Cisco Cyber Security Practice Exam

Which cryptographic process ensures the authenticity and integrity of a transmitted message?

1. Compression

2. Encryption

3. Hashing

4. Encoding

The correct answer is: Hashing

Hashing is a cryptographic process that ensures the authenticity and integrity of a transmitted message by transforming the original message into a fixed-length string of characters, which is unique to that specific input. This process generates a hash value that represents the content of the message. When the message is transmitted, the sender generates a hash of both the original message and sends it along with the message itself. Upon receipt, the receiver can independently generate a hash from the received message and compare it to the hash sent. If the hash values match, it verifies that the message has not been altered in transit, ensuring data integrity. Hashing also contributes to authenticity because if the hash is generated using a secret key (as in HMAC, for example), it provides assurance that the message has come from a legitimate sender who possesses the same secret key. The other processes listed, such as compression, encryption, and encoding, serve different purposes. Compression reduces the size of data, encryption secures data to prevent unauthorized access, and encoding transforms data into a different format for transmission. None of these processes inherently provide the same level of assurance regarding authenticity and integrity as hashing does.