An authentication server generates a security token to be used by a client for accessing multiple service providers by obtaining a secret key for each specified service provider, generating a saltbase, generating a salt for each service providers using the saltbase, the secret key, and a hashing algorithm, generating a session key that includes the salt, assigning an order to each of the generated salts, and arranging the salts based on the orders, generating a presalt for each provider using the salt for each previous provider, generating a postsalt for each of the specified service providers using the salt for each following provider, generating a blob for each of the specified service providers using the saltbase, the respective presalt, and the respective postsalt, inserting the generated blobs for the specified service providers in the security token, and providing the generated security token to the client workstation.