Peer-to-peer ( P2P ) uses the concept of networking computers in which has no server. Each computer is a server and a client. In such network, users exchange files with each other and this will show through concrete examples, in our example over the uTorrent client. We pass the basic things in terms of P2P networks, from distribution to some basic characteristics. We are talking about the BitTorrent protocol, process operating principle and further implementation of P2P networks. In this final work we use Wireshark tool for monitoring and analyzing network data, in particular the BitTorrent protocol.