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# White Rabbit Standardization in IEEE1588 Precision Time Protocol
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# White Rabbit Standardization in IEEE1588 Precision Time Protocol
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The White Rabbit (WR) extension of the IEEE1588-2008 standard has being
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The White Rabbit (WR) extension of the IEEE1588-2008 standard has been
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generalized into a text of the 2019 edition of the standard (IEEE1588-2019).
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generalized into a text of the 2019 edition of the IEEE1588 standard (IEEE1588-2019).
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The standardization process of WR has finished with the publication of IEEE1588-2019
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The standardization process of WR finished with the publication of IEEE1588-2019
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on 15 June 2020. The generalized White Rabbit (under the name High Accuracy) is
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on 15 June 2020. The generalized White Rabbit (under the name High Accuracy) is
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the third default PTP Profile included in Annex I of the IEEE1588-2019.
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the third default PTP Profile included in Annex I of the IEEE1588-2019, along with a number of optional features; see details of [White Rabbit integration into IEEE1588-2019 as High Accuracy](https://www.ohwr.org/projects/wr-std/wiki/wrin1588).
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This wiki page provides details regarding the White Rabbit extension and
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its standardization in IEEE1588.
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This wiki page documents the project of WR standardization that started in 2012 and finished in 2020.
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The goal of the project was to transform the White Rabbit extension of IEEE1588 into a recognized standard. The feasibility of the project goal, the target standard, the means and process of standardizing were all within the scope of this project.
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# White Rabbit Standardization Project
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## Introduction
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## Introduction
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*White Rabbit** (WR) is an extension of the IEEE1588-2008 (*Precision
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*White Rabbit* (WR) is an extension of the IEEE1588-2008 (*Precision
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Time Protocol*, PTP) standard. The WR extension has been developed to
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Time Protocol*, PTP) standard. The WR extension has been developed to
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synchronize nodes in a packet-based network with sub-ns accuracy.
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synchronize nodes in a packet-based network with sub-ns accuracy.
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Achieving such high accuracy results from the combination of
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Achieving such high accuracy results from the combination of
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IEEE1588-2008 (*Precision Time Protocol*, PTP) with the following
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IEEE1588-2008 with the following
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further extensions:
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further extensions:
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1. clock syntonization over the physical layer (similar to SyncE),
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1. Clock syntonization over the physical layer (similar to SyncE),
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2. enhancement of timestamps precision through phase detection,
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2. Enhancement of timestamps precision through phase detection,
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3. automatic precise evaluation of link asymmetry.
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3. Automatic precise evaluation of link asymmetry.
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White Rabbit evolved into an extension of the Precision Time Protocol
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White Rabbit evolved into an extension of the Precision Time Protocol
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(PTP) and is therefore referred to as WRPTP.
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(PTP) and is therefore referred to as WRPTP.
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*WRPTP is fully compatible with PTP and is currently being defined as a
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**WRPTP is fully compatible with PTP and is defined as a PTP Profile.**
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PTP Profile.**
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The solutions in WRPTP are have been included by the [P1588 Working
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Group](https://sagroups.ieee.org/1588/) in the new
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revision of the PTP standard, i.e. IEEE1588-2019. This is
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described in [White Rabbit integration into IEEE1588-2019 as High Accuracy](https://www.ohwr.org/projects/wr-std/wiki/wrin1588).
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-----
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-----
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... | @@ -38,8 +36,8 @@ described in [White Rabbit integration into IEEE1588-2019 as High Accuracy](http |
... | @@ -38,8 +36,8 @@ described in [White Rabbit integration into IEEE1588-2019 as High Accuracy](http |
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The White Rabbit Protocol is defined in the White Rabbit Specification
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The White Rabbit Protocol is defined in the White Rabbit Specification
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(WR Spec) that describes:
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(WR Spec) that describes:
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- hardware requirements for implementing WRPTP
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- Hardware requirements for implementing WRPTP,
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- protocol requirements for WRPTP-compatibility
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- Protocol requirements for WRPTP-compatibility.
