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- Welcome to the OCP Time Appliances Project wiki.
- This Project is open to the public and we welcome all those who would like to be involved.
- Time is one of the key elements to improve efficiency in a distributed system. Theoretically, the performance of a distributed system depends on the synchronization of its elements. Several industries such as telecom, mobile, power, industrial, professional audio and video and many more have embraced the need for highly accurate and more importantly reliable distribution and synchronization of time and frequency across packet networks. Although the use case scenario for each of the industries is different, they all share one common thing and that is, time synchronization. Since there is a diverse need for time synchronization across different industries, driven from different use cases and applications, managing the needs of this industry chain can become a challenge.
IEEE 1588 Precision Timing Protocol (PTP) and other synchronization methods have been adopted by various industries to maximize the efficiency of various distributed system use cases. Each use case scenario comes with a set of requirements and configurations. These configurations are collected as a ‘PTP profile’. Time appliances project aims to support the development of a PTP profile for datacenter applications and datacenter network infrastructure. The profile will cover time-sensitive applications over OCP-compliant and PTP-aware networking infrastructure such as network switches, network clocks, network interface cards, timing modules & connectors, etc. Additionally, the profile will address various requirements for high accuracy and reliable distribution and synchronization of time, such as expected performance, networking, software API, data models, deployment and telemetry. The project also aims at openness and interoperability through the use of open-source PTP software implementations for timing appliances.
IEEE P3335 Standard for Architecture and Interfaces for Time Card defines the generic architecture and interfaces of a time card system, which constitutes a traceable source of time-of-day to heterogeneous systems that distribute and/or use that time. Additionally, this standard defines figures of merit that univocally characterize the relevant performance of the Time Card. The Time Card provides a traceable time-of-day for systems directly attached to it, as well as networked distributed systems. Such systems include, but are not limited to, servers hosting the Time Card, and servers synchronized with the Time Card using such protocols as Precision Time Protocol (PTP) or Network Time Protocol (RFC Request for Comments) 5905). This standard also defines the basic building blocks of the Time Card and their interfaces in order to allow modularization. The main building blocks include time source, local oscillator, and time processor. Additionally, this standard defines interfaces between the Time Card and other systems. This includes physical interfaces that allow input and output of time-related signals. This also includes logical interfaces that are compatible with Portable Operating System Interface for UNIX (POSIX) and include for example an interface to share a Physical Hardware Clock (PHC). This allows sharing the time of day with other systems, as well as providing means for diagnostic and configuration. The definition of logical interfaces allows for a variety of Time Card's form factors (e.g. Peripheral Component Interconnect Express (PCIe)) while ensuring uniform support from the operating system. Any device that complies with this standard provides performance figures that are obtained following the specifications of this standard. As such, different implementations of the Time Card can be easily compared in terms of performance.
Datacenter applications are the primary target of time appliances project. In addition, the project extends to related topics on time synchronization in academia, research and other industries. The time appliances project brings together the community and will be highly collaborative through technical meetings and collaboration with other OCP Projects including the Networking, Storage, Server, and Telco Projects.
- Disclaimer: Please do not submit any confidential information to the Project Community. All presentation materials, proposals, meeting minutes and/or supporting documents are published by OCP and are open to the public in accordance to OCP's Bylaws and IP Policy. This can be found on the OCP OCP Policies page. If you have any questions please contact OCP.
