ITU-T G.8272.1 (ePRTC) One-Page Summary

Title: Timing characteristics of enhanced primary reference time clocks

Summary

• Enhanced Primary Reference Time Clock equipment specification

• Provides an accurate time reference into the network, using a 1pps output port

• Typical implementation based on GNSS

• Jitter/wander based on Enhanced PRC specification (G.811.1)

Status

• Current version: 1st. Edition, November 2016, plus Amendment 1, August 2017
• Download from: http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=13162
• Enhancements in progress: addition of a PTP time output port

Key Contents

Time Accuracy

• While locked to GNSS, with clear sky view: within 30ns of UTC (or applicable primary time standard)
• In holdover: within 100ns of UTC (or applicable primary time standard) for up to 14 days

Functional Model

Wander

Holdover