A capacity-aware cross-layer QoS optimization scheme for wireless multimedia networks

A model-based channel capacity prediction scheme is proposed to provide statistical quality-of-service (QoS) guarantees under a medium or high traffic load for IEEE 802.11 based wireless multimedia networks. The proposed scheme perceives the state of wireless link from the MAC retransmission information and calculates the statistical channel capacity especially in saturated traffic load. Based on the capacity prediction model, resource reservation and QoS routing optimization are carried out. Via a cross-layer design approach, the scheme allocates network resource and forwards data packet by taking into consideration of the interference among flows and the link state. Simulation results show that the proposed scheme can achieve more accurate capacity prediction and higher resource utilization than previous QoS routing schemes, and improve network performance in terms of end to end transmission delay, packet delivery ratio and network throughput.