The Design of a Key Expansion Algorithm Based on Dynamic Dislocation Counts

With the development of the wireless sensor networks (WSNs), the security is becoming more and more serious. The key schedules in lightweight block ciphers are often highly simplified, which causes loopholes that could be exploited in many attacks. The research on key expansion has become one of the pivotal technologies which aimed at improving performances of the encryption algorithms to solve the issue on how to guarantee enough safety and diffusion of secret key with limited resources and operations. After lucubrating and analyzing the commonly methods, a new key expansion algorithm based on the dynamic dislocation counts is proposed. The data from the simulation and verification show that the method can achieve the expansion of the key effectively and it has a good randomness. It can also be extended to the plaintext to increase the random diversity.