Lattice-based anonymous roaming authentication method

The invention discloses a lattice-based anonymous roaming authentication method. The method comprises a registration stage, an authentication stage, a password changing stage and a session key updating stage. After the intelligent terminal successfully registers in the local agent, the intelligent terminal generates a safe anonymous identity in an authentication stage, an NTRU encryption algorithmis used for carrying out encryption transmission on an authentication message between communication entities, and after authentication succeeds, the intelligent terminal uses the anonymous identity to acquire network service from a foreign agent. In the password changing stage, password changing can be completed only by inputting correct user names and passwords into the intelligent card. In thesession key updating stage, the session key updating operation can be carried out only on the basis that the intelligent terminal and the foreign agent master the old session key. According to the method, extremely high calcul