摘要：In this paper, we propose a congestion avoidance policy to extend lifetime of sensor networks and to avoid congestion in advance. After proposed policy estimates states of congestion based on arrival rate of packets and throughput of a sensor node, controls sending rate of sensor nodes that sent packets. Proposed policy consists of congestion monitoring state, congestion avoidance state and congestion enable state according to degree of congestion. In addition, sensor nodes can be controlled their sending rates by a selective rate control scheme, a differential rate control scheme and a initial rate control scheme. Each scheme is executed by each the three schemes. In the selective rate control scheme and the differential rate control scheme, sending rate is controlled proportionally to transmission distance of sensor nodes to reduce their energy consumption caused by re-transmission. In the rate of dropped packets and energy consumption, proposed policy shows superior to compared policy.
关键词：Sensor Network; Congestion Control; Congestion Avoidance; Energy Consumption
