Implementation of hybrid cryptosystem using Rabin-p algorithm and One Time Pad to secure images

Abstract

Cryptography is a study of mathematical techniques to secure messages by encoding the messages so it cannot be read by a third party. There are two types of algorithms in cryptography, symmetric algorithm and asymmetric algorithm. Asymmetric algorithms, such as Rabin-p cryptosystem, are known to be secure if the key sizes are long enough. However, asymmetric algorithms are ineffective to encrypt large data since the calculations consume CPU time and the resulting ciphertext is multiple times bigger than the original data. In this research, we combine Rabin-p cryptosystem and One Time Pad (OTP) in a hybrid scheme to solve this problem. The OTP is used to encrypt the data (images) and Rabin-p algorithm is used to encrypt the OTP key. In this research, we demonstrate how to secure a *.bmp file with this hybrid scheme.