How the DES Algorithm Works

The DES algorithm was widely used following its adoption as the federal encryption standard in 1977. However, it was soon plagued by concerns about my explanation its security and the advent of greater computing power brought new scrutiny to its weaknesses. In the end, DES was sidelined for the more advanced AES algorithm.

DES utilizes a block size of 64 bits to break plaintext down into smaller pieces that are processed by the algorithm over 16 rounds. Each round consists of five different processes. The first step is a permutation, which alters the order of data bits within an area to create fragmented information. Then follows the expansion, key mixing, and another permutation, which creates the encrypted.

Each round also has an XOR operation that utilizes the output of one round as input for the next. This XOR operation blurs the distinction between plaintext (plaintext) and ciphertext (ciphertext) this makes it difficult for attackers to discover the secret key that will generate the proper ciphertext.

The DES algorithm employs S-boxes as well to further disperse the data. This makes it harder for hackers and attackers to discern which bits are plaintext and which are encrypted. In the final phase of each round the text that has been expanded is XORed using a 256-bit key that was generated from the previous round’s key. This provides an additional layer of security against brute force attacks.