priority2: 255 for slave-only transparent clock primary syntonization domain: 0 (default) Additions to IEEE Std 1588 IEC 62439-3 Annex C specifies requirements in addition to IEEE 1588: A clock shall accept both 1-step and 2-step corrections (improves plug-and-play) All clocks can be doubly attached using the IEC 62439-3 protocol (PRP "Parallel Redundancy Protocol" or HSR "High-availability Seamless Redundancy") Several master clocks can be active at the same time; the slave selects the best master. Time-outs ensure that the clocks can detect the loss of PTP messages also on the unused path. Identification of the peer node to check the topology of the network and ensure that all elements support the protocol. In network using store-and-forward media converters and for L2P2P only, the master appends a padding to Sync messages to ensure that Sync and Pdelay_Req/Pdelay_Resp messages have the same size (this will specified in IEEE 1588:2017) Network management by SNMP according to IEC 62439-3 Annex E Standard owners This protocol has been developed by the IEC SC65C WG15 in the framework of IEC 62439, which applies to all IEC industrial networks. To avoid parallel standards in IEC and IEEE in the field of grid automation, the L2PTP profile specific to grid automation previous IEC 62439-3 Annex B has been placed under the umbrella of the IEC&IEEE Joint Development 61850-9-3. Technical responsibility rests with IEC SC65C WG15, which is committed to keep the IEC 62439-3 profile L2P2P and IEC/IEEE 61850-9-3 aligned. References External links IEC 61588:2009 Precision clock synchronization protocol for networked measurement and control systems IEC/IEEE 61850-9-3, Communication networks and systems for power utility automation – Part 9-3: Precision time protocol profile for power utility automation IEC TR 61850-90-4:2013 Communication networks and systems for power utility automation - Part 90-4: Network engineering guidelines Tutorial on HSR Tutorial on Parallel Redundancy Protocol (PRP) Tutorial on the precision time protocol industrial profiles in IEC 62439-3 IEC 62439-3 Tissues (Technical issues) database for IEC 62439-3 / IEC/IEEE 61850-9-3 Networking standards Network protocols