A Survey of Different Public-Key Cryptosystems

Cryptography is the study of techniques which is used to communicate, store in forma tion or data securely, without being intercepted by third parties. In the real world, there are so many organizations working on large databases over a public network. The security of data is the primary concern in the public network. Encryption is the mos t commonly used technique where transactions continuously take p lace between the users. Other cryptography techniques like dig ital time -stamping, dig ital signature, digital certificates etc., are also used for security purpose. In this paper, we have compa red four Public -Key cryptosystem i.e. RSA, Diffie -Hellman Key Exchange, Elgamal Cryptographic System, and Elliptical Curve Cryptography. This paper performs security analysis of the above public key cryptosystem and concluded that ECC is the most efficient public-key cryptosystem. It provides high security solutions that do not impact performance even on constrained devices where storage, computing power and bandwidth are limited such as PDAs and cell phones.