs guardam informação relativa ao atraso médio de ida-evolta de cada super-probe para todos os elementos a ela ligados e são replicados em todas as super-probes, fornecendo uma visão simples mas facilmente acessível do estado da rede. Os HDFs guardam os resultados detalhados das medições efectuadas a nível do pacote ou do fluxo e podem ser replicados em alguns nós da rede. As réplicas são distribuídas pela rede tendo em consideração os recursos disponíveis nos nós, de forma a garantir resistência a falhas. Os utilizadores podem configurar medições e pesquisar os resultados através do elemento denominado de cliente. Foram realizados diversos testes de avaliação do sistema que demonstraram estar o mesmo a operar correctamente e de forma eficiente. ABSTRACT: The characteristics of Internet traffic are becoming more and more complex due to the large and growing diversity of applications, the drastic differences in user behaviours and the mobility of users and devices, the complexity of traffic generation and control mechanisms, and the increasing diversity of the link type and quality. In such an environment, it is inevitable that network management tasks will rely heavily on (real-time) traffic measurements. Due to the large amounts of data that need to be processed and stored, measurement platforms have to become more distributed, allowing for scattered storage, replication and efficient retrieval of measurement data, possibly mimicking the peer-to-peer (P2P) paradigm. In this dissertation we describe the specification, development and evaluation of a distributed traffic measurement system with a P2P architecture, which provide network managers with a tool to remotely configure third-party monitoring modules installed at different points of the network in order to perform test measurements. The system can also be used as a large-scale measurement infrastructure in a community-oriented network where Internet users may share some processing power and storage space of their machines to allow other Internet users (e.g. researchers) to perform measurements, to retrieve and share the obtained results. The system is based on a hierarchical overlay network organized in measurement areas. The overlay network is formed by two types of nodes, called probes and super-probes, which perform the measurements and store the measurement results. Super-probes have the specific role of providing connection among measurement areas and manage the exchange of messages between the network and the probes connected to them. The topology of the overlay network can change dynamically, with nodes being inserted and removed on-the-fly, and probes being transformed in superprobes and vice-versa, in response to changes in the available resources. The nodes collect two types of measured data: Light Data Files (LDFs) and Heavy Data Files (HDFs). LDFs store the average round-trip time from each superprobe to every element it is connected to and are replicated in all super-probes, providing a coarse but widely available view of the network status. HDFs contain the results of detailed measurements carried out at the packet or flow level and can be replicated at some nodes of the overlay network. Replications are spread over the overlay network taking into account the resources available at nodes, so as to provide high resilience to failures. Users can configure traffic measurements and search the overlay network for measurement data through the so-called client element. The various tests carried out in the system have shown that it performs correctly and efficiently.
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Luan, Hao. "Peer-to-peer content distribution network design /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?ECED%202007%20LUAN.
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Tsang, Pui-sze, and 曾倍思. "Performance analysis on peer-to-peer file distribution." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45160107.
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Makris, Athanasios, and Andreas Strikos. "Daedalus: A media agnostic peer-to-peer architecture for IPTV distribution." Thesis, KTH, Kommunikationssystem, CoS, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91855.
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IPTV is gaining increasing attention. It is an expanding field where a lot of people are working hard to solve the problems that delay its wide-spread use. One major problem is that the existing IPTV distribution mechanisms do not seem to work well when applied on a large scale. Especially, IP multicast does not seem to meet the requirements of highly demanding IPTV services. In contrast, peer-to-peer architectures for distributing content have been available for a number of years (since the late 1990’s), and their success suggests that this is a promising alternative means of distributing content. Although peer-to-peer architectures are well known for file transfer, this kind of architecture has been used in this thesis for distributing streaming video flows. We combine results from two different approaches - IPTV and peer-to-peer systems - as part of our design and implementation of a new solution for distributing IPTV. Our proposal aims to avoid any weaknesses that the existing solutions have, whilst offering a viable solution for distributing live content.Intresset kring IPTV ökar hela tiden, och många människor arbetar på att lösa de problem som hindrar området från att växa snabbt. Ett av huvudproblemen är att den existerande IPTV-distributionstekniken inte fungerar bra då den appliceras på stora lösningar. Bland de största problemen är att IP-Multicast inte möter de krav som marknaden ställer på global distribution av material. I motsats till detta har peer-to-peer teknik, som funnits sedan 90-talet, visat sin styrka för fil distribution på en mycket global skala på existerande infrastruktur. I denna uppstats kombinerar vi dessa två områden för att utröna vilka möjligheterna som finns för att optimera kostnaden för distrubition av live-tv samtidigt som vi försöker att undvika de svagheter som normalt associeras med de olika arkitekturerna. Vårt mål är att utnyttja de bästa egenskaperna från de olika teknikerna för att skapa en livsduglig och långsiktig lösning för TV-distribution.
