Which of the following keys did Louis use to verify the digital signature in the above scenario?

Riley sent a secret message to Louis. Before sending the message, Riley digitally signed the message using his private key. Louis received the message, verified the digital signature using the corresponding key to ensure that the message was not tampered during transit.

Which of the following keys did Louis use to verify the digital signature in the above scenario?
A . Riley’s public key
B . Louis’s public key
C . Riley’s private key
D . Louis’s private key

View Answer

Answer: A

Explanation:

Riley’s public key is the key that Louis used to verify the digital signature in the above scenario. A digital signature is a cryptographic technique that verifies the authenticity and integrity of a message or document. A digital signature is created by applying a hash function to the message or document and then encrypting the hash value with the sender’s private key. A digital signature can be verified by decrypting the hash value with the sender’s public key and comparing it with the hash value of the original message or document. Riley’s public key is the key that corresponds to Riley’s private key, which he used to sign the message. Louis’s public key is the key that corresponds to Louis’s private key, which he may use to encrypt or decrypt messages with Riley. Louis’s private key is the key that only Louis knows and can use to sign or decrypt messages. Riley’s private key is the key that only Riley knows and can use to sign or encrypt messages.