AT&T DS1/DMi/ISDN-PRI manual Dacs, TRANSLATIONS-BASED Problems

B. SAMPLE INSTALLATION AND MAINTENANCE PROBLEMS

Based on field experience, most problems can be categorized into three general areas:

●Translations-based problems

●Synchronization-related problems

●Physical interfacing connection problems

This appendix is organized so that there are additional subject subheadings within each category. The organization is as follows:

Translations-based problems

Facility formats

Trunks and trunk groups

Channel-division multiplexers (CDMs)

Channel-expansion multiplexers (CEMs)

D4-channel banks

Synchronization-related problems

Loss of or no synchronization

Leavenworth loop (timing loop)

D4 synchronization problems

Digital central office (CO) synchronization problems

DACS

Physical interfacing connection problems and recommended solutions

TRANSLATIONS-BASED PROBLEMS

Although these translation problems are primarily related to System 85, the concepts and diagnostic procedures are also applicable to System 75.

The administration of digital signal level 1 (DS1) and digital multiplexed interface (DMI) trunks and trunk groups is similar to that for analog trunks. The same rules for determining trunk type and trunk signaling apply. The differences are that a digital port circuit pack (ANN11_) and the transmission facility characteristics must be translated using procedure 260. Also, procedure 116, rather than procedure 150, is used for assigning the trunk group members to the port locations. These two new procedures and the additional consideration they require make a DS1/DMI a radical departure from analog trunks in terms of:

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