A rate-allocation based multi-path congestion control scheme for event-driven wireless sensor networks on constant event packet rates

摘要

In this paper, we proposed a rate-allocation based multi-path congestion control approach, called multi-path-congestion control method (MUCON for short), which enforcing high path availability of packet delivery for event-driven Wireless Sensor Networks (WSNs) consists of two parts. The first is constructing a spanning tree to connect all sensor nodes of a WSN to the sink for initial routing. The second is establishing a fair packet forwarding environment by employing multi-path and rate control to deliver packets through routing paths with a balanced manner. Generally, the occurrence of an event will increase net flow, which may congest the nodes on the newly established routing path if the nodes are currently shared by several routing paths, particularly for those nodes near the sink, consequently ruining originally balanced traffic on paths and forcing some event packets to be dropped. In fact, without the information conveyed on the lost packets, users may make an inaccurate decision and react improperly for events. When an event disappears, the surrounding sensor(s) stops transmitting packets. This will again destroy the fairness and unbalance net flows flowing through the co-node routing paths. Thus, to maintain the fairness and balance net flows for a WSN, a downstream node needs to dynamically adjust bandwidths for all its upstream nodes. Experimental results show that this method can effectively improve a WSN' throughputs, shorter end-to-end delays and reduce packet loss rates.