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### White Rabbit Specification material
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### White Rabbit Specification material
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... | @@ -49,9 +47,9 @@ The White Rabbit Protocol is defined in the White Rabbit Specification |
... | @@ -49,9 +47,9 @@ The White Rabbit Protocol is defined in the White Rabbit Specification |
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- [older versions of the WR
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- [older versions of the WR
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Specification](https://www.ohwr.org/project/wr-std/wikis/Documents/White-Rabbit-Specification-(Revision-History)) (to show how
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Specification](https://www.ohwr.org/project/wr-std/wikis/Documents/White-Rabbit-Specification-(Revision-History)) (to show how
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the WR Spec evolved)
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the WR Spec evolved)
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- [short information regarding different versions](Revisions) (i.e.
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- [Short information regarding different versions](Revisions) (i.e.
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feedback, comments, diffs)
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feedback, comments, diffs)
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- [issues and possible improvements to the current
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- [Issues and possible improvements to the current
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version](WrSpecV2issues)
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version](WrSpecV2issues)
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-----
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-----
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... | @@ -59,16 +57,16 @@ The White Rabbit Protocol is defined in the White Rabbit Specification |
... | @@ -59,16 +57,16 @@ The White Rabbit Protocol is defined in the White Rabbit Specification |
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## Standardization benefits and paths
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## Standardization benefits and paths
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Standardizing White Rabbit is unquestionably beneficial to the project
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Standardizing White Rabbit is unquestionably beneficial to the project
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and its users and is expected to bring a substantial boost to the number
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and its users and brings a substantial boost to the number
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of WR applications.
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of WR applications.
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Advantages of standardization:
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Advantages of standardization:
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- easier co-operation with companies
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- Easier co-operation with companies,
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- increase of stability, viability, and credibility of the White
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- Increase of stability, viability and credibility of the White
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Rabbit solution
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Rabbit solution,
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- feedback of experts that enables to polish the solution and make it
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- Feedback of experts that enables to polish the solution and make it
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more mature
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more mature and robust.
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Standardization is a considerably long process that can be approached in
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Standardization is a considerably long process that can be approached in
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various ways and from various directions. Potential paths (see
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various ways and from various directions. Potential paths (see
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... | @@ -78,12 +76,12 @@ for WR's standardization had been identified as follows: |
... | @@ -78,12 +76,12 @@ for WR's standardization had been identified as follows: |
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- [Standardization at the International Telecommunication Union-
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- [Standardization at the International Telecommunication Union-
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Telecommunication Standardization Sector
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Telecommunication Standardization Sector
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(ITU-T)](ITU-Tstandardization)
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(ITU-T)](ITU-Tstandardization)
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- within Telecom Profile (G.827x) - currently being developed
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- within Telecom Profile (G.827x)
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- as a separate Profile (similar to Telecom)
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- as a separate Profile (similar to Telecom)
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- [Standardization at the Institute of Electrical and Electronics
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- [Standardization at the Institute of Electrical and Electronics
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Engineers (IEEE)](IEEEstandardization)
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Engineers (IEEE)](IEEEstandardization)
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- as an IEEE1588 PTP Profile
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- as an IEEE1588 PTP Profile
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- included into version 3 of PTP (PTPv3) (**this is the chosen way
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- included into next revision of IEEE1588 (PTP) (**this is the chosen way
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of WR standardization**)
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of WR standardization**)
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- as a part of
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- as a part of
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[AVB](http://www.ieee802.org/1/pages/avbridges.html) Gen2,
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[AVB](http://www.ieee802.org/1/pages/avbridges.html) Gen2,
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... | @@ -96,19 +94,20 @@ for WR's standardization had been identified as follows: |
... | @@ -96,19 +94,20 @@ for WR's standardization had been identified as follows: |
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## White Rabbit standardization within the IEEE1588 revision process
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## White Rabbit standardization within the IEEE1588 revision process
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Including White Rabbit into the IEEE1588 (PTP) standard has been
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Including White Rabbit into the IEEE1588 (PTP) standard has been
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identified as the best and feasible WR standardization path.
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identified as the best and feasible WR standardization path.
