AUTHINFO SIMPLE
    user password

    This version of AUTHINFO was part of a proposed NNTP V2
    specification, which was started in 1991 but never completed,
    and is implemented in some servers and clients. It is a
    refinement of the original AUTHINFO and provides the same
    basic functionality, but the sequence of commands is much
    simpler.

    When authorization is required, the server sends a 450 response
    requesting authorization from the client. The client must enter
    AUTHINFO SIMPLE. If the server will accept this form of
    authentication, the server responds with a 350 response. The
    client must then send the username followed by one or more
    space characters followed by the password. If accepted, the
    server returns a 250 response and the client should then
    retry the original command to which the server responded
    with the 450 response. The command should then be processed
    by the server normally. If the combination is not valid,
    the server will return a 452 response.

    Note that the response codes used here were part of the
    proposed NNTP V2 specification and are violations of RFC 977.
    It is recommended that this command not be implemented, but
    use either or both of the other forms of AUTHINFO if such
    functionality if required.

NNTP-Ext 3.1.2.1 Responses

        250 Authorization accepted
        350 Continue with authorization sequence
        450 Authorization required for this command
        452 Authorization rejected