CREST Practitioner Security Analyst (CPSA) Practice

What is AES?

1. An asymmetric encryption standard

2. A block cipher that uses a 128-bit block size

3. A password hashing algorithm

4. A data transmission protocol

The correct answer is: A block cipher that uses a 128-bit block size

AES, which stands for Advanced Encryption Standard, is indeed a block cipher that operates using a fixed block size of 128 bits. This encryption standard is widely recognized and adopted due to its robustness and efficiency in handling data encryption and decryption. AES utilizes key sizes of 128, 192, or 256 bits, providing varying levels of security depending on the application and the sensitivity of the data being protected. The designation of AES as a block cipher indicates that it processes data in fixed-sized blocks, and the choice of 128 bits for the block size is essential for maintaining a balance between security and performance. This structure allows AES to efficiently encrypt large amounts of data while ensuring strong encryption capabilities. Understanding what AES is and how it functions is crucial for security analysts, as it plays a significant role in protecting sensitive information in various applications, from secure communications to data storage.