An Improved IDEA Algorithm Based on USB Security Key

Since the IDEA algorithm has the advantage of resisting difference analysis and correlation analysis, its work pattern of random feedback is applied to USB security key to improve the system security. By distributing key based on grouping by sum checkout and using low-high-bit method to simplify the modular exponentiation, it can improve operation efficiency of IDEA algorithm. Experiments show that this algorithm can present better performance for diffusivity.