Modem Pools; Modem Pools Using System Lines - AT&T MERLIN LEGEND Data Manual

Planning

Modem Pools

See Chapter 1 for information about
connections.
Modem Pools Using System
Lines
3-8
Modem Pools
A modem pool consists of one or more pairs of data modules and modems.
Modem pools convert digital data signals to analog data signals or convert
analog data signals to digital signals and are called "conversion resources."
A modem pool allows data communications between digital data stations and
analog data stations.
An analog-to-digital modem pool is used to call digital data stations from analog
stations. A digital-to-analog modem pool is used to call analog data stations
from digital stations.
A modem pool can use either system lines (shown in Figure 3-1) or dedicated
outside lines (shown in Figure 3-2) and can be either analog to digital or digital
to analog.
Modem pools using dedicated outside lines are useful when
many data calls are made and you want to be sure data lines are kept
separate from outside system lines used for voice calls
your business uses specialized outside lines (such as private circuits for
high-speed transmission) for data communications
Figure 3-1 shows modem pools using system lines. Calls to and from outside
data stations are placed through outside lines connected to the system. These
lines can be reserved for members of a modem pool, or they can be the same
lines that are used for voice communications.
DHG {
012 BASIC
TELEPHONE
STATION
JACKS
DHG {
008 MLX
STATION
JACKS

Modem Pools Using System Lines

Figure 3-1
440A4 = TERMINATING RESISTOR
PSU = WP-90110-L1 POWER UNIT, 115 VAC