Day after day, the digital data sizes undergo rapid increases over Internet, it is significant; the data shouldn’t be accessed by the unauthorized users. The attackers attempt at accessing those sensitive part of the data. There is a necessity for the prevention of the unauthorized access of the data and guarantee the secure data exchange. A variety of the cryptographic approaches have been used for the conversion of the secret data of the users into secure ciphertext formats. The cryptographic methods have been based on, private and public keys. The researchers have worked on the efficient and secure transmission of data and presented a variety of the cryptographic approaches. For the efficient and secure transmission of the data over networks, there is a necessity of using hybrid approaches of encryption. In this article, various encryption methods are reviewed such as Rijndael, Number Theory Research Unit, Data Encryption Standard, 3 Data Encryption Standard, Elliptic Curve Cryptography, Rivest–Shamir–Adleman, Optimal Asymmetric Encryption Padding, Diffie-Hellman, HiSea, Improved Caesar, Digital Signature, and Advance Encryption Standard.
Keywords: Brute Force Attack, Cryptography, Digital Data, Hybrid Encryption, Search Space.