Cryptography is an excellent art/science of protecting data from unwanted intruders by transforming the data to an unreadable format which can be brought back to the original form only by those who are authenticated to do so. This system depends vastly on a principle of key usage and is the basic underlying principle of network security. A detailed technical discussion of cryptography ,particularly from a network’s stand point provides a compelling and an up to date examination of the political and the social issues that are now inextricably intertwined with cryptography. A complete discussion of cryptography itself requires a complete book and so we touch on only the essential aspects of cryptography. It is now high time to introduce Alice and Bob who are essentially the widely accepted persons for a discussion on networks as communicators. Also ,the third party Trudy ,the intruder also has a wide role to play in hacking the discussion of the two. So the whole thread would hang about these three and the ways there adhere to secure and hack the data that is transmitted.
A First look on Terminologies
Now its high time to know the basic terminologies of Cryptography. Firstly the text that we type in the human understandable format is called as the Plain Text. The plain text is then converted to a generally incomprehensive form called as the Cipher text using a technique called Encryption which usually does this, and the cipher is transmitted. Precisely a particular encoding way is chosen by a series of letters or numbers for the encryption and the decryption called as the Key. The cipher when reaches the receiver is converted back to the plain text form by the usage of a key and the technique called as Decryption or Deciphering. Ciphering and deciphering follow specified formats making them a privilege to be used by the definitions of…...