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Bai, Xi. "Peer-to-peer, multi-agent interaction adapted to a web architecture." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/7968.
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The Internet and Web have brought in a new era of information sharing and opened up countless opportunities for people to rethink and redefine communication. With the development of network-related technologies, a Client/Server architecture has become dominant in the application layer of the Internet. Nowadays network nodes are behind firewalls and Network Address Translations, and the centralised design of the Client/Server architecture limits communication between users on the client side. Achieving the conflicting goals of data privacy and data openness is difficult and in many cases the difficulty is compounded by the differing solutions adopted by different organisations and companies. Building a more decentralised or distributed environment for people to freely share their knowledge has become a pressing challenge and we need to understand how to adapt the pervasive Client/Server architecture to this more fluid environment. This thesis describes a novel framework by which network nodes or humans can interact and share knowledge with each other through formal service-choreography specifications in a decentralised manner. The platform allows peers to publish, discover and (un)subscribe to those specifications in the form of Interaction Models (IMs). Peer groups can be dynamically formed and disbanded based on the interaction logs of peers. IMs are published in HTML documents as normal Web pages indexable by search engines and associated with lightweight annotations which semantically enhance the embedded IM elements and at the same time make IM publications comply with the Linked Data principles. The execution of IMs is decentralised on each peer via conventional Web browsers, potentially giving the system access to a very large user community. In this thesis, after developing a proof-of-concept implementation, we carry out case studies of the resulting functionality and evaluate the implementation across several metrics. An increasing number of service providers have began to look for customers proactively, and we believe that in the near future we will not search for services but rather services will find us through our peer communities. Our approaches show how a peer-to-peer architecture for this purpose can be obtained on top of a conventional Client/Server Web infrastructure.
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Edge, Dion M. (Dion Miguel) 1975. "Architecture and optimization for a peer-to-peer content management system." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28300.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.Includes bibliographical references (leaves 87-88).
This thesis will explore the design and optimization of a peer-to-peer network application as a solution to complex content management problems. Currently, most content management systems are expensive, cumbersome and inflexible custom solutions that require knowledge workers to change their work habits. Peer-to-peer offers a uniquely decentralized and, potentially, scalable solution for knowledge workers by providing a simple and visual tool for file management, meta-data description and collaboration. This thesis will reference a client beta designed and developed by the author. Additionally, this thesis will address the need for content management solutions, the state of current solutions and a requirements document for a solution. Subsequently, the thesis will explore the design aspects of a peer-to-peer content management solution. As well as designing and developing a P2P client as proof of concept, this thesis will mathematically explore the implications of scaling the client to many users and methods to optimize performance. The last few chapters will cover the implementation of the client, proposed next steps for development and analysis of alternative architectures.
by Dion M. Edge.
S.M.
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Wilson, Dany. "Architecture for a Fully Decentralized Peer-to-Peer Collaborative Computing Platform." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32790.
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We present an architecture for a fully decentralized peer-to-peer collaborative computing platform, offering services similar to Cloud Service Provider’s Platform-as-a-Service (PaaS) model, using volunteered resources rather than dedicated resources. This thesis is motivated by three research questions: (1) Is it possible to build a peer-to-peer col- laborative system using a fully decentralized infrastructure relying only on volunteered resources?, (2) How can light virtualization be used to mitigate the complexity inherent to the volunteered resources?, and (3) What are the minimal requirements for a computing platform similar to the PaaS cloud computing platform?
We propose an architecture composed of three layers: the Network layer, the Virtual layer, and the Application layer.
We also propose to use light virtualization technologies, or containers, to provide a uniform abstraction of the contributing resources and to isolate the host environment from the contributed environment. Then, we propose a minimal API specification for this computing platform, which is also applicable to PaaS computing platforms.
The findings of this thesis corroborate the hypothesis that peer-to-peer collaborative systems can be used as a basis for developing volunteer cloud computing infrastructures. We outline the implications of using light virtualization as an integral virtualization primitive in public distributed computing platform. Finally, this thesis lays out a starting point for most volunteer cloud computing infrastructure development effort, because it circumscribes the essential requirements and presents solutions to mitigate the complexities inherent to this paradigm.
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Stutzbach, Daniel. "Measuring and characterizing properties of peer-to-peer systems /." view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1280151121&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2006.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 214-227) and index. Also available for download via the World Wide Web; free to University of Oregon users.
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Cheng, Kan-Leung. "Offering differentiated services for peer-to-peer streaming /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?COMP%202006%20CHENG.
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Magharei, Nazanin 1979. "Peer-to-peer streaming: Design and challenges." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/11089.
