A Survey of Key Management Schemes for Large Scale Wireless Sensor Networks

Sensor monitoring systems are used in a variety of scenarios, from environment data collection to industrial processing and healthcare. Military activities in hostile areas also depend on these networks, so security is the fundamental mechanism of these networks. To maintain the confidentiality of transmitted data and authentication of node cryptographic techniques, they have an essential requirement of keys. In hashing, encryption and decryption, the importance of keys cannot be overstated. Manage the keys to a vary big number of sensor nodes it a non-trivial task. Key managements include the generate and securely distribute the key to every node. It also includes revoke the keys from compromise nodes in case of any attack and assign the keys to a newly deployed node after an interval. Key refresh after regular interval enhances the network's security and is also the part of key management. Traditional key management technique like diffie hellman and Due to small processing and computing capacity, RSA cannot be used in sensor networks. A single key management may not fulfil all the requirements of an application, so to select the appropriate scheme for an application is also a difficult task. For large sensor networks, a variety of key control schemes have been suggested. We examine state of art key scheme and study the properties of these schemes.