A Key-Based Multi-Mode Clock-Controlled Stream Cipher for Real-Time Secure Communications of IoT

Abstract

With the rapid development of the Internet and wireless communications, as well as the popularization of personal communication systems, the security of real-time communications is demanded. The efficient technology of stream ciphers can satisfy this requirement of security. In this paper, to enhance the security strength of stream ciphers, we design a key-based multi-mode clock-controlled stream cipher for real-time secure communications of the Internet of things (IoT). The proposed stream cipher is equipped with a multi-mode depending on the key. The different working modes are shipped with different encrypting circuits depending on the user’s key. We analyze the period, the linear complexity, and use known attacks to verify the security strength of the proposed cipher. Compared with existing dual mode clock-controlled stream ciphers, the merits of our proposed cipher are its long period, high linear complexity, low hardware complex, low initialization clock, and simplicity in mode switching. Furthermore, the proposed cipher passes the FIPS PUB 140-1 and SP800-22 tests, obtaining at least 97.00%.