A key management approach for forward and backward secrecy in unattended WSNs

Unattended wireless sensor networks are a different type of wireless sensor network,where sensors operate in hostile environments without a fixed sink to route the sensed data to. alternatively,sensors accumulate and store their sensed data until a mobile sink visits the node and off load them. this situation can lead to breach of data privacy,when,upon a node compromise,an adversary can access the stored data and any encryption keys the node possesses. therefore,it is essential to ensure the secrecy of data,which was generated before capture,termed forward secrecy,as well as secrecy of data generated after the node has been compromised,termed backward secrecy. in this work,we present a distributed scheme that utilizes key evolution to ensure forward secrecy,and uses a co-operative data distribution mechanism to ensure backward secrecy of the sensor node's data.