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xxii, 413 p. : ill.Streaming multimedia content over the Internet is extremely popular mainly due to emerging applications such as IPTV, YouTube and e-learning. All these applications require simultaneous streaming of multimedia content from one or multiple sources to a large number of users. Such applications impose unique requirements in terms of server bandwidth and playback delay which are difficult to achieve in a scalable fashion with the traditional client-server architecture. Peer-to-peer (P2P) overlays offer a promising approach to support scalable streaming applications, that we broadly refer to as "P2P streaming". Design of a scalable P2P streaming mechanism that accommodates heterogeneity of peers' bandwidth and copes with dynamics of peer participation while ensuring in-time delivery of the multimedia content to individual peers is extremely challenging. Besides these fundamental challenges, P2P streaming applications are facing practical issues such as encouraging peers' contribution and decreasing the costly inter-ISP P2P traffic. In this dissertation, we study several aspects of live P2P streaming with the goal of improving the performance of such systems. This dissertation can be categorized into two parts as follows. ( i ) We present the design and evaluation of a mesh-based live P2P streaming mechanism, called PRIME. Further, we perform a head-to-head comparison between the two approaches on live P2P streaming, namely tree-based and mesh-based. We demonstrate the superiority of the mesh-based approach. In the quest for a systematic comparison of existing mesh-based solutions on live P2P streaming, we leverage the insights from our design in PRIME and propose an evaluation methodology. Utilizing the evaluation methodology, we compare the performance of existing mesh-based live P2P streaming solutions. ( ii ) From a more practical perspective, we tackle some of the existing practical issues in the deployment of live P2P streaming applications, namely providing incentives for participating peers to contribute their resources and designing ISP-friendly live P2P streaming protocols with the ultimate goal of reducing costly inter-ISP traffic. In the end, this dissertation reveals fundamental trade-offs in the design, comparison and meaningful evaluation of basic and practical live P2P streaming mechanisms under realistic settings. This dissertation includes my previously published and my co-authored materials.
Committee in charge: Prof. Reza Rejaie, Chair; Prof. Virginia Lo; Prof. Jun Li; Prof. David Levin; Prof. Markus Hofmann
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Youll, James E. (James Edward) 1964. "Peer to peer transactions in agent-mediated electronic commerce." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8267.
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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2001.Includes bibliographical references (p. 171-176).
This thesis proposes a new approach to electronic markets that overcomes the shortcomings of existing electronic markets through software agent-driven, peer-to-peer, iterative negotiations. Contemporary electronic markets commonly capture both the customs and shortcomings of traditional practice. Rule-based and bound to traditional models, contemporary electronic markets are overly controlling, segregated, inflexible, weakly automated and fixated on price. Many prior attempts to interpose electronic exchanges in existing markets have failed or encountered resistance from traders. Traders' resistance is interpreted here as a call for systems that bend to the will of traders while channeling self-interested actions toward healthy market practices. The Atomic Market is both a model for an agent-based, peer-to-peer marketplace, and a working system that shows the model in operation. The Atomic Market architecture defines a decentralized marketplace wholly controlled by traders through a new protocol for distributed negotiation. The demonstration system is a collection of independent software agents that pursue economic exchanges via the Atomic Market methodology. In the Atomic Market, multiple agents resolve their self-interests though cycles of rewriting a "contract" comprised of descriptive, flexible terms tailored to the needs of each trader. The Atomic Market interprets the Contract Net Protocol as a message-passing system for economic negotiations, in which agents conduct broad, parallel searches to discover opportunities and trading partners in an open marketplace. One of the first implementations of a decentralized, peer-to-peer agent marketplace, the Atomic Market brings together three features not found in contemporary e-commerce systems: decentralization, component-based transactions and open-ended outcomes. Buyers and sellers benefit from the exchange of detailed needs, offers, contingencies and external conditions as they define and negotiate both the substance and terms of a transaction.
James E. Youll.
S.M.
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Han, Jinsong. "Anonymous and trustworthy computing in peer-to-peer systems /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CSED%202007%20HAN.
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Bartlang, Udo. "Architecture and methods for flexible content management in peer-to-peer systems." Wiesbaden Vieweg + Teubner, 2009. http://d-nb.info/1000248992/04.
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Bartlang, Udo. "Architecture and methods for flexible content management in peer-to-peer systems." Wiesbaden : Vieweg + Teubner Research, 2010. http://site.ebrary.com/id/10383036.
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Tsietsi, Mosiuoa. "Prototyping a peer-to-peer session initiation protocol user agent /." [S.l. : s.n.], 2008. http://eprints.ru.ac.za/1115/.
