Library /sys$common/syshlp/nclhelp.hlb set, session_control, incoming_timer  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Default: 45            Values: 0-65535

    Time (in seconds) to wait for a user module to issue an
    accept/reject call after a port enters a state indicating that
    a connection request was received. If the timer expires, Session
    Control aborts the transport connection with a timed out error.
    For OpenVMS, a zero (0) value directs Session Control to wait
    indefinitely without aborting the connection.

    Example:

    set session control incoming timer 45