ZJCShare: A secure cross-platform P2P instant messaging application based on de-centralized structure model

A secure cross-platform instant messaging software based on de-centralized structure model is designed and implemented. This software establishes a p2p overlay network without any central node, each node in this overlay network is called a peer, identified with an UUID, every connection between two peers in the overlay network is completely peer to peer. Two peers who trust each other utilize asymmetrical encryption scheme to create a secure pipe, then use this pipe to transmit a key, this key is used to transfer data between peers using symmetrical encryption scheme. To traverse Nat, data between two peers behind different Nat are bridged by a third peer who can be accessed by both sides, this bridge peer simply transmit data between peers but has not access to the encrypted data content. All peers keep route map for all peers link to it directly and use flooding technique to update the route map.