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Jin, Xin, and 靳鑫. "Peer-to-peer system design: incentives and evolution of cooperation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50662235.
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The persistence of cooperation is a longstanding problem in the social and biological sciences. Recent advances of peer-to-peer (P2P) networks manifest as a promising platform to experiment and contribute to theories and algorithms on cooperation. In this thesis, by and large, we view P2P systems as an economy in which incentives are critical to stimulate contribution. Indeed, a P2P system can be considered as a society where different behaviors can emerge, and an empirical platform to understand cooperation and mimic evolving population. Specifically, we consider the problem of cooperation from two perspectives.
First and foremost, autonomous nodes are strategic and selfish, who are reluctant to cooperate solely for public good. We investigate incentive scheme design for cooperation in P2P live media streaming networks. The general approach of protocol decomposition shows that practical incentives can only be guaranteed by efficient peer selection, due to stringent playback deadlines. Striker strategy is then proposed so as to align the optimal peer selection of heterogeneous nodes with social welfare maximization, the efficiency of which is validated by repeated game modeling and extensive simulations. The hidden philosophy is to coerce non-cooperative peers into cooperation by collectively implementing punishment threats. This is analogous to strikes and coercion implemented by organizations like unions in human society.
On the other hand, just as node selfishness, competition and struggle for survival raise another problem for cooperation. Similar to human society and biological systems, we envision that diverse strategies—some are more exploitative, while others more altruistic—could be deployed by selfish participants to compete against interacting nodes and gain performance advantages. In such a variegated environment, our coevolutionary perspective aims to understand cooperation and rationalize the coexistence and success of diverse behaviors. Population games and evolutionary game theory provide analytical tractability, while learning and evolutionary dynamics are proposed to evolve strategies.published_or_final_version
Electrical and Electronic Engineering
Doctoral
Doctor of Philosophy
24
Yiu, Wai-Pun. "Offering reliability and interactivity for peer-to-peer streaming /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20YIU.
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Xu, Jialing, and 徐加羚. "On live data streaming over peer-to-peer networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44904472.
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Valiveti, Kalyan. "Agent Extensions for Peer-to-Peer Networks." Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4382/.
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Peer-to-Peer (P2P) networks have seen tremendous growth in development and usage in recent times. This attention has brought many developments as well as new challenges to these networks. We will show that agent extensions to P2P networks offer solutions to many problems faced by P2P networks. In this research, an attempt is made to bring together JXTA P2P infrastructure and Jinni, a Prolog based agent engine to form an agent based P2P network. On top of the JXTA, we define simple Java API providing P2P services for agent programming constructs. Jinni is deployed on this JXTA network using an automated code update mechanism. Experiments are conducted on this Jinni/JXTA platform to implement a simple agent communication and data exchange protocol.
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Tsietsi, Mosiuoa Jeremia. "Prototyping a peer-to-peer session initiation protocol user agent." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1006603.
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The Session Initiation Protocol (SIP) has in recent years become a popular protocol for the exchange of text, voice and video over IP networks. This thesis proposes the use of a class of structured peer to peer protocols - commonly known as Distributed Hash Tables (DHTs) - to provide a SIP overlay with services such as end-point location management and message relay, in the absence of traditional, centralised resources such as SIP proxies and registrars. A peer-to-peer layer named OverCord, which allows the interaction with any specific DHT protocol via the use of appropriate plug-ins, was designed, implemented and tested. This layer was then incorporated into a SIP user agent distributed by NIST (National Institute of Standards and Technology, USA). The modified user agent is capable of reliably establishing text, audio and video communication with similarly modified agents (peers) as well as conventional, centralized SIP overlays.
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Sharan, Ajitabh Sharan Ajitabh. "Exploiting semantic locality to improve peer-to-peer search mechanisms /." Online version of thesis, 2006. https://ritdml.rit.edu/dspace/handle/1850/2891.
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Zou, Li. "State and file sharing in peer-to-peer systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/8093.
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Fan, Bo Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Sharing network measurements on peer-to-peer networks." Publisher:University of New South Wales. Electrical Engineering & Telecommunications, 2007. http://handle.unsw.edu.au/1959.4/40762.
