Implementation of Backward Key Chain and Hill Cipher for Securing Messages in the Wireless Sensor Networks

The development of the internet of things (IoT) has been growing, such as wireless sensor networks (WSN). The use of WSN in daily life has helped a lot in various fields. WSN has interconnected nodes with limited memory, resources, and computation. Because of these limitations, messages or data on these nodes are in danger of being tampered with or known by attackers. In this paper, a modification of the broadcast authentication scheme by adding confidentiality to the session key and message is proposed. The session key, produced by a backward key chain, is secured with a modified hill cipher encryption. The experiment results show that the average time required for the hill cipher method for encryption is higher than decryption with a difference of about 0.1579 sec. then the main result of the experiment is the comparison between the ECDH method and the Backward Keychain for both the encryption and decryption process, which results in the Backward Keychain method being better than the ECDH method.