Avaya S8700 Maintenance Manual page 112

Maintenance Object Repair Procedure
Combined Modem Pools
The Combined Modem Pool conversion resource is the second type available.
The function served by the Combined Modem Pool is similar to that of the
integrated Pooled Modem circuit pack, but the physical implementation is much
different. It has the advantage of supporting any speed the external modem can
support. The integrated Pooled Modem circuit pack can only support 300- or
1200-bps transmission rates. The Combined Modem Pool conversion resource
consists of a port on an Analog Line circuit pack, an external modem, a Data
Module, and a port on a TN754 Digital Line circuit pack. The tip and ring interface
of the Analog Line is connected to the modem, the RS-232C interface of the
modem connects to the Data Module, and the DCP interface on the Data Module
is connected to the Digital Line port.
The analog modem signals pass through the Analog Line port to the modem. The
modem converts these to RS-232C signals which are passed on to the Data
Module. The Data Module further converts the signals to the DCP protocol for the
Digital Line port which passes the signals on to the PBX network.
8-808 Issue 1 May 2002 555-233-142