AT&T DS1/DMi/ISDN-PRI manual V4 Only, DS1/DMI-BOS applications should be administered with a

ADMINISTRATION OPTIONS AND REQUIREMENTS — SYSTEM 85 7-15

Field 15 V4 Only

Some applications require that the contents of the D-channel be inverted to guarantee that the minimum ones-density be maintained. This field shows whether the signaling channel is inverted. Field encodes and their descriptions are:

-(Dash) means ZCS chosen in procedure 260. This is the default when ZCS is chosen (this automatically inverts the D-channel).

The dash is appropriate for all applications of the ANN11_ circuit pack. RBS does not use the 24th-channel to transmit signaling information. 24th-channel signaling via BOS uses A and B bits for signaling, and the channel structure is such that the ones-density is never violated.

0Selects inverted signaling information (contents of the 24th-channel). Either 0 or 1 must be administered for MOS. Recall that B8ZS is recommended for MOS- based applications. However, not all transmission facilities will permit B8ZS on an end-to-end basis. Administration must be coordinated with the network facilities/distant-end to ensure compatibility.

NOTE: This field must be a dash (–)when ZCS line coding is selected with ISDN.

1Selects uninverted signaling information (contents of the 24th-channel). The 1 option (no inversion) is recommended for use when B8ZS is administered.

Field 16	V4 Only
	The DS1/DMI-BOS applications should be administered with a (–).
	The DMI-MOS/ISDN-PRI applications should be optioned (0) for use when
	connecting to metallic copper cable. Connections to fiber cable are not currently
	supported. Therefore, option one is not applicable.
Field 17	V4 Only

This field is added to bring a System 85 R2V4 into compliance with EIA specification PIN-1429. This EIA specification relates to BOS; MOS is defined by a CCITT specification. Field encodes and their descriptions are:

-(Dash) means not applicable. The dash is appropriate for all applications of the ANN35 circuit pack (both DMI-MOS and ISDN-PRI).

0Appropriate for all applications of DS1/DMI-BOS except when connecting to a switch that uses the Canadian style of signaling.

1Selected when connecting to a DS1/DMI-BOS that uses the Canadian style signaling as specified in PN-1429.