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In Memory of Horst Feistel

How IBM Made The World A Whole Lot More Secure

IBM is a renowned world leader in cryptography, and is developing an amazing platform for trust with their Hyperledger project. The roots of their lead can be traced back to the creation of the Feistel cipher and which implements a symmetric key method.

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Thomas J Watson Research Center — Yorktown Heights
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The Festel cipher

A Feistel cipher essentially uses same encryption and decryption process, and where the key application is just reversed. The basic structure is given below and where we split the input data into blocks. Each block is then split into two (left and right). Each round is then:

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Input text: hello
Key: qwerty
Mode: ecb
==============================
Cipher: 769e845b64e6f7fe
Cipher: dp6EW2Tm9/4=
Plain text: hello
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3-DES

One of the great problems with DES is that its key had been reduced to 56 bits, and which is easily cracked by brute force these days. And so 3-DES was created, and which used two keys (K1 and K2). The encryption process then becomes [here]:

Professor of Cryptography. Serial innovator. Believer in fairness, justice & freedom. EU Citizen. Auld Reekie native. Old World Breaker. New World Creator.

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