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With the extremely rapid development of the Internet in recent years, emerging peer-to-peer network overlays are meeting the requirements of a more sophisticated communications environment, providing a useful substrate for applications such as scalable file sharing, data storage, large-scale multicast, web-cache, and publish-subscribe services. Due to its design flexibility, peer-to-peer networks can offer features including self-organization, fault-tolerance, scalability, load-balancing, locality and anonymity. As the Internet grows, there is an urgent requirement to understand real-time network performance degradation. Measurement tools currently used are ping, traceroute and variations of these. SNMP (Simple Network Management Protocol) is also used by network administrators to monitor local networks. However, ping and traceroute can only be used temporarily, SNMP can only be deployed at certain points in networks and these tools are incapable of sharing network measurements among end-users. Due to the distributed nature of networking performance data, peer-to-peer overlay networks present an attractive platform to distribute this information among Internet users. This thesis aims at investigating the desirable locality property of peer-to-peer overlays to create an application to share Internet measurement performance. When measurement data are distributed amongst users, it needs to be localized in the network allowing users to retrieve it when external Internet links fail. Thus, network locality and robustness are the most desirable properties. Although some unstructured overlays also integrate locality in design, they fail to reach rarely located data items. Consequently, structured overlays are chosen because they can locate a rare data item deterministically and they can perform well during network failures. In structured peer-to-peer overlays, Tapestry, Pastry and Chord with proximity neighbour selection, were studied due to their explicit notion of locality. To differentiate the level of locality and resiliency in these protocols, P2Psim simulations were performed. The results show that Tapestry is the more suitable peer-to-peer substrate to build such an application due to its superior localizing data performance. Furthermore, due to the routing similarity between Tapestry and Pastry, an implementation that shares network measurement information was developed on freepastry, verifying the application feasibility. This project also contributes to the extension of P2Psim to integrate with GT-ITM and link failures.
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Zou, Li. "State and file sharing in peer-to-peer systems." Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-06072004-131435/unrestricted/zou%5Fli%5F200405%5Fphd.pdf.
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Leung, Man-Fung. "Peer-to-peer collaborative streaming among mobiles for video broadcasting /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?COMP%202006%20LEUNG.
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Niedermayer, Heiko [Verfasser]. "Architecture and components of secure and anonymous peer-to-peer systems / Heiko Niedermayer." München : Network Architectures and Services, TUM, 2010. http://d-nb.info/100439716X/34.
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Guo, Dingding, and 郭丁丁. "On the efficiency of resources utilization in strategic peer-to-peer systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206652.
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Peer-to-peer (P2P) systems have achieved outstanding success during the past decades and much efforts has been put into investigating incentive mechanisms for strategic P2P networks. In the numerous studies of P2P system, efficient resource utilization has always been a critical factor in designing incentive schemes. Most existing studies try to encourage strategic peers to contribute more to the system, in order to maximize the resources. However, without considering how to effectively measure contributions and without adopting well-designed trading policies, simply motivating more contributions could lead to outcomes that do not match the original intention.
This thesis, therefore, focuses on the investigation of efficient resource utilization in strategic P2P systems. First, it is found that increased contributions in terms of upload rate does not necessarily lead to better system performance. Observing that different chunks have different values to both the system and individual peers, a value-based metric is devised to measure contributions instead of using rate-based metrics. A variation of BitTorrent is also proposed, called value-based BitTorrent (VBT). VBT is found to effectively punish the strategic behaviors of an underreporting chunk map, and there is a positive correlation between investment and return for cooperative peers in VBT networks. Moreover, VBT always outperforms BitTorrent in terms of system performance.
Second, taking the chunk value in the reciprocity process into consideration, the overpayment problem in a BitTorrent network is investigated, and four side effects of overpayment are identified. A new scheme is proposed to visualize overpayment and a series of metrics is proposed based on this method to quantify overpayment. The proposed value-based approach is found to be able to alleviate the degree of overpayment and consequently relieve the side effects of overpayment.
Third, the performance of popular protocols in a P2P file-sharing system is investigated from the perspective of overpayment. These protocols are studied in two directions, when the measurement metrics are varied and when trading policy becomes tighter. The correlations between fairness, performance, and robustness are also examined.
Finally, because overpayment is a fundamental problem of improper price setting, and auction is a widely used and effective method in setting prices in distributed systems. Auction is analytically proved that it is able to lead to optimal price without overpayment. However, most existing auction schemes are based on credit, which could induce a huge overhead in maintaining a monetary system, and monetary systems also have many inherent problems, such as inflation. The efficacy of applying an auction-like approach in P2P systems without money is investigated. A simplified version of the barter-based auction-like approach is tested in P2P file sharing and its overpayment degree is evaluated. Moreover, a novel barter-based auction-like approach is proposed for a P2P streaming system, and it is found that it can successfully punish strategic behaviors, with overall system performance outperforming a tit-for-tat strategy.published_or_final_version
Electrical and Electronic Engineering
Doctoral
Doctor of Philosophy
35
Oztoprak, Kasim. "Hybrid Cdn P2p Architecture For Multimedia Streaming." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609400/index.pdf.
