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

    Default: Off           Value: On or Off

    Specifies whether the value of the characteristic local station
    address is to be interpreted as a valid address. This attribute
    is supported only if the characteristic protocol is set to
    sdlc. You can modify this characteristic only when the entity
    is disabled.