T1 Digital Line Card - 3Com NBX 100 Installation Manual

22 C 1: I
HAPTER NTRODUCTION

T1 Digital Line Card

ANALOG CONNECTORS (Labeled 1 through 4) These connect a
I
local analog line between an NBX 100 and a central office switch.
See "Testing the Installed Hardware" in Chapter 3 for information about
what the LEDs indicate during system startup and operation.
The T1 Digital Line card (Models 3C10116 and 3C10116B) is an optional
card that lets you connect a T1 line to the NBX 100. The system can
accommodate up to 3 Digital Line cards, if you connect them using
MDI-X ports. An external Channel Service Unit (CSU) is required when
using T1 Digital Line cards.
If you connect a Digital Line card using the system backplane, the system
can accommodate only one Digital Line card.
T1 cards can use E&M robbed-bit signaling (sometimes referred to as
Standard T1), or ISDN Primary Rate Interface (PRI) signaling.
By default, the NBX 100 auto discovers a T1 card as T1 E&M, and an E1
card as ISDN PRI.
When configured as standard T1 (E&M robbed-bit signaling), the card
supports inband signaling of 24 DSO (64) Kbps) "voice" channels and a
variety of signaling types and protocols. The T1 carries data at a rate of
1.544 Mbps.
When configured as ISDN PRI, the T1 card supports 23 voice channels
with PRI services such as Automatic Number Identification (ANI).
ISDN PRI services require specific circuit provisioning, which you must
obtain before you can use this card. See Appendix B for more
information.
Figure 4 T1 Digital Line Card (Model 3C10116B Shown)
If you are using the T1 Digital Line card Model 3C10116B, the NBX 100
must be running system software at Release 2.6 or higher. This revision is
a manufacturing change only. It has no effect on quality or functions.