Summary

Recommendation ITU-T G.8275.1/Y.1369.1 contains the ITU-T precision time protocol (PTP) profile for phase and time distribution with full timing support from the network. It provides the necessary details to utilize IEEE 1588 in a manner consistent with the architecture described in Recommendation ITU‑T G.8275/Y.1369.

Amendment 1 provides the following updates:

–           added ITU-T G.8271 to references;

–           addition of a new definition: special port (3.2);

–           clarification on the use of logMessageInterval in Delay_Resp messages (6.2.8);

–           clarification on the behaviour of the T-BC Announce message contents when the T-BC has a parent clock;

–           incremented the minor revision number of the profileVersion (Annex A);

–           correction to the handling of the alternateMasterFlag;

–           added informative text on the handling of the synchronizationUncertain flag (Annex E);

–           added monitoring of a PTP MASTER port by a PTP PASSIVE port (Annex G);

–           updates to Announce message fields of currentUtcOffset and synchronizationUncertain when using PTP clock states (Appendix V);

–           update of Appendix VII;

–           added informative use cases for the use of the priority2 attribute (Appendix X);

–           added considerations on native access equipment (Appendix XI);

–           added monitoring alternate master time information provided by a peer PTP port (Appendix XII).