High speed circuit switched data over GSM: potential traffic policies

A performance evaluation of the new HSCSD service specified by the ETSI for GSM networks is conducted with the objective of maintaining QoS for the existing voice service. Potential traffic policies to handle this new traffic are investigated. In particular, flexible resource assignment is considered and the notion of effective service time for HSCSD calls introduced. This parameter, proportional to the bandwidth negotiated with the base station, is related to the average achievable bit rate. The effect of channel allocation constraints is also investigated. Delays experienced by HSCSD calls are compared to an optimal transmission operating at the maximum capacity.