- 1. Create specifications and references for Data Center Timing appliances, applications and networking infrastructure
- 2. Promote openness in Timing Appliances and interfaces through open-source implementations
- - Project Lead: [email protected] (OCP TAP | META)
- - Incubation Committee: [email protected] (OCP | NVIDIA)
| Project | Objective | Lead | Mailing List | Status | |
|---|---|---|---|---|---|
| #1 | Time Card | Development of the Time Card | [email protected] | Submitted | |
| #2 | Open Time Server | Development of an open time server for DC and Edge systems |
[email protected] [email protected] |
Submitted | |
| #3 | Data Center PTP Profile | Development of a PTP Profile tailored for data center applications | [email protected] | Submitted | |
| #4 | Precision Time APIs | Time APIs to disseminate the time error (error bound) and bring accurate time to the user space | [email protected] | OCP-TAP-APIs | Submitted |
| #5 | Oscillators | Classification and measuring of oscillators | [email protected] | Submitted | |
| #6 | PTP Servos | Design and Implement Advanced PTP Servos | [email protected] | Work in progress | |
| #7 | Instrumentation and Measurement | Open source instrumentation and measurement/testing tools for PTP |
[email protected] [email protected] |
Work in progress | |
| #8 | Precision Time Synchronization over Wireless | Open source Implementations of Precision Time Synchronization over Wireless |
[email protected] [email protected] |
Work in progress | |
| #9 | Precision Time Measurement Readiness Status | List of Hardware and Software with Precision Time Measurement Support |
[email protected] [email protected] |
Work in progress |
| Workstream | Name | Format | Version | Date |
|---|---|---|---|---|
| #1 | Open Time Server | Reference Architecture | v1 | July 28, 2021 |
| Time Card | Spec and design package | v1 | July 28, 2021 | |
| TAP Software | Software | v1 | July 28, 2021 | |
| #2 | Data Center PTP Profile | Spec | v2 | November 3, 2022 |
| v1 | August 31, 2021 | |||
| #4 | Classification and Measuring of Oscillators | Spec | v1 | January 8, 2022 |
- Wednesdays at 11am PST, starting on July 15th, 2020. Repeats every 2 weeks following that
- Zoom Room Link
- Meeting ID: 820 8566 5807
- +1 929 205 6099 US (New York)
- +1 301 715 8592 US (Washington DC)
- +1 312 626 6799 US (Chicago)
- +1 253 215 8782 US (Tacoma)
- +1 346 248 7799 US (Houston)
- +1 669 900 6833 US (San Jose)
| Date | Topics | Speakers | |
|---|---|---|---|
|
Apr-24, 2024 | T.B.D. | Marty Boyd, Ph.D. |
|
Apr-10, 2024 | Clock Coherence, from Terrestrial Microdatacenters to Alpha Centauri | Paul Borrill, Ph.D. |
|
Mar-27, 2024 | The future of UT1 vs UTC | Patrizia Tavella, Ph.D. |
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Mar-13, 2024 | What is Time? | Demetrios Matsakis, Ph.D. |
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Feb-28, 2024 | Reliable, Fast Failure Detection with Deterministic Interactions in Datacenters | Davide Rovelli |
|
Feb-14, 2024 | Precision Data Movement | Dan Biederman |
| Index | Date | Topics | Speakers | Slides |
|---|---|---|---|---|
|
Jan-31, 2024 | GNSS augmented sub-ns precision timing and 4 constellation NMA | Roel de Vries | Slides |
|
Jan-17, 2024 | Let's talk Servos - Key to Synchronization | Greg Armstrong | Slides |
|
Jan-03, 2024 | Precision Timekeeping Applications Discussion for Optical Atomic Clocks | Judith Olson, Ph.D. | Slides |
- - 2023 | OCP Global Summit | TAP Track
- - 2023 | OCP Regional Summit | TAP Track
- - 2022 | OCP Global Summit | TAP Track
- - 2022 | OCP Tech Talks | TAP Track
- - 2021 | OCP Global Summit | TAP Track
- - 2020 | OCP Tech Week | TAP Track
- - Impact of Oscillator Noise on PTP Time Error by SiTime | Slides Part 1 | Slides Part 2
- - International Timing and Sync Forum 2022 interviewing Ahmad Byagowi
- - "It's About Time (PTP on the Raspberry Pi)" video from Jeff Geerling Youtube Channel explains the effort on getting PTP on the Raspberry Pi
- - "Why is this PCIe Card RADIOACTIVE?" video from Linus Tech Tips Youtube Channel highlighting the TAP Time Card
- - "The most accurate Raspberry Pi clock IN THE WORLD! Can it do PTP?" video from Jeff Geerling Youtube Channel highlighting the TAP Time Card
- - "Put An Atomic Clock in Your PC - Open Source Time Card" video from Gary Explains Youtube Channel explains the TAP Time Card
- - "Facebook shares its Time Card atomic clock tech to speed internet services" article from C|Net
- - "Supercharges Precision Timing for Facebook’s Next-Generation Time Keeping" developer blog from NVIDIA
- - Spanner, TrueTime & The CAP Theorem by Eric Brewer, Google
- - Sundial: Fault-tolerant Clock Synchronization for Datacenters by Google Inc. and Harvard University
- - Practical Uses of Synchronized Clocks in Distributed Systems by Barbara Liskov
- - Stanford Paper
- - On Time Synchronization Issues in Time-Sensitive Networks with Regulators and Nonideal Clocks
- - Accurate Network Clock Synchronization at Scale
- - Exploiting a Natural Network Effect for Scalable, Fine-grained Clock Synchronization
- - SIMON: A Simple and Scalable Method for Sensing, Inference and Measurement in Data Center Networks
- - New Guidelines for Inclusiveness