Recommendation ITU-T G.8273.2/Y.1368.2 specifies minimum requirements for time and phase for telecom boundary clocks and telecom time slave clocks used in synchronization network equipment that operates in the network architecture as defined in Recommendations ITU-T G.8271, ITU-T G.8271.1, ITU-T G.8275 and ITU-T G.8275.1. It supports time and/or phase synchronization distribution for packet-based networks. This version of the Recommendation only applies to full timing support from the network. These requirements apply under the normal environmental conditions specified for the equipment. Amendment 1 to Recommendation G.8273.2/Y.1368.2 provides the following updates: – Add a reference and one acronym – Changes in clauses 6.1 and 6.2 – Changes in clause 7.1 – Changes in Clause 7.5 – Adds Appendix IX