ADTRAN 1200051L6 - Manual (Page 18)

Chapter 1.Understanding ISDN and the ISU 2x64
4 ISU 2x64 Dual Port ISDN Service Unit User Manual 61200051L1-1D
Figure 1-2
ISU 2x64 Front Panel
ISU 2X64 INTEROPERABILITY
Telephone networks are evolving from analog technologies to
digital technologies such as ISDN. This transition is time-consum-
ing and costly for the telephone companies and upgrading all lo-
cations and facilities is a lengthy process.
The ISU 2x64 bridges this transition by supporting communica-
tions with existing and future network services and equipment.
The ISU 2x64 supports communications with Switched 56 Service
and Switched 56 DSUs (2-wire and 4-wire) as well as various
ISDN terminal adapters, ISDN terminal equipment, and BOND-
ING-compatible Inverse Multiplexers.
Figure 1-3 illustrates the ISU 2x64 operation in various switched
network services and customer premises products.
ISU 2X64 SINGLE PORT OPERATION
The ADTRAN ISU 2x64 is designed to operate over multipoint
ISDN lines in North America that will require two Service Profile
Identification (SPID) numbers from the telephone company when
the ISDN lines are installed. These SPID numbers tell the ADT-
RAN ISU 2x64 which port or DTE# to route incoming and outgo-
ing calls. See
Ordering ISDN Without IOCs on page 125 for further
details on ordering multipoint ISDN service.
ENTER 1 2 3
4 5 6
7 8 9
# 0 * CANCEL
R S C S T D R D C D T R S R
ISU 2X64