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In this thesis, the problems caused by peer behavior in peer-to-peer (P2P)
video streaming is investigated. First, peer behaviors are modeled using two
dimensional continuous time markov chains to investigate the reliability of P2P
video streaming systems. Then a metric is proposed to evaluate the dynamic
behavior and evolution of P2P overlay network. Next, a hybrid geographical
location-time and interest based clustering algorithm is proposed to improve
the success ratio and reduce the delivery time of required content. Finally,
Hybrid Fault Tolerant Video Streaming System (HFTS) over P2P networks has been designed and offered conforming the required Quality of Service (QoS) and
Fault Tolerance. The results indicate that the required QoS can be achieved in
streaming video applications using the proposed hybrid approach.
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Bian, Li S. M. Massachusetts Institute of Technology. "Llifelog : discovering and evaluating research projects through peer-to-peer exchange." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/76514.
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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 62-63).
Llifelog is a web platform for discovering, evaluating, and exchanging research projects among students and researchers from both academia and industry. The goal of Llifelog is foster a community of critique among students and researchers in a project market. Those who engage in the market answer the call "find out how your work, projects, and ideas are valued in the community." The unique contribution of the Llifelog system lies in designing market-based mechanisms that stimulate the project exchange while maintaining information confidentiality, and devising a peer-to-peer, direct communication channel between project creators and project viewers. In this thesis, I explain how such market mechanism results more objective evaluation compared to other existing rating mechanisms online. A virtual credit system, Truons, is used in this web platform to facilitate the project evaluation and exchange. The website was built using Java, MySQL, Apache Tomcat, HTML, CSS, and Javascript and hosted on an Ubuntu server. It also uses a Natural Language Processing engine, AlchemyAPI, and various image processing techniques. The platform was tested among about 305 users with 74 projects within 3 weeks. User feedback was also gathered after the testing to further understand the context and rationale for user behavior on the web platform.
by Li Bian.
S.M.
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Zhang, Xin, and 张昕. "Gossip-based publish-subscribe systems in peer-to-peer networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208013.
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Peer-to-peer (P2P) paradigm, for its scalability and low cost management, is widely used in today’s network. Based on the typical designs for request/response services, a lot of efforts have been made to support publish-subscribe services in P2P networks. Gossip-based publish-subscribe system, which is commonly used in unstructured P2P networks, can provide great flexibility in query language and does not require special efforts on maintaining topology. The purpose of our work is to investigate effective and efficient mechanisms to build gossip-based publish-subscribe systems in unstructured P2P networks. Specifically, the probabilistic bi-quorum system (PBQS), for its assurance in effectiveness, becomes the object of our study.
Uniform sampling is a fundamental tool to construct PBQS. By adopting uniform sampling, PBQS provides a bound on the likelihood that data messages will find a copy of the subscription. A random walk of length O(log n) is commonly used to gain a uniform sample on an expander graph of size n. To obtain a multitude of uniform samples thus requires an equivalent number of random walks of length O(log n) each. A number of works have relied on the Chernoff bound to analytically reduce the overhead needed to obtain a multitude of uniform samples. Besides, researchers have also shown that it is not necessary to replicate both data and query on uniformly chosen nodes. Alternatively, BubbleStorm performs controlled flooding on a constructed overlay to build PBQS. BubbleStorm does not require nodes forming a bubble to be uniformly chosen at random, and the probabilistic bound computed by BubbleStorm is different from uniform sampling based PBQS.
In this thesis, we first show that the Chernoff bound on the statistical properties of samples collected from a random walk does not help in selecting uniformly random nodes. We then re-examine the role of uniform sampling in PBQS, and found that when multiple data answer a single subscription, it is sufficient and necessary for each data to be distributed uniformly at random. Looking into BubbleStorm, we examine more closely the probabilistic bound provided by this system. We found that, unlike uniform sampling based PBQS, the bubble intersection in BubbleStorm is distance dependent. Given a specific pair of publisher-subscriber, the data may never find the subscription. We further investigate the topology construction and found that re-creating topology prior to each controlled flooding or keeping topology with high degree of churn can help alleviate the distance dependency problem. We arrive at the conclusion that BubbleStorm construction is equivalent to caching of random walks. We show that re-using this cache to obtain samples over time leads to degradation of uniformity of the samples. We evaluate topology re-wiring as a simple method to keep the cache fresh, thereby benefiting from the low latency of controlled flooding without degrading the uniformity of samples over time.published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy
38
Kwong, Kin Wah. "Topology construction and searching algorithms for heterogeneous peer-to-peer networks /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202005%20KWONG.
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Chan, Kam-Hung. "SPANC : optimizing scheduling delay for peer-to-peer live streaming /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CSED%202009%20CHANK.
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Pradeep, Aakash. "P2PHDFS: AN IMPLEMENTATION OF STATISTIC MULTIPLEXED COMPUTING ARCHITECTURE IN HADOOP FILE SYSTEM." Master's thesis, Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/214757.
