如果我想授权我的客户端应用程序之间的连接..我怎么样？

I am trying to figure out how to handle authentication and data for client applications who will connect to eachother. In other words, each client app would authenticate to.. and use a central service to find out info about the other client so that they can connect directly. Specifically, what should I deploy to accomplish this and maintain security and privacy?I am trying to figure out how to handle authent