Accurate timekeeping in data centers: a resiliency review

Precision time systems to synchronize IT system clocks over the network have proliferated and evolved to meet the needs of reliable, secure applications. Performance, cost and potential vulnerabilities drive the choice of technology and implementation.

KEY POINTS

• Organizations should evaluate their data center infrastructure timekeeping systems regularly to ensure they meet changing application and business requirements for accuracy and resiliency.
• Almost all IT workloads require accurate timekeeping — that is, synchronization to a reference clock within a defined tolerance. Some applications require accuracy within microseconds, orders of magnitude more accurate than other applications. Less time-sensitive workloads may still demand greater accuracy for security, data backups and incident forensics.
• Organizations have a choice of time synchronization systems. These differ in their typical accuracy, hardware specifications, resiliency and vulnerabilities. Time as a service vendors offer accurate synchronization via service level agreements (SLAs) in place of hardware maintenance obligations.
• Many implementations depend on satellite systems, such as the Global Positioning System (GPS), for low-cost accurate time reference. Sole dependence on GPS creates a single point of failure; a resilient data center time infrastructure needs to include redundant equipment or backup sources of reference time. Without safeguarding measures, GPS dependence also creates additional security risks.