Sharing on networks is common nowadays. There are many sites, and users typically must register for an account on each site. Sometimes, sites or services can communicate or share data with each other or cooperate to perform some functions together. Such intercommunication between sites uses a shared network. However, some sites may not be trusted, and the user’s own data, especially passwords, might be exposed or fraudulent. Authentication is needed in order to both identify users and to hide user information via some authorization policies. In this paper, we describe a method for authentication via sessions. This authentication procedure is able to provide authentication of proxies and also allow concealed passwords. It is a little like OpenID1 for websites, which prevents hacks and attacks from malicious servers and allows ordinary network connections. Moreover, it also allows proxy-proving, which permits only registered servers to be agents of a requesting user to request data from other servers.