Which time synchronization protocols are commonly used in OT networks to achieve accurate timestamps?

Which time synchronization protocols are commonly used in OT networks to achieve accurate timestamps?

• A. SSH and TLS
• B. NTP or PTP with a trusted time source
• C. DHCP and DNS
• D. SNMP and ICMP

Answer: (B)

Accurate timestamps in OT networks rely on dedicated time synchronization protocols that keep every device’s clock aligned. The best fit here are NTP and PTP. NTP is widely used to synchronize clocks across devices, providing reliable timing for many applications. PTP, on the other hand, is designed for high-precision, deterministic synchronization and often uses hardware timestamping to achieve sub-microsecond accuracy. In OT settings, this level of precision is crucial for correlating events, sequencing control actions, and producing coherent logs across distributed equipment. That precision is achieved when the clocks are disciplined to a trusted time source, such as a GPS-based grandmaster or another secure reference, ensuring the entire network shares the same, tamper-resistant time base. The other options don’t fit because they serve different roles: SSH and TLS are for securing communications, not keeping time; DHCP and DNS provide IP addressing and name resolution; SNMP and ICMP are for network management and diagnostics, not time synchronization.

Accurate timestamps in OT networks rely on dedicated time synchronization protocols that keep every device’s clock aligned. The best fit here are NTP and PTP. NTP is widely used to synchronize clocks across devices, providing reliable timing for many applications. PTP, on the other hand, is designed for high-precision, deterministic synchronization and often uses hardware timestamping to achieve sub-microsecond accuracy. In OT settings, this level of precision is crucial for correlating events, sequencing control actions, and producing coherent logs across distributed equipment. That precision is achieved when the clocks are disciplined to a trusted time source, such as a GPS-based grandmaster or another secure reference, ensuring the entire network shares the same, tamper-resistant time base.

The other options don’t fit because they serve different roles: SSH and TLS are for securing communications, not keeping time; DHCP and DNS provide IP addressing and name resolution; SNMP and ICMP are for network management and diagnostics, not time synchronization.