Introduction
Packet network
- statistical sharing of network resources
- packets delayed or dropped during congestion
Traditional congestion control technique
- end system dynamically measures available bandwidth
- adapts to network congestion
- works only if all sources comply
- cannot provide differential or guaranteed QoS
QoS approaches today
- end-to-end delay or bandwidth guarantee on a per flow basis
- different QoS classes: guaranteed, statistical, predicted, controlled load, differential