Richard Cochran, release engineer for the LinuxPTP Project, announced the release of version 4.0 of linuxptp:

It has been almost three years since the previous linuxptp release. The number of individual contributors has nearly doubled since the last release. Thank you to our developers.

This release includes both new and improved features and many minor bug fixes. Users are encouraged to upgrade. The most notable changes are as follows.

• Officially supports the 2019 version of IEEE 1588

  In a sense, linuxptp has always supported IEEE 1588 v2.1, simply because that standard is backwards compatible with the v2.0 version from 2008. This release makes it official by advertising 1588 version 2.1 in generated messages.

• Improved unicast messaging

  This release features numerous improvements to unicast transport, making the behavior both more rational and more correct.

• Enhanced G.8275.2 profile

  The G.8275.2 now supports the NO_MECHANISM mode, preventing delay request generation, and interface rate reporting for calculating delay asymmetry.

• More flexible Pulse Per Second (PPS) handling

  The PPS program, ts2phc, may now synchronize in either direction from PPS source to sink or the reverse. In addition it can use the improved periodic waveform generation API when supported by the kernel.

• Virtual clock support

  Recent Linux kernels feature so called “virtual clocks” running on top of a free-running physical clock. This release adds support for such clocks.

• Power profile support

  IEEE C37.238 is now supported in both the 2011 and 2017 editions.

• Other various improvements

  • VLAN over bond support.

  • Parallel Redundancy Protocol (PRP) trailer handling.

  • Non-privileged read-only monitoring port.

  • New statistics reporting.

Refer to Richard’s announcement for the list of contributors and the full changelog for this release.