Journal of Communications
In this paper, the authors propose a rank table based routing method to solve congestion and traffic balancing problem in multi-sink ZigBee networks. Each node has a rank table to cache path costs and next hop addresses between itself and all the sinks. All the sinks broadcast heartbeat packets containing their load level information as path costs periodically. Each router adds its own load level to the path cost in the heartbeat packets from sinks before relaying them. The rank table of a node is updated constantly according to the received heartbeats.