Cisco Certified Network Associate (CCNA) Practice Exam

What is a binary number generated from original data by applying a mathematical formula called?

1. Encryption Key

2. Hash value

3. Ciphertext

4. Digital Signature

The correct answer is: Hash value

The term describing a binary number created from original data by applying a mathematical formula is known as a hash value. This process involves using a hash function, which takes input data and produces a fixed-size string of characters or a binary number that uniquely represents the original data. Hash values are crucial in various applications, particularly in data integrity verification, because even a small change in the original data will result in a significantly different hash value. Hash functions are commonly used in digital signatures and password storage to ensure that sensitive information remains secure. While the other terms relate to security and data integrity, they have distinct meanings: an encryption key is used to encrypt and decrypt data, ciphertext refers to the encoded output post-encryption, and a digital signature is a verification method that uses a hash in combination with encryption to ensure authenticity and integrity. Understanding the specific roles of these terms helps clarify why "hash value" is the appropriate answer.