Um sistema de reputação para ambientes Peer-to-Peer aplicado em redes locais

Abstract

Currently, assign new technologies designed to distributed computing has grown exponentially due to the need for optimization of computing resources. The P2P (Peer-to-Peer) is an example of architecture of distributed systems where the nodes work both in the role of client as the server. The relationship of these nodes presents issues relating to the trust due the communications between them, and since the behavior of nodes is dynamic, security problems are indicated. Thus, a reputation and trust system is one way to control the operation of the network and other problems through methods of reward and punishment. Analyzing the application context, it is notable that use a penalty mechanism to limit bandwidth, as traditionally happens in P2P systems, it is not a viable alternative for LAN environments, due to the resources that this type of network has its own characteristic. Among several other possibilities, limiting access to information about the shared _les shows a concise and applicable manner to establish the penalty in local networks. This study aims to develop a reputation system for local networks, called TrustLP2P. The TrustLP2P proposes a model that adapts aspects of the local network environment at the sime time that related concepts based on other existing reputation systems, making use of reputation and trust values so that the nodes can classify each other. Allied to this, measuring the values of reputation through the participants, the system also aims to reward or penalize the nodes according to their behavior. An application for TrustLP2P is LP2P (Local Peer-to-Peer), a communication platform for distributed environments focused on the sharing of _les, developed by the research project of Computer Networks and Distributed Systems of PIPCA, Unisinos. Thus, the proposed system provides for LP2P an adequate control over the actions of the nodes, through consistent aspects that are described in their model.