Lightweight Data Security Model for IoT Applications: A Dynamic Key Approach

A new symmetric encryption model for enhanced security is designed for the data of any size and type. It is envisaged that the proposed encryption model would enable a range of IoT devices to transfer data or to communicate more securely over open/insecure communication channel and also to provide enhanced data integrity. The model keeps the size of output cipher text unchanged by XORing the parity bits to avoid the overhead and making it lightweight. The chaotic dynamical system was used for key scheming to produce highly sensitive cipher text. Further, the key is dynamically updated using the same parity to increase the reliance of output cipher text on the input plain text. The key with 128-bit length is used for data complexity which is widely known and proven to withstand any kind of brute force attack. Finally, diffusion process was implemented to ensure the effect of any change is retained and carried throughout the process. The simulation results yield average NPCR value to be 99.7113, which demonstrates the potential of the model to be used for IoT based devices and systems where high complexity for data security is required. Different simulation exercises were carried out for change in key, plain text and cipher text and the results are discussed in the paper.