  Through the years, the flow of Data and its transmission have increased
tremendously and so has the security issues to it. Cryptography in recent years
with the advancement of VLSI has led to its implementation of Encryption and
Decryption techniques, where the process of translating and converting
plaintext into cypher text and vice versa is made possible. In this paper, the
review of various aspects of VLSI's implementation of encryption and decryption
are covered. To systemize the material, the information about topics such as
Private Key Encryption, Index Technique, Blowfish Algorithm, DNA cryptography,
and many more are reviewed. Ultimately, with this review, the basic
understanding of different VLSI techniques of Encryption and Decryption can be
studied and implemented.
