A method is disclosed for enabling stateless server-based pre-shared
secrets. Based on a local key that is not known to a client, a server
encrypts the client's state information. The client's state information
may include, for example, the client's authentication credentials, the
client's authorization characteristics, and a shared secret key that the
client uses to derive session keys. By any of a variety of mechanisms,
the encrypted client state information is provided to the client. The
server may free memory that stored the client's state information. When
the server needs the client's state information, the client sends, to the
server, the encrypted state information that the client stored. The
server decrypts the client state information using the local key. Because
each client stores that client's own state information in encrypted form,
the server does not need to store any client's state information
permanently.