Certified Incident Handler (CIH) Practice Ecam

What element of information security ensures that a sender cannot deny sending a message?

1. Availability

2. Integrity

3. Non-repudiation

4. Authenticity

The correct answer is: Non-repudiation

The element of information security that ensures a sender cannot deny sending a message is non-repudiation. Non-repudiation provides proof of the origin, delivery, and receipt of data, which is essential in preventing a sender from denying having sent a message. This is often achieved through cryptographic techniques, such as digital signatures, which bind the identity of the sender to the message content. Thus, if the sender later claims they did not send the message, the evidence provided by the digital signature can verify their involvement. While availability refers to ensuring that information and resources are accessible when needed, and integrity involves maintaining the accuracy and consistency of data, these concepts do not directly address the issue of sender accountability after a message has been sent. Authenticity is concerned with verifying the identity of users, systems, or messages but does not provide the same level of assurance regarding the sender's obligation to the message sent, which is the core focus of non-repudiation.