An authorization mechanism within a peer-to-peer network is presented. A central server that operates a centralized data repository search engine within a peer-to-peer network performs authentication and authorization operations with respect to users that access its services. A user at a peer node reviews peer-to-peer search results that have been gathered and returned by the centralized search engine. When the user desires to retrieve a file from another peer node, the user's peer node must obtain an authorization token from the central server, which authenticates the user or has previously authenticated the user. The user's peer node then presents the authorization token along with a request to retrieve the file from the other peer node. After verifying the authorization token, the other peer node responds with the requested file. If the other peer node cannot verify the authorization token, then the other peer node denies access to the file.