Summary

Recommendation ITU-T G.8275 specifies common aspects of phase and time profiles defined in [ITU-T G.8275.1] and [ITU-T G.8275.2]. This recommendation includes the precision time protocol (PTP) functions per [IEEE 1588] that are necessary to ensure interoperability for the delivery of accurate phase/time synchronization.

This new revision incorporates the following updates:

1) Split the contents of the previous revision of [ITU-T G.8275] into this new revision which addresses the common aspects of PTP profiles, and the recommendation [ITU-T G.8274] which addresses the PTP architecture aspects;

2) Revise the title of this recommendation as “Common aspects of PTP profiles for phase/time synchronization”, and rewrite the summary and scope;

3) Rewrite the summary, scope and clause 6;

4) Move the contents of clauses 7 and 9 of the previous revision of [ITU-T G.8275] into the recommendation [ITU-T G.8274];

5) Move the contents of Annex A, Appendix I, Appendix II, Appendix V, Appendix VII and Appendix X into the recommendation [ITU-T G.8274], and add a reference to the recommendation [ITU-T G.8274] for these annex and appendixes;

6) Improve some contents of Annex F;

7) Add a new Annex G “Synchronization service availability performance metrics (optional)”;

8) Add a new deployment case about IWF into Appendix III;

9) Add a new Appendix XIV “Calculation of offsetScaledLogVariance for T GM timed by PRTC or ePRTC”;

10) Add a new Appendix XV “Considerations of deploying ePRTC and PRTC in the network”;

11) Add a new Appendix XVI “Considerations on timer reconfiguration”.