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White Rabbit was proposed to be included into PTP as a *High Accuracy
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White Rabbit was proposed to be included into PTP as a *High Accuracy
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Option/Profile*
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Option/Profile*
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([presentation](https://www.ohwr.org/project/white-rabbit/uploads/442e2b2eca547f69b85c28ff465ce240/WRspecialSession_Maciej_ISPCS2012.pdf),
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([presentation](https://www.ohwr.org/project/white-rabbit/uploads/442e2b2eca547f69b85c28ff465ce240/WRspecialSession_Maciej_ISPCS2012.pdf),
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[document](https://www.ohwr.org/project/white-rabbit/uploads/b0c0f513bf8734bc856f6860fa693201/ISPCS2012-specialSession-final.pdf))
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[document](https://www.ohwr.org/project/white-rabbit/uploads/b0c0f513bf8734bc856f6860fa693201/ISPCS2012-specialSession-final.pdf))
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at the Special Session of
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at the Special Session of
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[ISPCS2012](http://www.ispcs.org/2012/index.html). This Special Session
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[ISPCS2012](http://www.ispcs.org). This Special Session
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showed an interest and need for reasonably broad IEEE1588 revision. The
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showed an interest and need for reasonably broad IEEE1588 revision. The
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first step in revising PTP was the preparation of Project Authorization
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first step in revising PTP was the preparation of Project Authorization
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Request (PAR) by a Study Group at the beginning of 2013. The PAR states
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Request (PAR) by a Study Group at the beginning of 2013. The PAR states
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that the revised protocol "enhances support for synchronization to
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that the revised protocol "enhances support for synchronization to
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better than 1 nanosecond" which reflects the enthusiasm of the group to
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better than 1 nanosecond" which reflects the enthusiasm of the group to
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evaluate White Rabbit extensions.
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evaluate incorporation of the White Rabbit extensions into the standard.
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The revision process of the IEEE1588 Precision Time Protocol (PTP)
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The revision process of the IEEE1588 Precision Time Protocol (PTP)
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standard started in mid-2013. The revision work was performed by the [P1588
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standard started in mid-2013. The revision work was performed by the [P1588
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... | @@ -123,9 +122,9 @@ to a broader range of applications and include these generalized |
... | @@ -123,9 +122,9 @@ to a broader range of applications and include these generalized |
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solutions in the IEEE1588 standard.
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solutions in the IEEE1588 standard.
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- [P1588 Working Group](https://sagroups.ieee.org/1588/)
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- [P1588 Working Group](https://sagroups.ieee.org/1588/)
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- P1588 Subcommittee *High Accuracy*: Co-chairs: John MacKay
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- **High Accuracy** P1588 Subcommittee: Co-chairs: John MacKay
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([Progeny Systems Corporation](http://www.progeny.net/)) and
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(Progeny Systems Corporation) and
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Maciej Lipinski ([CERN](http://home.cern)). Sec/Editor: Geoff
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Maciej Lipinski (CERN). Sec/Editor: Geoff
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Garner (Consultant for Huawei Technologies Co., Ltd.)
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Garner (Consultant for Huawei Technologies Co., Ltd.)
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- [IEEE1588-2008 standard](http://ieeexplore.ieee.org/document/4579760/), available
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- [IEEE1588-2008 standard](http://ieeexplore.ieee.org/document/4579760/), available
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through IEEE Explore Digital Library (payable)
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through IEEE Explore Digital Library (payable)
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... | @@ -137,7 +136,7 @@ solutions in the IEEE1588 standard. |
... | @@ -137,7 +136,7 @@ solutions in the IEEE1588 standard. |
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## Goal of this project
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## Goal of this project
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The goal of this project is to standardize the White Rabbit Protocol.
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The goal of this project is to standardize the White Rabbit extension of the IEEE1588-2008 standard.
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## Project plan
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## Project plan
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... | @@ -153,12 +152,15 @@ The goal of this project is to standardize the White Rabbit Protocol. |
... | @@ -153,12 +152,15 @@ The goal of this project is to standardize the White Rabbit Protocol. |
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identified, studied and evaluated
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identified, studied and evaluated
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3. The most suitable path (in terms of costs, efforts, time)
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3. The most suitable path (in terms of costs, efforts, time)
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decided (the end of 2012)
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decided (the end of 2012)
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2. Standardization of White Rabbit within
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2. Standardization of White Rabbit
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[P1588](https://ieee-sa.centraldesktop.com/1588public/)
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1. The standardization effort (started in February 2013)
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1. The standardization effort started (February 2013)
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2. Publication of a standard that includes White Rabbit marks the end of
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2. An official standardization of White Rabbit marks the end of
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the project
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the project
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## Selected documents/presentations
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-
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## Project's timeline
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## Project's timeline
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||**Task**|**End date**|
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||**Task**|**End date**|
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