EAC - Voluntary Voting System Guidelines

Name : | Hank Dietz
Organization : | University of Kentucky
Post Date : | 9/29/2005
Section Comments
Section : | 2.2.5.2.1
Page no. : | 2-6
Line no.: |
Comment : | The accuracy of time/date tracking and "time-and-date stamp" is never specified. Three such requirements seem appropriate: 1. Timekeeping mechanisms shall generate monotonically increasing time-and-date values. Discussion: some clock correction methods can cause time to be set back, potentially reordering the sequence of timestamped events; such methods are not acceptable during any period in which timestamps may be recorded. 2. The precision of the timekeeping mechanisms shall be sufficient to distinguish and properly order all audit records. For example, if the minimum possible time between events creating audit records is 1 second, then time must be recorded with a precision of no worse than 1/2 second (the Nyquist rate). 3. The accuracy of the timekeeping mechanisms relative to UTC (Coordinated Universal Time) may depend on application of a vendor-specified clock initialization procedure. After initialization, the timekeeping mechanisms must be accurate to within 1 minute at all times within a 15-hour polling period. Discussion: NIST and USNO time references (www.time.gov) are far more accurate, and higher accuracy is desirable, but many clock mechanisms exhibit significant drift due to temperature, etc., and simple correction methods for a fast local clock might violate the monotonic time requirement.