In the age of information, security issues play a crucial role. Security comes with three points’ confidentiality, integrity and availability. The entire above said thing will come from an efficient cryptographic algorithm. We need special hardware to implement these cryptographic algorithms to provide higher throughput. This hardware should have high flexibility since the cryptographic algorithms are constantly changing. To achieve this goal VLSI implementation of these cryptosystem is the best solution. Our work is mainly based on designing architectures for Rivest–Shamir–Adleman (RSA), one of the most well-known public key cryptosystem. This work started with the understanding of basics of cryptography and modular arithmetic which is essential to understand cryptographic algorithm. Then in the cryptographic module RSA, a public key cryptographic module is chosen as the algorithm for implementation. The design goal is to increase the speed or in other words the throughput of RSA cryptosystem
