Earners of this badge will be able to describe the benefits of trunked radio systems and define Offered Traffic, Carried Traffic, Blocked Traffic, Grade of Service (GoS), Trunking Gain and the concept of the Erlang. They will understand the distinction between the Erlang-B and Erlang-C traffic models, and how both can be used to determine how many channels will be required, for a given volume of traffic (circuit switched and packet switched), whilst satisfying a specific GoS.