AT&T DS1/DMi/ISDN-PRI manual Depending on the particular facility

7-66	ADMINISTRATION OPTIONS AND REQUIREMENTS — GENERIC 2
Field 6	Assigns the interface type or side. The default option is (0) for user side.
	Alternately, a (1) should be administered for network side. The configuration of
	the network should be analyzed to determine whether the (0) option is appropriate.
	For MOS facilities (such as DMI-MOS and ISDN-PRI), each link must be
	segmented into user and network sides. At the Generic 2, each MOS-based facility
	connected to the public network is administered as the user side (0), while the
	network side (such as a 4ESS) is administered (1). For private network DMI-MOS
	and ISDN-PRI connections, additional care must be exercised in defining user and
	network sides. Specifically, only one end must be administered user side (0), while
	the alternate must be defined as the network side (1). If the private network node is
	a tandem switch, then that node may function as both user side and network side
	depending on the particular facility.
	NOTE: Whenever a Generic 2 connects to a host computer via MOS, the
	computer should always be assigned as the network side.
Field 7	This field is used for administering one of four facility test codes. For most
	installations it is desirable to enable or establish permission, thus allowing selected
	maintenance software to test the DMI-MOS/ISDN-PRI transmission facility on a
	demand basis.
	Procedure 648 contains several tests that may be done on a demand basis (by
	executing procedure 648) whenever facility test codes 1, 2, or 3 are administered.
	The DMI-MOS/ISDN-PRI communication protocol consists of three layers or levels.
	Level 1 is the physical layer. Level 2 is the data link layer. Level 3 is the network
	layer, also referred to as the link access procedure on the D channel (LAPD).
	Field encodes and their descriptions are:
	0 Disables or prohibits maintenance testing from being done on the specified
	(module, cabinet, carrier, and slot) transmission facility.

1Assigns that a level-2 test may be executed via procedure 648.

Encode 1 should be translated for all DMI-MOS to host computer links.

2Assigns that only the level-3 network layer may be tested. Level 3 does loopback testing and requires the use of a separate special test line (SN261C).

3Permits both level-2 and level-3 tests to be done.

Encode (3) should be translated for all ISDN-PRI connections that terminate on a 4ESS.

Field 8	This field accepts encodes	from 0 to 126. However, all point-to-point (nonswitched)
	links, such as an System 85 R2V4 or Generic 2 DMI-MOS link to a host computer,
	must be administered with	encode 0 (the default value).