R0106-HP MSR Router Series Voice Configuration Guide(V7)

Configuring a logical digital voice interface

The system automatically creates a logical voice interface in the form of E1/T1 interface number:timeslot

set number for a timeslot set.

The description, shutdown, receive gain, transmit gain, and cng-on commands for a logical digital voice

interface have the same functions as those for analog voice interfaces. For more information about those

commands, see related sections in "Configuring analog voice interfaces."

To configure a logical digital voice interface:

Step Command Remarks

1. Enter system view.

system-view N/A

2. Enter logical digital voice

interface view.

subscriber-line

number:ts-set-number

N/A

3. Configure a companding law

for PCM.

pcm { a-law | μ-law }

The default is a-law for logical

digital voice interfaces of E1

interfaces and μ-law for logical

digital voice interfaces of T1

interfaces.

Configuring R2 signaling

ITU-T recommendations Q.400 through Q.490 define the R2 signaling standards. However, the R2

signaling standards implemented in different countries and regions are ITU variants.

In R2 signaling, the calling side serves as the originating PBX, and the called side serves as the

terminating PBX. Signaling sent by the originating PBX is called forward signaling, and signaling sent by

the terminating PBX is called backward signaling, as shown in Figure 15.

Figure 15 R2 signaling elem

ents

R2 signaling include two categories: digital line signaling and interregister signaling. Digital line

signaling conveys status information about E1 trunks to describe whether the trunks are seized, released,

or blocked. Interregister signaling transmits and requests calling and called numbers.

ITU-T digital line signaling

Digital line signaling monitors the state of a trunk and controls calls. It can identify the following state

changes:

• The calling party goes off-hook and seizes the line.

• The called party goes off-hook and answers the call.

• The calling party releases the call.

• The called party releases the call.