What does non-repudiation provide to the sender and the recipient of information?

• A. Proof of message integrity
• B. Proof of delivery and sender’s identity
• C. Access to encrypted resources
• D. Assurance of data privacy

Answer: (B)

Non-repudiation is a crucial aspect of information security that provides both the sender and the recipient with undeniable proof regarding the authenticity of a communication. This means that the sender cannot deny sending the message, and the recipient cannot deny receiving it.

The correct answer reflects two key components of non-repudiation: proof of delivery and verification of the sender's identity. When a message is transmitted with non-repudiation measures in place, mechanisms such as digital signatures and secure delivery receipts ensure that the communication is verifiable. The sender cannot later claim that they did not send the message, and similarly, the recipient can demonstrate that they received the message. This is fundamental in scenarios where accountability is critical, such as in legal or financial communications.

Other options fail to capture the essence of non-repudiation effectively. While proof of message integrity is important for ensuring that the content has not been altered (and thus relates more to message integrity rather than non-repudiation), access to encrypted resources focuses on confidentiality rather than the accountability of communication. Lastly, assurance of data privacy addresses the protection of information from unauthorized access but does not involve the aspects of identity verification and message delivery that characterize non-repudiation.