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Computer and Information ScienceM.S.
The Peer to Peer Hadoop Distributed File System (P2PHDFS) is designed to store and process extremely large-scale data sets reliably. This is a first attempt implementation of the Statistic Multiplexed Computing Architecture concept proposed by Dr. Shi for the existing Hadoop File System (HDFS) to eliminate all single point failures. Unlike HDFS, in P2PHDFS every node is designed to be equal and behaves as a file system server as well as slave, which enable it to attain higher performance and higher reliability at the same time as the infrastructure up scales. Due to the data intensive nature, a full implementation of P2PHDFS must address CAP Theorem challenges. This MS project is only intended as the ground breaking point using only sequential replication at this time.
Temple University--Theses
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Li, Yung-Ming. "Essays in peer-to-peer content distribution networks : scale, formation, and pricing /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/8765.
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Leung, Ka-ho Andrew. "Localized topology control in wireless peer-to peer file sharing networks." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B32048208.
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Leung, Ka-ho Andrew, and 梁嘉浩. "Localized topology control in wireless peer-to peer file sharing networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B32048208.
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Tang, Ho-Shing. "POPCA : optimizing segment caching for peer-to-peer on-demand streaming /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20TANG.
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Wen, Zheng, and 文峥. "Algorithm design of layered peer-to-peer video on demand streaming networks." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50434433.
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Peer-to-peer (P2P) video streaming has become a very popular and cost-effective solution to provide video-on-demand (VoD) streaming service to a large group of Internet users. Recent advances of layered video coding are shown to be promising in addressing the problem of receiver heterogeneity in P2P streaming networks. The key idea is to encode a raw video into multiple non-overlapped layers. Peers in the network can enjoy different streaming qualities by subscribing to different number of layers according to their specific network bandwidth. In this thesis, a systematic and comprehensive study of layered P2P VoD streaming networks is conducted.
We first investigate the overlay construction problem that concerns the strategy of forming a logical overlay network for peers to exchange data pieces. We propose a neighbor relationship management algorithm to maintain a stable yet diversified neighbor set to facilitate adding or dropping a video layer, i.e. layer adaptation. Subsequently, an incentive scheme is designed to differentiate neighbors’ contributions at different layers, and a peer is allowed to adjust its number of neighbors according to its average service response time.
We then develop an efficient layer adaptation algorithm for adjusting the number of video layers a peer subscribes to. We use a sliding buffer window for video piece scheduling, and make use of the time difference between the playback point and the starting point of the sliding window to initiate the process of adding or dropping a layer. A probing period is also introduced to ensure the adding decision is indeed correct.
We next focus on designing piece scheduling algorithm for video data exchange among peers. At each peer, a utility function for calculating the relative importance of each missing video data piece is designed. In piece scheduling, a peer prefers a piece with higher utility value. We show that our utility based piece scheduling algorithm yields better video quality than conventional approaches.
Last but not least, we study the request peer selection problem for identifying the most suitable neighbor for a peer to make a piece request. Two algorithms are designed, smallest service response time first (SSF) and closest playback point first (CPF). SSF ensures peers with larger uplink bandwidths to serve more requests, and CPF encourages a newly joined peer to contribute its uplink bandwidth as quickly as possible. We show that there exists a sweet spot by properly combining the two together.
Although our algorithms are presented sequentially in addressing each of the problems above, they do interact with each other. Throughout our study, a comprehensive packet-level simulator is used to closely examine and analyze such interactions. With that, our algorithms are judicially designed and fine-tuned for best performance. To the best of our knowledge, our in-house developed simulator is the most comprehensive packet-level simulator for layered P2P VoD streaming.published_or_final_version
Electrical and Electronic Engineering
Doctoral
Doctor of Philosophy
46
Meng, Xiang, and 孟翔. "Bandwidth partition strategies for minimizing peer-to-peer multi-file distribution time." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B5089996X.
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Peer-to-Peer (P2P) technology has been developed rapidly during the past few years. Due to its superiorities on robustness and scalability, P2P technology has been viewed as a promising networking technology and many studies have been done on how to improve P2P technology.
P2P file distribution, as a major application of P2P technology, has also been studied a lot. The amount of time required for all peers to get the file has been considered as a major optimization metric, which we refer as the file distribution time. Researchers have proposed protocols to minimize the file distribution time for different cases. However, most of the existing works are based on the single-file scenario. On the other hand, studies show that in a file sharing application, users may download multiple files at the same time. In this thesis, we analyze the file distribution time for the distribution of multiple files in both wired and wireless networks.
