Hash functions are used to produce the message digests which are then…
2023
Hash functions are used to produce the message digests which are then encrypted with a private key to get :
- A.
Public key
- B.
Digital signature
- C.
Cipher text
- D.
Data Encryption Standard
Attempted by 248 students.
Show answer & explanation
Correct answer: B
Answer: Digital signature
Explanation:
Step 1: Compute a message digest by applying a hash function to the message.
Step 2: Encrypt the message digest with the sender's private key. The result is the digital signature.
Step 3: Attach the signature to the message and send it.
Step 4 (verification): The recipient computes the hash of the received message, decrypts the signature using the sender's public key to recover the original digest, and compares the two digests. If they match, the message is authentic and unchanged.
Key properties: authentication (confirms the sender), integrity (detects changes), and non-repudiation (sender cannot deny the signature).
Note: The public key is used to verify the signature; ciphertext refers generally to encrypted data, and DES is a symmetric encryption algorithm—none of these terms are the specific result produced by encrypting a message digest with a private key.