Replication is an important technique in peer-to-peer environment, where it increases data availability and accessibility to users despite site or communication failure. However, determining the number of replication and where to replicate the data are the major issues. This paper proposes a hybrid replication model for fixed and ad hoc network in order to achieve high data availability. For the fixed network, a data will be replicated synchronously in a diagonal manner of logical grid structure, while for the ad hoc network, a data will be replicated asynchronously based on commonly visited sites for each user. In comparison to the Grid structure technique, diagonal replication technique (DRG) on fixed network requires lower communication cost for an operation, while providing higher data availability, which is preferred for large systems.