What is Network Time Security (NTS)?

• A. A security layer that verifies the trustworthiness of NTP responses
• B. A protocol for time zone updates
• C. A method to speed up time synchronization
• D. A DNS-based authentication mechanism

Answer: (A)

Network Time Security adds cryptographic protection to the time distribution process, providing a security layer that lets clients verify that NTP responses are authentic and have not been tampered with. It achieves this by performing a separate key-establishment step to establish shared keys, then using those keys to authenticate NTP messages, which prevents spoofed or replayed time data from being trusted. This directly addresses the risk of attackers delivering false time information. It isn’t about updating time zones, speeding up synchronization, or DNS-based authentication, which is why the security-focused option that emphasizes trustworthiness of NTP responses is the correct choice.