Now, you must create a new line service, for your line interface. A line service defines the payload type of a line interface or another line service. The line service chain stops when it reach the E1/J1/T1 line service.
The E1/J1/T1 line services are also known as trunks or spans.
To create a new line service:
1- Select Tdm Interfaces-->Line Interfaces from the navigation panel
2- Click Edit next to the line service for which you wish to create a line service
3- In the following window, click Create New Child Line Service (also, a number can be created at once by selecting Create Multiple Child Line Service)
4- Create the new Child Line Service:
- Enter a name for the new line
- Select an available local index, from the drop-down box
- Select appropriate framing and loopback modes
- Click Create
5- Navigate back to the line interface page, by following link displayed in the upper-left corner of the screen. The new line service should be displayed in the Line Services list