Table of Contents - G.8272.1 (2024) Amd. 1 (07/2025) -

1	Scope
2	References
3	Definitions
4	Abbreviations and acronyms
5	Conventions
6	Time error, wander and jitter in locked mode
	6.1	Time error in locked mode
	6.2	Wander in locked mode
	6.3	Jitter
7	Phase discontinuity
8	Transient response and holdover performance
	8.1	Transient between time locked and frequency reference locked
	8.2	Phase/time holdover based on frequency reference during loss of phase/time input
	8.3	Recovery from holdover
9	Interfaces
	9.1	Phase and time interfaces
	9.2	Frequency interfaces
Annex A – ePRTC autonomous primary reference clock requirements
Appendix I – ePRTC functional model
Appendix II – ePRTC holdover model
	II.1	General clock model
	II.2	Ideal holdover model
	II.3	ePRTC holdover performance characterization
Appendix III – Testing ePRTC holdover
Appendix IV – ePRTC locked mode duration and holdover period
Appendix V – ePRTC parametric holdover
Appendix VI – ePRTC used as a travelling clock
Bibliography