Please answer the following question200 words QI would like

Please answer the following question.(200 words)

Q.I would like you to research an encryption type and explain how it works and if it has already been cracked or still uncrack-able. Follow the same flow as last test with the who what when here and how.

Solution

3-KEY Triple DES :

The algorithm was developed in the early 1970s at IBM and based on an earlier design by Horst Feistel. It was submitted to the National Bureau of Standards (NBS).The algorithm is as follows:

The first step is by the user, where he has to generate and distribute a 3TDES key -K . This key consists of 3 different keys namely K1,K2 and K3.Thus , the length would be 3x56=168 bits.

The encryption scheme is illustrated as follows

The encryption process is as follows :

The plaintext block is first encrypted using single DES .This uses the key K1

Then, it is decrypted , ie output of step 1, using single DES with the key K2.

Finally, encrypt the output of step 2 using single DES with key K₃.

The output now obtained from step 3 isconsidered as the ciphertext.

Decryption of a ciphertext is a reverse process.

This is much better than single DES.