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CISA · Question #559

Nonrepudiation services for e-commerce transactions is BEST achieved through which of the following?

The correct answer is C. Public key infrastructure (PKI). Public Key Infrastructure (PKI) best achieves nonrepudiation through the use of digital signatures based on asymmetric cryptography. Because only the sender possesses their private key, a digitally signed transaction proves the sender's identity and prevents them from later…

Submitted by femi9· Apr 18, 2026Protection of Information Assets

Question

Nonrepudiation services for e-commerce transactions is BEST achieved through which of the following?

Options

  • ATransport Layer Security (TLS)
  • BMessage authentication code
  • CPublic key infrastructure (PKI)
  • DData Encryption Standard (DES)

How the community answered

(45 responses)
  • A
    2% (1)
  • B
    7% (3)
  • C
    78% (35)
  • D
    13% (6)

Explanation

Public Key Infrastructure (PKI) best achieves nonrepudiation through the use of digital signatures based on asymmetric cryptography. Because only the sender possesses their private key, a digitally signed transaction proves the sender's identity and prevents them from later denying the transaction. Option A (TLS) provides encryption and authentication in transit but does not create a legally binding proof of origin. Option B (message authentication code) uses a shared symmetric key, so either party could have generated it-meaning either party could repudiate the transaction. Option D (DES) is a symmetric encryption algorithm that provides confidentiality but no nonrepudiation capability.

Topics

#Nonrepudiation#PKI#Digital Signatures#E-commerce Security

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