3Com NBX, Installation Manual

Page: 36 / 248

36 C
HAPTER
1: I
NTRODUCTION
■
Slow, non symmetric blinking pattern — Waiting for the
completion of the binding process to the NCP.
Operation:
■
Off for 9 to 10 seconds, on briefly — Idle, the line is not in use.
■
On for 9 to 10 seconds, off briefly — A telephone call is
connected on this port.
■
Console Connector — This DB-9 connector provides an RS-232
(DCE) TTY terminal connection for maintenance access.
T1 Digital Line Card The optional T1 Digital Line Card lets you connect a T1 line to the NBX
system. When configured as standard T1 (DS1), the T1 card supports
in-band signaling of 24 DS0 (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 Direct Inward Dialing (DID).
You must have an external Channel Service Unit (CSU) when you use the
3C10116C
T1 Digital Line Card. 3C10116D includes an onboard CSU.
The 3C10116D can provide CSU performance statistics, supports
loopback testing, and can be configured as a remote device that
communicates with its NCP over a routed network.
ISDN PRI services require specific circuit provisioning, which you must
obtain before you can use the T1 card in PRI mode. See
Appendix B for
more information.
Figure 10 T1 Digital Line Card (3C10116C)
Figure 11 T1 Digital Line Card (3C10116D)
10BT UPLINK
MDI-X
3C10116C 3Com NBX Digital Line Card
CONSOLE
CF
RA
Nominal
LB
T1