What is NTP and why is it important for security?
D4 · Operations · CompTIA Security+ SY0-701NTP (Network Time Protocol) synchronizes the clocks of computer systems over a network, ensuring all devices have consistent, accurate time. Security relevance of accurate time:
🕐 Log correlation — matching events across systems requires accurate timestamps
🎫 Kerberos — requires clocks within 5 minutes or authentication fails
📜 Digital certificates — validity periods depend on accurate time
🔄 Replay attack prevention — timestamps identify stale requests
NTP security risks: NTP amplification DDoS, NTP spoofing (falsifying time to disrupt Kerberos).
🕐 Log correlation — matching events across systems requires accurate timestamps
🎫 Kerberos — requires clocks within 5 minutes or authentication fails
📜 Digital certificates — validity periods depend on accurate time
🔄 Replay attack prevention — timestamps identify stale requests
NTP security risks: NTP amplification DDoS, NTP spoofing (falsifying time to disrupt Kerberos).
NTP runs on UDP port 123. If Kerberos authentication suddenly fails across an organization, suspect a time synchronization issue. NTPsec and authenticated NTP protect against NTP spoofing. Accurate time is foundational infrastructure — often overlooked but critical for security operations.