Investigating the Effects of varying the Key Size on the Performance of AES Algorithm for Encryption of Data over a Communication Channel

Abstract

Key size of an algorithm is an important aspect of cryptographic technique as high key bits is considered more secure than low key bits. Different research work has been conducted to have secure and reliable protection techniques for transmitting data over a communication networks. This paper shows the effects of varying the key size on Advanced Encryption Standard (AES) algorithm for encryption of data. AES algorithm with key sizes of 128 bits, 192 bits and 256 bits were considered. The performance of the system were examined based on the encryption and decryption time, throughput, average data rate and the central processing units (CPU) power consumption. Consequently, AES with key size of 128 bits has a lower encryption time, higher throughput and low CPU power consumption than AES with 192 bits and 256 bits keys.