Creates an X.25 access reachable address entity which maps a
    destination network service access point (NSAP) address in an
    outgoing call to a DTE class/DTE address pair.

    create [node node-id] x25 access -
            reachable address address-name -
            address prefix address-prefix

    The Address Prefix argument is required.  It is the leading
    substring of an NSAP address associated with this reachable
    address entity.

    Example:

    create x25 access reachable address x121 address prefix 37