For each DS3 line that the Tmedia or Tdev device will use, a line interface with related line services are configured. The DS3 interface can be configured in a one-to-one relationship with DS3 line services; however, unlike a T1/E1/J1 interface, the DS3 line service can be configured to contain subordinate child line services carrying lower bandwidth payload. A conceptual image is shown below:
Using BITS ports for signaling
Starting with release 2.3 of Toolpack, it is possible to convert unused BITS ports into signaling ports, with indices of 1 and 0 respectively, in order to recover a channel on the primary DS3 connection.