Technical information

Chapter 2 - Technical Information

Indicators on the PRI Network Interface Module

The tables below describe the expected behavior of the indicator

lamps on the PRI network interface module. On the network side,

the expected behavior depends on whether it is a T1 module or an

E1 module.

Non-Facility

Associated Signaling

(NFAS)

Not supported

Special services

(Caller ID, call

blocking, etc.)

Not supported

Table 2-17. PRI Network Side Indicator Lamps

Indication PRI T1 PRI E1

Red LED blinking Not connected to the network, or no power to the

upstream equipment

Red LED on Connected to the network, but no clock sync

Yellow LED blinking Receiving clock and

frame sync; receiving

RAI from the network

with CRC errors

Yellow LED on Receiving clock and

frame sync, waiting for

a timer to elapse

Receiving clock and

frame sync; receiving

Remote Alarm

Indication (RAI) from

the network with no

Cyclic Redundancy

Check (CRC) errors

Red and yellow

LEDs on

Receiving clock sync;

receiving AIS Alarm

Indication Signal

(unframed all-ones)

Green LED on Synchronized with the network and ready to use

Table 2-16. PRI T1 and E1 Network Interface Modules (Continued)

Parameter PRI T1 PRI E1