Aiming at characteristics of constrained resource and difficulty of network maintenance and software updates of wireless sensor networks（ WSNs）

design a node software update method that meets the characteristics and applications of WSNs

use Contiki operating system as development platform. By means of continuous allocation and memory moving based on relocation information

design a strategy of high utilization rate for memory use

based on Blackboard model management method

achieve lifecycle management of registration

update and uninstall of service module. Experimental results show that size and update time of update module are reduced by15 % and 13 % respectively

and the entire system design improves energy and memory efficiency of sensor node and extends node life.