Reducing Hash Function Complexity: MD5 and SHA-1 as Examples

Hash functions algorithms also called message digest algorithms, compress a message input of an arbitrary length, and produce an output with a fixed length that is distributed randomly. Several hash algorithms exist such as Md5 and SHA1. These algorithms verify data integrity and restrict unauthorized data modification. However, they experience some complexities, especially when implemented in bitcoin mining, and low computation devices, in particularly IoT devices. As a remedy, this paper suggests a new compression function that reduces the complexity of the hash function algorithms such as MD5 and SHA-1. Also, proves that we can obtain the same results which are achieved by the original compression function.