Introduction to Information Security

Information Security:

In terms of computer information is row facts and figures with processing.

But in contexts of network information is the prescribed message which is sent by particular sender for a specific destination.

Types of Security:

1.     Computer Security:

Computer security is about securing a standalone device.

2.     Network Security:

It is about securing entire network with the network hardware.

Cryptology:

It is the field where the information is hidden.

Cryptography is the combination of branches mathematics and computer science. Basically cryptology is used for the security of ATM cards, computer password and electronic commerce.

Terminology used in Cryptology:

·       Encryption:

Conversion of ordinary information (Plain text) into unintelligible gibberish (Cipher text) is known as Encryption.

·       Decryption:

The reverse process of encryption is known as decryption in which a cipher text should change in plain text.

·       Cipher:

A cipher is a pair of algorithms which creates the encryption and reversing decryption.

·       Secret key:

The unique id or number used in algorithms to make the cipher unbreakable is known as secret key.

·       Cryptanalysis:

The process in which a person or a programmer is trying for capture the original message from a cipher text is known as crypt analysis. And that person is called Cryptanalyst.

Types of Cipher:

Ø Block Cipher:

Block cipher take input as a block of plain text and a key and produces the output a block of cipher text of the same size, since blocks are divided in same size so there should be a knitting mechanism available to combine them.

Note: A common key is used with each block.

Ø Stream Cipher:

It is just contrast to the block cipher for creation of arbitrarily long stream of key material which is combined with the plain text bit by bit or character by character.

Note: Different key is used with each block, and then these blocks are combined in a stream.