Upstream hop-by-hop congestion control in wireless sensor networks

Congestion in wireless sensor networks (WSNs) can lead to packet losses, delay, and energy waste due to a large number of retransmissions and packet drops. It is necessary to carry out congestion control which detects congestion precisely and regulates it fairly. To achieve this objective, an upstream hop-by-hop congestion control (UHCC) protocol based on cross-layer design is proposed. Unlike existing congestion control protocol, the UHCC protocol takes advantage of unoccupied buffer size and traffic rate at MAC layer of each node as congestion level indication, based on which, every upstream traffic rate is adjusted with its node priority (SP) to mitigate congestion hop by hop. Finally, simulation results show that the UHCC protocol achieves higher throughput, better priority-based fairness and lower packet loss ratio than both congestion control and fairness (CCF) and priority-based congestion control (PCCP) protocols.