DES is a long-standing crypto standard. It is still extensively used. It’s also one of the most researched and understood encryption algorithms, which means that it has been examined for possible weaknesses and vulnerabilities.

The initial step of DES is known as the Initial Permutation (IP). This step takes the input of 64 bits and permutes it according to the predetermined pattern. This changes the ordering of bits, which prevents attacks that employ plaintext known to the attacker.

After the IP the subkeys are divided into two 28 bit subkeys. Each half of the keys is then shifted to the left by an amount of a certain percentage every round. The resulting shifts are then put together using the Permuted Choice 2 (PC-2) algorithm. This produces the round DES keys.

The round keys are XORed together with the ciphertext to generate the final product. This process is repeated 16 times to create the encrypted text. Each round of DES employs a combination of substitute and permutation functions to confuse and confuse the attacker.

The confusion function, one of the S boxes is not nonlinear. This is an important security flaw in DES. It is possible to break DES by using a linear cryptanalysis machine. COPACOBANA, the parallel machine that was built on FPGAs found at the Universities of Bochum in Germany and Kiel in Germany, broke DES within 9 days using the $10,000 hardware. This is an impressive improvement over the previous record for desktop PCs of 6 days, but it’s not enough for security.

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