Cryptographic Tools and Security

<p>Symmetric encryption</p> Signup and view all the answers

<p>Use of a 56-bit key</p> Signup and view all the answers

<p>Potential weaknesses of symmetric encryption include reliance on the nature of the algorithm and some knowledge of plaintext characteristics, as well as the possibility of brute-force attacks. Attackers exploit these weaknesses through cryptanalysis, which involves deducing specific plaintext or keys by exploiting characteristics of the algorithm, or by attempting exhaustive key searches.</p> Signup and view all the answers

<p>DES uses a 64-bit plaintext block and a 56-bit key to produce a 64-bit ciphertext block, while Triple-DES repeats the basic DES algorithm three times using either two or three unique keys. Triple-DES is considered much more secure but also slower compared to DES.</p> Signup and view all the answers

<p>NIST considered efficiency, security, hardware/software suitability, and the key lengths of 128, 192, and 256 bits when selecting the Advanced Encryption Standard (AES) in 2001.</p> Signup and view all the answers

<p>Message Authentication protects against active attacks by verifying that the received message is authentic and unaltered from the authentic source and is timely and in the correct sequence. The key requirements for Message Authentication Codes include the ability to be applied to any size data and to produce a fixed-length output.</p> Signup and view all the answers

<p>Rijndael was selected for its efficiency, security, and suitability for both hardware and software implementations. It uses 128-bit data and supports key lengths of 128, 192, and 256 bits, making it widely available commercially as the chosen symmetric block cipher for AES.</p> Signup and view all the answers