Simulating peer-to-peer networks

Peer-to-Peer (P2P) systems are emerging as a new form of distributed computing with a strong emphasis on self-organization, decentralization, and autonomy of the participating nodes. The characteristics of self-organization, autonomy, and decentralization allow for highly adaptive, robust, and scalable networks, making P2P an increasingly interesting way to design distributed systems. Since the deployment of P2P systems involves significant resources, e.g., hundreds of hosts and users, it is often not possible to run realistic tests prior to the rollout of the system. Consequently, simulation is the only realistic approach for testing or predicting the behavior of large P2P networks. However, the majority of the existing simulators tend to provide limited flexibility in simulating the details of the users, application, protocol, and physical network. In this research, the impact of user behavior, protocol, and physical network characteristic on the overall P2P system are being observed. The aim is to investigate the importance of simulating P2P systems in such detail

Mesmerizer: A Effective Tool for a Complete Peer-to-Peer Software Development Life-cycle

In this paper we present what are, in our experience, the best practices in Peer-To-Peer(P2P) application development and how we combined them in a middleware platform called Mesmerizer. We explain how simulation is an integral part of the development process and not just an assessment tool. We then present our component-based event-driven framework for P2P application development, which can be used to execute multiple instances of the same application in a strictly controlled manner over an emulated network layer for simulation/testing, or a single application in a concurrent environment for deployment purpose. We highlight modeling aspects that are of critical importance for designing and testing P2P applications, e.g. the emulation of Network Address Translation and bandwidth dynamics. We show how our simulator scales when emulating low-level bandwidth characteristics of thousands of concurrent peers while preserving a good degree of accuracy compared to a packet-level simulator

Alpha Multipliers Breadth-First Search Technique for Resource Discovery in Unstructured Peer-to-Peer Networks

Resource discovery in unstructured peer-to-peer (P2P) networks is important in the field of grid computing. Breadth-first search (BFS) is widely used for resource discovery in unstructured P2P networks. The technique is proven to return as many search results as possible. However, the network cost of the technique is high due to the flooding of query messages that can degenerate the performance of the whole network. The objective of this study is to optimise the BFS technique, so that it will produce good search results without flooding the network with unnecessary walkers. Several resource discovery techniques used in unstructured P2P networks are discussed and categorised. P2P simulators that are used for P2P network experiments were studied in accordance to their characteristics such as, scalability, extensibility and support status. Several network topology generators were also scrutinised and selected in order to find out the most real-life like network generation model for unstructured P2P experiments. Multiple combinations of five-tuple alpha multipliers have been experimented to find out the best set to make -BFS. In our test, the -BFS increases the query efficiency of the conventional BFS from 55.67% to 63.15%

Enhanced Resource Discovery Mechanisms for Unstructured Peer-to-Peer Network Environments

This study explores novel methods for resource discovery in unstructured peerto-peer (P2P) networks. The objective of this study is to develop a lightweight resource discovery mechanism suitable to be used in unstructured P2P networks. Resource discovery techniques are examined and implemented in a simulator with high scalability in order to imitate real-life P2P environments. Simulated topology generator models are reviewed and compared, the most suitable topology generator model is then chosen to test the novel resource discovery techniques. Resource discovery techniques in unstructured P2P networks usually rely on forwarding as many query messages as possible onto the network. Even though this approach was able to return many resources, the flooding of the network with query messages have an adverse effect on the network. Flooding the network has undesirable consequences such as degenerative performance of the network, waste of network resources, and network downtime. This study has developed alpha multipliers, a method of controlling query message forwarding to deal with the flooding effect of most resource discovery techniques in unstructured P2P networks. The combination of alpha multipliers and breadth-first search (BFS), ↵-BFS, was able to avoid the flooding effect that usually occurs with BFS. The ↵-BFS technique also increases the combined query efficiency compared to the original BFS. Aside from improving a uninformed search technique such as the BFS, this study also examines the network communication cost of several informed resource discovery techniques. Several issues that arise in informed resource discovery techniques, such as false positive errors, and high network communication costs for queries to update search results are discussed. This detailed analysis forms the basis of a lightweight resource discovery mechanism (LBRDM) that reduces the network communication cost by reducing the number of backward updates inside the network when utilising the blackboard resource discovery mechanism (BRDM). Simulations of BRDM and LBRDM show that the lightweight version can also return an almost identical combined query efficiency than the BRDM. The solution to control query message forwarding in ↵-BFS, and the removal of unnecessary exchange of information in LBRDM open a new perspective on simplifying resource discovery techniques. These approaches can be implemented on other techniques to improve the performance of resource discovery

Sarp Net: A Secure, Anonymous, Reputation-Based, Peer-To-Peer Network

Since the advent of Napster, the idea of peer-to-peer (P2P) architectures being applied to file-sharing applications has become popular, spawning other P2P networks like Gnutella, Morpheus, Kazaa, and BitTorrent. This growth in P2P development has nearly eradicated the idea of the traditional client-server structure in the file-sharing model, now placing emphasizes on faster query processing, deeper levels of decentralism, and methods to protect against copyright law violation. SARP Net is a secure, anonymous, decentralized, P2P overlay network that is designed to protect the activity of its users in its own file-sharing community. It is secure in the fact that public-key encryption is used to guard eavesdroppers during messages. The protocol guarantees user anonymity by incorporating message hopping from node to node to prevent any network observer from pinpointing the origin of any file query or shared-file source. To further enhance the system\u27s security, a reputation scheme is incorporated to police nodes from malicious activity, maintain the overlay\u27s topology, and enforce rules to protect node identity

The trust management framework for peer-to-peer networks

Popularity of peer-to-peer (P2P) networks exposed a number of security vulnerabilities. Among those is a problem of finding reliable communication partners. In this thesis, we present an integrated trust framework for peer-to-peer networks that quantifies the trustworthiness of a peer via reputation-based trust mechanism and anomaly detection techniques. As opposed to other known techniques in P2P networks, our trust management schema is fully decentralized and does not rely on the co-operation of peers. Furthermore, the reputation computation is based on traffic coming from other peers. We also describe an anomaly detection procedure that analyses peer activity on the network and flags potentially malicious behavior by detecting deviation from peer profile. We present integration of our anomaly detection to trust management scheme and study the performance of reputation-based approach using implementation and performance of trust framework through simulation