AT&T DS1/DMi/ISDN-PRI manual Field

	ADMINISTRATION OPTIONS AND REQUIREMENTS — GENERIC 2	7-81
Field 3	All endpoints (such as analog lines and DCP voice terminals) must show their
	information transfer requirements in terms of a BC code. The BC code is the
	mechanism by which specialized routing is provided for various categories of calls.

NOTE: Once the BC code is assigned, it is fixed and does not change with different calls.

Field encodes and their descriptions are:

	0	Voice and Voice-grade data
	1	Mode 1	data (56K-bps)
	2 Mode 2		data (subrate up to 19.2K-bps)
	3	Mode 3	data (also called packet mode)
	4	Mode 0	data (64K-bps digital data)
Field 4	This field shows the ISDN-PRI routing option. Field encodes and their descriptions
	are:

0Any type of trunking facility is OK. The 0 option should be used when there are no specific requirements for ISDN-PRI trunks. Generally, this will include all voice and voice-grade data applications (BC code = 0) except those where user- to-user information transfer is desired.

1ISDN-PRI trunking facilities are required. Generally, these applications include those COS groups established for Mode 1 data (BC code = 1), Mode 3 data (BC code = 3), and Mode 0 data (BC code = 4).

NOTE: Mode 0 data, depending on its origin, may require a restricted channel. Recall that an unrestricted channel is only provided by those ISDN-PRI facilities that use the B8ZS line-coding format.

2Any trunking facility will work but ISDN-PRI trunk facilities are preferred. This may include voice and voice-grade data (BC code = 0) and Mode 2 data (BC code = 2).

Procedure 100 Word 1: Trunk Group Type Signaling and Dial Access (ID) Code

Translating Word 1 is the first step in establishing trunk groups. Those trunk groups established for ISDN applications may be of the same design as those for non-ISDN applications, except for the type of signaling used. Or, they may (optionally) be designed to take maximum advantage of the ISDN capabilities. Figure 7-39,Procedure 100 Word 1: Trunk Group Type Signaling and Dial access (ID) Code, depicts this procedure.