Appendix F: Ordering ISDN Without IOCs

Long Distance Service

If facilities are available, subscribe to long distance service sup- porting the bearer capabilities previously listed. Request service supporting circuit-switched 64 kbps or 56 kbps access. It is rec- ommended that the same long distance carrier end-to-end throughout the network to be used.

Deciding What Services to Order

If you are new to ISDN, first obtain the features previously listed. Refer to the section ISDN Service Ordering Information in this appendix as a basic guide. It is easier to begin operating on a full featured line because more options are available. Later, features not actually used can be deleted.

If all of the previous features are not available, compare the actual data service requirements with those which are available. A likely problem is the lack of a clear trunk to provide 64 kbps unre- stricted data service. A solution is to use to 56 kbps service. Sometimes voice circuits are suitable for data service at a reduced bit rate.

5ESS Custom Line Additional Parameters

The AT&T 5ESS central office telephone switch supports a propri- etary ISDN D-channel call control protocol called Custom which is based on CCITT recommendations. The ISU 2x64 configured for switch type AT&T 5ESS will work with lines providing this protocol on 5ESS switches with software version 5E6 or later.

The ISU 2x64 supports the following configurations on 5ESS cus- tom lines:

Point-to-point with one phone number

Multipoint with one phone number

Multipoint with two phone numbers (recommended configu- ration)

The requirements for the 5ESS point-to-point line are defined in

Table F-A.

130

ISU 2x64 Dual Port ISDN Service Unit User Manual

61200051L1-1D

Page 144
Image 144
ADTRAN ISU 2X64 user manual Long Distance Service, Deciding What Services to Order, 5ESS Custom Line Additional Parameters