Title: Timing characteristics of telecom grandmaster clocks for frequency synchronization

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Summary

• Packet-Based Equipment Master Clock for Frequency (PEC-M-F)

• Takes PRC-quality input and generated PTP output

• Based on the G.812 Types I, II or III clocks (SSU clocks)

• Specifies frequency accuracy, noise generation, noise tolerance, holdover, testing methods

Status

• Current version: 1st. Edition, November 2016, plus Amendment 1, March 2018

• Download from: http://www.itu.int/ITU-T/recommendations/rec.aspx?rec=13106

Key Contents

• Three types of clocks: Type I (Europe), Types II and III (N. America)

• Performance characteristics based on the equivalent G.812 Types I, II or III:

  • Frequency accuracy (free-run)

  • Wander generation (but measured through a low-pass filter of 0.1Hz)

  • Wander tolerance

  • Wander transfer

  • Transient response and holdover

• Functional model:

Open