VMS Help TCPIP Services, Programming Interfaces, RPC Client Routines, authunix_create, Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Implements UNIX-style authentication parameters. The client uses
    no encryption for its credentials and only sends null verifiers.
    The server sends back null verifiers or optionally a verifier
    that suggests a new shorthand for the credentials.