A Security Key Management Method using Grid Routing for EDDK in WSNs

Wireless sensor networks (WSNs) utilize event data collected through sensor nodes, which can be employed in different environments. Sensor nodes used in WSNs have limited energy and can be easily compromised by attackers since they are placed in the external environment. Therefore, energy efficiency and security are core requirements in WSNs, and various schemes have been proposed to solve them. The energy-efficient distributed deterministic key management scheme (EDDK) is a security scheme that uses distributed pairwise keys. The EDDK encrypts the packet using the pairwise key of the neighboring node, and transmits the encrypted packet securely to the base station (BS). In addition, the pairwise key shared with neighboring nodes is updated to defend against network attacks such as Denial of Service. However, the energies of the sensor nodes decrease rapidly in environments where key updates occur frequently. Further, since EDDK does not encrypt the sequence number, the attacker can manipulate this sequence number. If such attacks are continually attempted, key updates occur frequently. This paper proposes a scheme that removes the local cluster key from the EDDK and instead uses a grid routing protocol. The proposed scheme reduces the number of key updates by removing the local cluster key. In addition, the proposed scheme constructs the routing as a grid and selects the sensor node nearest to the BS as the master node. the master node of the grid routing scheme transmits routing control messages to the corresponding sensor nodes. In this way, the proposed method improves the sensor network energy efficiency. Experimental results show that the energy efficiency of the sensor network is improved by about 7.8097% compared with EDDK. Additionally, since the proposed scheme removes the local cluster key, sequence number manipulation attacks can be avoided. As a result, the security rate of the proposed scheme is more than double compared with EDDK.