The Art Of Steganography

INTRODUCTION STEGANOGRAPHY

Steganography is an art of hiding data inside data.Steganography is a form of security technique which is used to hide secret messages in various types of files, including digital images, audio and video. It is very old way of hiding secret data, but it changes a lot with the introduction of new technologies. There are many techniques available today for hiding secret data. For hiding in different cover media, there are different techniques. The main aim of steganography is to hide secret data in an innocently looking cover media. . Detection of presence of data in stego data is known as Steganalysis.

History of Steganography:

Steganography has been used in various forms for 2500 years. Steganography

Public key cryptography is an asymmetric method that use a pair of keys for encryption: a public key which is used to encrypt data, and private, or secret key is used to decryption. It requires that a person must have a pair of public key and private key. The public key is distributed in the open so that anyone wishing to communicate with that in a secure way than he can use the receiver’s public key to convert the plaintext into cipher text. This cipher text cannot be converted into same plaintext using same public key. Therefore, there is no issue if some other person knows about public key. This cipher text is converted into plaintext using receiver’s private key. The Public Key Cryptography can be used to verify the authentication of message in which a message is signed with sender’s private key and it is verified in receiver side by sender’s public key. It also ensures that message has not been tampered, any change in message will result changes in Message Digest, which is a fixed bit string generated from message data. The public key and private key are mathematically related to each other but it is a very difficult job to deduce private key from public key.each other but it is a very difficult job to deduce private key from public

Steganography is often confused with cryptography because the two are similar in the way that they both are used to protect confidential information. The difference between the two is in the output; the output of steganography operation is not apparently visible but in cryptography the output is scrambled so that it can draw attention. Author also defines Steganalysis process to detect of presence of steganography. In this paper they tried to clarify the different methods to implementation of steganography using ‘multimedia’ file like text, image, audio and video as