IEEE 1588 Working Group

What is the current version of PTP?

The IEEE1588-2019 standard specifies the Precision Time Protocol v2.1 (PTP v2.1).

  • v2.1 identifies the Precision Time Protocol version – the numbering here is intended to signify the v2.1 protocol is backward compatible with protocol v2.0. The PTP message header actually includes the v2.1  (See section 7.5.4 of 1588-2019.)
  • 1588-2019 identifies the standard – the descriptive text that spells out what the protocol should be. Here the numbering is intended to signify the relative positioning of when the standard was released.

The various IEEE1588 documents standard versions (1588-2002, 1588-2008 and 1588-2019) are independent of the protocol version – there could be a 1588-2023 that also targets v2.1 of the protocol. So far:

  • IEEE1588-2002 specifies PTP v1
  • IEEE1588-2008 specifies PTP v2
  • IEEE1588-2019 specifies PTP v2.1 (the minor number was added in this edition of the standard)