Extended hierarchical routing protocol in 6LoWPAN networks

6LoWPAN enables the IPv6 communication over IEEE 802.15.4 Low-rate Wireless Personal Area Networks(LoWPAN) .HiLow is a mesh-under based hierarchical routing protocol in 6LoWPAN networks,which reduces the memory requirement and the number of control packages,but there are still problems such as lacking routing recovery.This paper describes three problems and suggests a mechanism for routing recovery and a strategy of choosing coordinator and parent node.An implementation of this hierarchical routing protocol is programmed in NS2 and the simulation result shows that the mechanism works well.