What is the process called when the hash of a document is encrypted with the signer's private key?

What is the process called when the hash of a document is encrypted with the signer's private key?

• A. Hash
• B. Public Key
• C. Encryption
• D. Digital Signature

Answer: (D)

Signing a hash with the signer's private key is a digital signature. The process starts by hashing the document to get a concise digest, then encrypting that digest with the signer's private key to produce the signature. Anyone can verify it by decrypting the signature with the signer’s public key and comparing the result to a fresh hash of the document. This confirms who signed it (authenticity), that the document hasn’t been altered (integrity), and that the signer cannot later deny having signed it (non-repudiation). It’s not about hiding the document’s contents, and the terms hash, public key, or general encryption don’t describe the overall action of creating a verifiable signature.

Signing a hash with the signer's private key is a digital signature. The process starts by hashing the document to get a concise digest, then encrypting that digest with the signer's private key to produce the signature. Anyone can verify it by decrypting the signature with the signer’s public key and comparing the result to a fresh hash of the document. This confirms who signed it (authenticity), that the document hasn’t been altered (integrity), and that the signer cannot later deny having signed it (non-repudiation). It’s not about hiding the document’s contents, and the terms hash, public key, or general encryption don’t describe the overall action of creating a verifiable signature.