Abstract: The uses of computer & communication systems by industry has increased day by day and the theft of proprietary information is also increased. For protecting those information encryption is a primary method which is used for protecting valuable electronic information now a days by the industry and military department. Cryptography is the most important aspect of communication and network security. Cryptography is encryption and decryption of the information which is transferred through internet and even more than this. Authentication is a part of privacy which provides the unique identity to the sender and receiver too. We use authentication in everyday lives - when we sign our name to some documents it shows that itís a valid document for this we need to have electronic techniques for providing authentication. A digital signature is also works like authentication in which sender needs to use his own digital signature which show that the information is send by the authorized sender. These cryptographic mechanisms can be used to control access to a shared disk drive, a high security installation. The problem of providing the security to the electronic information and electronic business transaction are became critical so for securing this data we are using all the above techniques: Symmetric Encryption Algorithm, Asymmetric Encryption Algorithm and many more.

Keywords: RSA- Rivest-Shamir-Adleman, DS- Digital signature, DES- Data Encryption Standard, 3DES- Triple Data Encryption Standard, AES-Advanced Encryption Standards, IDES- International Data Encryption Standard, Encryption, Decryption, Cryptography.