We develop explicit expressions for lower bound of time needed to distribute multiple files in a heterogeneous P2P fluid model. Unlike the single-file scenario, we demonstrate that the theoretical lower bound in multi-file scenario is not always achievable. With a comprehensive consideration of all the configurations, we develop algorithms to partition the bandwidth of all the peers for a particular file such that the file distribution time is optimal.published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy
47
Xie, Susu. "The large scale peer-to-peer (P2P) live streaming in the Internet /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20XIE.
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Wu, Yunhui. "Agent behavior in peer-to-peer shared ride systems /." Connect to thesis, 2007. http://eprints.unimelb.edu.au/archive/00003214.
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Hei, Xiaojun. "End-to-end network measurement and its applications in peer-to-peer networks /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20HEI.
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Gilmore, John Sebastian. "A state management and persistency architecture for peer-to-peer massively multi-user virtual environments." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80268.
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Thesis (PhD)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Recently, there has been significant research focus on Peer-to-Peer (P2P) Massively Multi-user Virtual Environments (MMVEs). A number of architectures have been presented in the literature to implement the P2P approach. One aspect that has not received sufficient attention in these architectures is state management and state persistency in P2P MMVEs. This work presents and simulates a novel state management and persistency architecture, called Pithos. In order to design the architecture, an investigation is performed into state consistency architectures, into which the state management and persistency architecture should fit. A novel generic state consistency model is proposed that encapsulated all state consistency models reviewed. The requirements for state management and persistency architectures, identified during the review of state consistency models, are used to review state management and persistency architectures currently receiving research attention. Identifying some deficiencies present in current designs, such as lack of fairness, responsiveness and scalability, a novel state management and persistency architecture, called Pithos, is designed. Pithos is a reliable, responsive, secure, fair and scalable distributed storage system, ideally suited to P2P MMVEs. Pithos is implemented in Oversim, which runs on the Omnet++ network simulator. An evaluation of Pithos is performed to verify that it satisfies the identified requirements. It is found that the reliability of Pithos depends heavily on object lifetimes. If an object lives longer on average, retrieval requests are more reliable. An investigation is performed into the factors influencing object lifetime. A novel Markov chain model is proposed which allows for the prediction of objects lifetimes in any finite sized network, for a given amount of redundancy, node lifetime characteristics and object repair rate.
AFRIKAANSE OPSOMMING: Onlangs is daar ’n beduidende navorsingsfokus op Eweknie Massiewe Multi-gebruiker Virtuele Omgewings (MMVOs). ’n Aantal argitekture is in die literatuur beskikbaar wat die eweknie benadering voorstel. Een aspek wat nie voldoende aandag ontvang in hierdie argitekture nie is toestandsbestuur en toestandsvolharding in eweknie MMVOs. Hierdie werk ontwerp en simuleer ’n nuwe toestandsbestuur- en toestandsvolhardingargitektuur genaamd Pithos. Ten einde die argitektuur te ontwerp is ’n ondersoek uitgevoer in toestandskonsekwentheidargitekture, waarin die toestandsbestuur- en toestandsvolhardingargitektuur moet pas. ’n Nuwe generiese toestandskonsekwentheidargitektuur word voorgestel wat alle hersiene toestandskonsekwentheid argitekture vervat. Die vereistes vir die toestandsbestuur- en toestandsvolhardingargitekture, geidentifiseer tydens die hersiening van die toestandskonsekwentheidargitekture, word gebruik om toestandsbestuuren toestandsvolhardingargitekture te hersien wat tans navorsingsaandag geniet. Identifisering van sekere leemtes teenwoordig in die huidige ontwerpe, soos ’n gebrek aan regverdigheid, responsiwiteit en skaleerbaarheid, lei tot die ontwerp van ’n nuwe toestandsbestuur- en toestandsvolhardingargitektuur wat Pithos genoem word. Pithos is ’n betroubare, responsiewe, veilige, regverdige en skaleerbare verspreide stoorstelsel, ideaal geskik is vir eweknie MMVOs. Pithos word geïmplementeer in Oversim, wat loop op die Omnet++ netwerk simulator. ’n Evaluering van Pithos word uitgevoer om te verifieer dat dit voldoen aan die geïdentifiseerde behoeftes. Daar is gevind dat die betroubaarheid van Pithos afhang van die objek leeftyd. As ’n objek gemiddeld langer leef, dan is herwinning versoeke meer betroubaar. ’n Ondersoek word uitgevoer na die faktore wat die objek leeftyd beïnvloed. ’n Nuwe Markov ketting model word voorgestel wat voorsiening maak vir die voorspelling van objek leeftye in eindige grootte netwerke, vir gegewe hoeveelhede van oortolligheid, nodus leeftyd eienskappe en objek herstelkoers.