Why is a digital signature used to provide the authenticity of digitally signed data?
- Both the signer and the recipient must first agree on a shared secret key that is only known to both parties.
- Both the signer and the recipient must first agree on the public/private key pair that is only known to both parties.
- Only the signer has sole possession of the private key.
- Only the recipient has a copy of the private key to decrypt the signature
| Explanation & Hint:
A digital signature is used to provide the authenticity of digitally signed data because:
In a digital signature, the signer uses their unique private key to sign the data, creating a digital signature. This signature can then be verified by anyone who has access to the signer’s corresponding public key. The fact that only the signer knows the private key ensures that the data was indeed signed by them, providing authenticity. Additionally, any changes to the data after signing would invalidate the signature, which also ensures data integrity. The recipient does not need a private key to verify the signature; they only need the signer’s public key. |