You can create a trunk group that does not have any assigned members. Once a valid port is assigned as a trunk group member, this trunk group then becomes active and may be employed by SLS call processing for incoming/outgoing trunk operation. The slot-configuration table is used, together with the port capacity for the given module, to determine the validity of a port assignment at administration time.

As a result, there may not be more active trunk groups than there are physical trunk members within a given Branch Gateway. In addition, a combo-port may only be used for one active assignment. For example, the analog station/DID trunk ports may be either allocated to serve as an analog station or as an analog DID trunk, but not both.

The maximum limits for a given trunk type are defined by the slot-configuration assignment for the Branch Gateway. The maximum number of ports allowed per interface module is defined in SLS group type assignments.