Library /sys$common/syshlp/ncphelp.hlb SET, LINE, PROTOCOL protocol-name  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Specifies the Data Link protocol to be used on this line.  The
 following values can be used for protocol-name:

 DDCMP CONTROL    Specifies this line as a multipoint control station.
                  You can specify multiple circuits for CONTROL lines,
                  but each circuit must have a unique physical
                  tributary address.

 DDCMP DMC        Specifies that this line is in DMC emulator mode.
                  DMC is similar to POINT, except that DMC uses an
                  older version of DDCMP (Version 3.2).  This protocol
                  should be set for the local line when the remote
                  line is a DMC.  Note that this protocol is valid
                  only when a DMP11 or DMV11 is being used.

 DDCMP POINT      Specifies this line as one of a point-to-point DDCMP
                  connection.  You can specify only one circuit per
                  POINT line.

 DDCMP TRIBUTARY  Specifies that this line is a tributary end of a
                  DDCMP multipoint group.  You may specify only one
                  circuit per TRIBUTARY line.

 ETHERNET         Specifies that this line uses the Ethernet protocol.

 FDDI             Specifies that this line uses the FDDI protocol.

 LAPB             Specifies that this line uses the X.25 level 2
                  protocol.  The line must be a line for the
                  X25-PROTOCOL module.

 LAPBE            Specifies that this line uses the X.25 level 2
                  protocol with extended sequencing.  The line must be
                  used by the X25-PROTOCOL module.

 Default line protocols are based on line names.  See HELP PARAMETERS
 DEVICE-TYPE for a list of circuit and line devices.