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Peer-to-peer research at Stanford

Abstract

this paper we present recent and ongoing researchprojects of the Peers research group at Stanford University.Section 2 studies the problems relating to locatingresources in P2P systems. Section 3 discusses work onresource allocation and aggregation. Section 4 focuseson issues of resource availability and authenticity. Note,this paper should not be construed as an overview of allresearch problems pertaining to peer-to-peer networks.Only projects connected to our Peers group are...
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... Firstly, digital currency payments do not have the transaction costs as traditional banking systems and payment services. Secondly, digital currencies do not have the same policing and enforcement costs as fiat currencies adding another transaction cost advantage [2]. The security requirements for each involved party of a payment transaction vary but with an equal importance in achieving a higher security level. ...
... Security along with the speed and efficiency are also aimed to be considered in performing transaction verifications. networked payment systems subsequently there is no centralized control over the network [2]. Currently, available payment systems provide complete anonymity to vendors but partial anonymity to customers. ...
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Digital payment systems are an evolving field in present day with the recent enhancements in seamless digital currencies. Thus, despite the benefits of cryptocurrency based digital payments systems, their adoption and diffusion within general payment platform domain are significantly hindered. The blockchain architecture is widely recognized as a promising mechanism to support the management of cryptocurrency related transactions. However, ensuring the security of digital payment transactions is a challenging task due to various security threats and existing prevention mechanisms that are either computationally expensive or domain dependent. Among many, Double Spending is identified as a key security vulnerability. The purpose of this study is to investigate the means of addressing the said security issue by proposing a feasible transaction verification methodology; targeting a common payment platform that integrates different vendor based digital currencies together. The currency miners and the user applications are identified as the core components that cooperate with transactions. Accordingly, a scenario based transaction verification model is designed by considering transaction patterns among miners and user applications. The bitcoin-similar concept of ‘trust network’ is adopted in verifying transactions via building a trusted network among currency miners in the payment platform using digital signatures along with SHA-256 hashing and RSA algorithm. In strengthening the verification level, an approach of acknowledgments is defined associated with a minimum required level of probability. Furthermore, a time constraint is set depending on the peer-to-peer network conditions for a particular transaction to get completed with proper verification.
... They imitate the function of a central server for just a handful number of nodes; hence, they store the file indexes of the nodes under their memberships; the super-nodes themselves connect in a decentralized manner. Gnutella version 2.0 [7,12] and KaZaA [7,12] belong to this model [26,[35][36][37][38]. Table 1 summarizes a comparison of the abovementioned models. ...
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The concept of unstructured Peer-to-Peer (P2P) systems—setting free from any structural constraints—has put forward an appropriate paradigm for sharing a wide assortment of resources in a distributed-sharing manner efficiently. More importantly, unstructured P2P systems’ architecture and concepts have permeated diverse spheres of today’s successful and world-famous computer science areas, including NoSQL databases for excellently sharing data. However, pinpointing any given appropriate resource in such massive systems, namely unstructured P2P systems, is a challenging task; the two of the most dispensable rationales behind this proclaim are large scales of such systems and unstructured nature of overlay networks. Finding a decent resource with low response time, low bandwidth consumption, and high success-rate has played a crucial role in both the overall system performance and the functionality of P2P systems. Briefly, an efficacious resource discovery mechanism is the lifeblood of any productive P2P system. Given these points, in this study, we present an exhaustive survey on state-of-the-art resource discovery mechanisms employed in file-sharing pure unstructured P2P systems; we offer a new resource discovery categorization accordingly. Furthermore, we deeply delve into a plethora of resource searching methods and their merits as well as demerits to furnish the paper with an in-depth evaluation.
... Another benefit of blockchain protocol to our model is its transparency and trust. Distributed ledgers allow each party to reach the data records on a peer-to-peer network (Bawa et al., 2003). This is the core concept of transparency in blockchain models. ...
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... Most of the researchers have used structured P2P networks to construct e-Learning communities [5]. The key challenge in these P2P distributed systems is implementing an efficient content searching and sharing mechanism [13]. ...
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e-Learning is a popular research area in the modern era. Most of the existing e-Learning systems are web based and developed as traditional centralized client/server systems [1], [22], [23]. However, there are few Peer-to-Peer distributed e-Learning platforms in existence. For any e-Learning system content searching and sharing is important. In a distributed e- Learning network locating and sharing learning materials is still a challenge due to high resource and time requirements. In this paper, we propose a lightweight, scalable and low-cost digital content sharing platform which facilitates for general internet-based users to search and share e-Learning materials in an unstructured P2P network. The proposed platform addresses the learning martial search latency problem in distributed e-Learning networks by introducing content advertising and local indexing.
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... In a P2P network [10] [21] workload is distributed among all its nodes (peers). A pool of resources is created using a portion of every peer's resources. ...
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Digital payment systems are an evolving field in present day with the recent enhancements in seamless digital currencies. Thus, despite the benefits of cryptocurrency based digital payments systems, their adoption and diffusion within general payment platform domain are significantly hindered. Blockchain architecture is widely recognized as a promising mechanism to support the management of cryptocurrency related transactions. However, ensuring the security of digital payment transactions is a challenging task due to various security threats and existing prevention mechanisms that are either computationally expensive or domain dependent. Among many, the Man-in-the-Middle attack and Double Spending are identified as key security vulnerabilities. The purpose of this study is to investigate the means of addressing the said security issues by proposing a feasible transaction verification methodology; targeting a common payment platform that integrates different vendor based digital currencies together. The currency miners and the user applications are identified as the core components that cooperate with transactions. Accordingly, a scenario based transaction verification model is designed by considering transaction patterns among miners and user applications. The bitcoin-similar concept of ‘trust network’ is adopted in verifying transactions via building a trusted network among currency miners in the payment platform using digital signatures along with SHA-256 hashing and RSA algorithm. In strengthening the verification level, an approach of acknowledgements is defined associated with a minimum required level of probability. Furthermore, a time constraint is set depending on the peer-to-peer network conditions for a particular transaction to get completed with proper verification. It is explored the strength and feasibility of the proposed methodology in the perspective of transaction verification over man-in-the-middle attack using a probabilistic evaluation where the possibility of a transaction getting verified decreases proportionally when the trusted network of miners getting unhealthy. Also, the double spending prevention is evaluated using the implementation of a mobile-based digital wallet as the proof-of-concept. Keywords: Peer-to-Peer, Man-in-the-Middle Attack, Double Spending, Anonymity, Cryptocurrency, Digital Payment Platform
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