  Grid and peer-to-peer (P2P) networks are two ideal technologies for file
sharing. A P2P grid is a special case of grid networks in which P2P
communications are used for communication between nodes and trust management.
Use of this technology allows creation of a network with greater distribution
and scalability. Semantic grids have appeared as an expansion of grid networks
in which rich resource metadata are revealed and clearly handled. In a semantic
P2P grid, nodes are clustered into different groups based on the semantic
similarities between their services. This paper proposes a reputation model for
trust management in a semantic P2P Grid. We use fuzzy theory, in a trust
overlay network named FR TRUST that models the network structure and the
storage of reputation information. In fact we present a reputation collection
and computation system for semantic P2P Grids. The system uses fuzzy theory to
compute a peer trust level, which can be either: Low, Medium, or High. Our
experimental results demonstrate that FR TRUST combines low (and therefore
desirable) a good computational complexity with high ranking accuracy.
