Using priority, buffering, threshold control, and reservation techniques to improve channel-allocation schemes for the GPRS system

Taking a comprehensive approach, we investigate effects on the channel allocation for the general packet radio service (GPRS) system caused by priority strategy, buffering, threshold control on the buffer, and channel reservation. Moreover, four new dynamic channel-allocation schemes based on various combinations of these techniques are proposed and analyzed using the Markov chain approach. Analytical results obtained include blocking/forced-termination/dropping probabilities, cost-function definition based on the above metrics, and (mean) delay times. Through numerical examples, we demonstrate that: 1) priority and threshold control are efficient strategies to differentiate the quality of service (QoS) between a new voice call and a handoff voice call; 2) buffering allows more admitted rates of voice calls or data packets, but increases the delay time; and 3) channel reservation may directly improve a specific service, but it degrades performance of other services much. At last, better schemes suitable for the GPRS system are suggested after a thorough comparison of system performance.