Network Defense Essentials (NDE) Practice Exam 2025 - Free Network Defense Practice Questions and Study Guide

The principle that ensures a sender cannot deny sending a message is nonrepudiation. Nonrepudiation is crucial in cybersecurity and digital communications because it provides proof of the origin of the message. It combines methods such as digital signatures, which bind the sender’s identity to the message. This means that once the message is sent and signed, the sender cannot later claim that they did not send it.

This principle is essential in various scenarios, including legal contexts, where it may be necessary to prove that a specific individual transmitted a particular communication. By implementing nonrepudiation measures, organizations can maintain trust in their communications and can hold parties accountable for their actions in communication exchanges.

The other principles, while relevant to the broader context of network security, focus on different aspects. Accountability relates to keeping track of user actions in a system; integrity ensures that data remains accurate and unaltered; and confidentiality ensures that information is only accessible to those authorized to see it. However, none of these address the specific issue of a sender denying their involvement in sending a communication as effectively as nonrepudiation does.