Maintenance Modem Line; Cabling - Avaya CS700 Administration And Maintenance

Site Requirements

Maintenance Modem Line

A phone line must be dedicated to the external maintenance modem. Use a POTS loop-start
line. The maintenance modem enables technical support personnel to dial directly into the
system to provide remote support such as running diagnostics, troubleshooting, or updating
software.

Cabling

Cabling is shielded twisted pair (1 pair transmit, 1 pair receive). Avaya recommends use of
Category 5 cable. The shield is not terminated at the digital system. If the cable is continuous to
the PBX or channel bank, the shield must be grounded to frame ground at that end. If there is a
DSX or other break in the cable, the shield must be connected to the shield of the other cable.
A CSU can be used to drive signals greater distances.
Note:
A CSU is required for customer premise connection to public telephone networks.
Note:
Tip:
The local phone company can recommend a CSU.
Tip:
There are many kinds of CSUs available, and the CSU you select must include:
Remote loopbacks for testing repeated T1 lines from the CO.
l
Terminating T1 repeater power (up to +/-130 Vdc).
l
Alarming.
l
Provision for an all 1s signal to the T1 lines, if the conference system is serviced. (Also
l
called blue or keep alive signal.)
When connecting a system to more than one telephone network, keep the following in mind:
The system synchronizes to the first T1.
l
Because there may be large accumulated jitter at the end points of two T1 networks, the
l
CSU requires large buffers to attenuate such jitter.
Without adequate jitter attenuation, excessive frame slips occur.
l
322 Administration and Maintenance of the CS700/CS780 Audio Conferencing Server