PCI Data Security Standard Practice Test

Time stamps in security event logs must line up across all systems so you can accurately trace what happened and when. The reliable way to achieve that is to obtain time settings from industry-accepted time sources—typically through network time protocol (NTP) servers that are synchronized to UTC from trusted reference clocks (like GPS or radio time). This provides a single, authoritative time reference that all devices can use, so every log entry shares a common baseline. Relying on a local server clock invites drift, and clocks on different devices drift at different rates, causing mismatched timestamps that break event correlation. Manually inputting time is slow, error-prone, and not scalable—any lapse in updating times across devices can create gaps or misalignment in logs. Satellite time signals can feed a time service, but the robust approach is to rely on centralized, industry-accepted time sources that your network devices consistently query, ensuring accuracy and redundancy across the logging infrastructure.