ITU-T Y.1369.1 PDF

This Recommendation specifies a profile for telecommunication applications based on IEEE 1588 precision time protocol (PTP). The profile specifies the IEEE 1588 functions that are necessary to ensure network element interoperability for the delivery of accurate phase/time synchronization. The profile is based on the full timing support from the network architecture as described in [ITU-T G.8275] and definitions described in [ITU-T G.8260].

This version of the profile specifies the high-level design requirements, modes of operation for the exchange of PTP messages, the PTP protocol mapping, the best master clock algorithm (BMCA) options, as well as the PTP protocol configuration parameters.

NOTE 1 − The parameters defined in this version of the profile are chosen based on the case where physical layer frequency support is provided, and the case without physical layer frequency support (i.e., PTP only) is for further study.

This Recommendation also specifies some aspects necessary for use in a telecom environment that are outside the scope of and complement the PTP profile.

NOTE 2 – [b-IEEE 1588-2019] specifies a new PTP version 2.1. Based on clause 19 of [b-IEEE 1588-2019], PTP version 2.1 is inter-operable with PTP version 2.0, which is specified in IEEE Std 1588-2008 [IEEE 1588]. Therefore, it is expected that PTP version 2.1 can be used in this profile. Further details about the use of PTP version 2.1 in this Recommendation are for further study. The intention is that an ITU-T G.8275.1 implementation based on PTP version 2.1 will be compatible/inter-operable with existing deployments using PTP version 2.0, as long as no new PTP functionality that is not present in PTP version 2.0 is used.