SEPAR: A New Lightweight Hybrid Encryption Algorithm with a Novel Design Approach for IoT

This paper presents a new hybrid encryption algorithm with 16-bit block size and a 128-bit initialization vector, referred to as SEPAR, and it is suitable for IoT devices. The design idea of this algorithm combines pseudorandom permutation and pseudorandom generator functions. This smart integration causes resistance improvement against common cryptographic attacks meanwhile leads to cipher speed increment. Investigation of security analysis on the algorithm and results of the NIST statistical test suit proves its resistance against common cryptographic attacks as linear and differential cryptanalysis. Furthermore, efficient software implementation of SEPAR is presented on 8, 16 and 32-bit platforms. Compared to BORON cipher, SEPAR provides 42.22% throughput improvement on 32-bit ARM CPU. Also, for 8-bit and 16-bit microcontroller, SEPAR provides 87.91% and 98.01% performance improvements compared to present, respectively.