THE IMPACT OF PREEMPTIVE PRIORITY IN GPRS ON TCP PERFORMANCE: A MEASUREMENT STUDY
Annika Wennström, Anna Brunström, Juan Rendón, Jan H. Gustafsson · 2004
GPRS extends the widely deployed GSM system with a more effecient wireless Internet access. In this paper we investigate how a TCP transmission over GPRS is affected when it loses all its resources due to preemption by circuit-switched calls with higher priority. The results indicate that TCP performance is degraded more than necessary, as buffered data is flushed immediately when the GPRS traffic is preempted. The time required for error recovery is considerable also for very short preemption periods. The situation would improve if data was buffered during preemption and if the data was transmitted immediately as GPRS resources become available again.