Similar questions

1) Compare Cryptography and Steganography.

2) Explain the Steganography with example. Distinguish between steganography and cryptography

Cryptography:

1. An orginal message is known as plain text, while the coded message is known as “Ciphertext”.
2. The process of converting plain text to ciphertext is known as ciphering or encryption , restoring the main text from ciphertext is known as deciphering or decryption.
3. The various schemes used for encryption are known as ‘Cryptography’ and the system is used to known as ‘Cryptographic System’.
4. Techniques used for deciphering a message without any knowledge of ciphering details is known as “Crypto- Analysis” (Breaking the Code)
5. The area of Cryptography and Crypto Analysis together is called as “ Cryptology”.

$$\text{Figure 4.13 Model of Conventional Encryption}$$

Steganography:

1. The method of cryptography sender the message unintelligible to outsiders by various transformations of the text.
2. The method of Steganography conceal the existence of message.

3. The various techniques used are:

   A. Character Marking: Selected letters are overwritten in pencil. The marks are ordinarily not visible unless the paper is held at an angle to bright light.

   B. Invisible Ink: A number of substances can be used for writing but secure trace until some other chemical is applied to the paper.

   C. Pin Punctures: Small pin punctures on the pictures are ordinarily not visible unless the paper is held up in front of a light.

   D. Subset Method: In this method subset of the words of the overall message is used to convey the hidden message.

4. Disadvantages/ Drawbacks compared to Encryption:

   • It requires a lot of overhead to hide a relatively few bits of information.
   • Once the system is discovered it becomes totally useless.

5. Alternatively a message can be encrypted and then hidden using steganography.