Accurate Local Timestamps

Legal time and traceability to official time sources is becoming increasingly important. Nowhere is this more apparent than in the financial sector where banking regulations are demanding legal accountability. New regulations demand that financial operations maintain timestamps traceable to national standard time sources. Adherence is typically demonstrated on an ad hoc basis by explaining how a system obtains its master clock source and providing logs of the system’s status. The procedures rely on various forms of machine-readable timestamps from time-link protocols and computer file systems. Without standardized timestamps even timekeeping experts may have difficulty verifying results. Further, these timestamps are not understandable to most people. This presents difficulty to lawyers, judges, and jurors who may be asked to evaluate timestamps in adversarial proceedings. People are most familiar with their own local time as represented in some Y-M-D h:m:s form, but there is no universally adopted format that is complete, technically accurate, and human readable. Many historical factors have thwarted standardization of a local timestamp format but this has recently become feasible. BCP 175 IANA Time Zone Database now provides credible local time information while RFC 7808 Time Zone Data Distribution Service specifies methods to automatically distribute time zone parameters and Leap Second metadata. Together they provide the underpinning for standardized local timestamps. We present a system called Common Calendar that produces binary and character timestamp formats providing technically accurate and human readable UTC based local time incorporating Leap Seconds and local time parameters. Systems and regulators could adopt its methods and formats to provide a robust timestamp system for general use and suitable for legal time.