Nowadays, the growth of data has been increasing. People do data exhanges everytime they want. The increasing number of computer user who exchanges data is coupled with networking capabilities improvement. Because of the increased number of computer users around the world, a need of efficiency data management in WAN (Wide Area Network) environments emerged. Some solutions for those problems are Peer-to-Peer (P2P) networks which allow user in the world to share data without any boundaries. P2P system uses replication to ensure the availabilty of data. P2P network is a network which allocate all computer user in the same position. All the users in P2P network can share any data. Replication is an important thing in P2P network. Replication will replicate the data which wants by many users. This replication system bring many advantages in P2P network. P2P network is an answer for the growing computer user’s problem. Users around the world can share any data through this network. Replication system in this network also play the main part to ensure the availability of data and network performance.