Abstract: A communication system, in particular a fixed wireless access communication system, including a transmission link, such as a broadcast downlink or a multiple access uplink, having a number of channels and apparatus for transmitting circuit switched and packet switched traffic over said transmission link. The system additionally includes a controller device for periodically pre-allocating channels to circuit switched traffic for a set time period dependent on one or more system parameters existing in a previous set time period. The system parameter may be the number of circuit switched connections operating in a previous set time period. The controller device may comprise a monitoring unit for determining a first number equal to the number of operating circuit switched connections in a previous set time period, a summing unit for forming a sum of the first number and an estimated margin and apparatus for allocating the summed number of channels to circuit switched connections for the next set time period.