Avaya 03-300430 User Manual

The TN2185 circuit pack contains eight, 4-wire ports that interface to the network at the ISDN S/
T reference point over two 64-kbps channels (B1 and B2) and over a 16-kbps signaling (D) 
channel.

Note:

 / 

: Although the TBRI-TRK MO is provided for a G700 media gateway, 

this MO only partially supports the G700’s MM720 BRI media module.

The B1 and B2 channels can be simultaneously circuit-switched, or individually 
packet-switched. Only one channel per trunk can be packet-switched due to PPE (Packet 
Processing Element) limitations. The D channel is either circuit- or packet-switched. Packet 
switching uses the PPE to combine all D channels into a single physical channel, which is then 
routed via the concentration highway to the NCE (Network Control Element) and then to the 
TDM bus. The circuit-switched connections have a Mu-law or A-law option for voice and 
operate as 64-kbps clear data channels. The packet-switched channels support the LAPD 
protocol and conform with the CCITT Q.920 Recommendations for D-channel signaling.

The three LEDs on the circuit pack’s faceplate indicate board status. When illuminated, the red 
LED indicates a board failure or a major or minor on-board alarm, the green LED indicates that 
testing is in progress, and the amber LED indicates that the board is in use.

TBRI-TRK

1

1. For additional repair information, also see 

on page 2200 maintenance documentation.

MAJ

2

2. A MAJOR alarm on a trunk indicates that alarms on these trunks are not downgraded by set options 

and that at least 75 percent of the trunks in this trunk group are alarmed.

test trunk location l

Trunk-Side ISDN BRI Channel

TBRI-TRK

MIN

test trunk location l

Trunk-Side ISDN BRI Channel

TBRI-TRK

WRN

test trunk location sh

Trunk-Side ISDN BRI Channel