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White Rabbit
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cf8e2b87
Commit
cf8e2b87
authored
Mar 19, 2024
by
Javier Serrano
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Intro to WRWS13
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Title Page Info %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\title
[Introduction to the event\hspace{18em}\insertframenumber/\inserttotalframenumber]
{
Introduction
}
% \subtitle{And some notes on GMT and BST}
% \author[CERN\hspace{17em} Maciej Lipi\'{n}ski]{Maciej Lipi\'{n}ski}
% \author[European Organization for Nuclear Research $\mid$ Maciej Lipi\'{n}ski]{Maciej Lipi\'{n}ski}
% \author[Maciej Lipi\'{n}ski $\mid$ European Organization for Nuclear Research]{Maciej Lipi\'{n}ski}
\author
[Javier Serrano on behalf of the CERN WR Team]
{
Javier Serrano on behalf of the CERN WR Team
}
\institute
{
European Organisation for Nuclear Research
\\
(CERN)
}
\date
[21 March 2024]
{
WR workshop and WR Collaboration Launch
Event
\vspace
{
0.5cm
}
\\
21 March 2024
}
\AtBeginSection
[]
{
\begin{frame}
<beamer>
{
Outline
}
\tableofcontents
[currentsection]
\end{frame}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Begin Your Document %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
%\setbeamertemplate{caption}{\raggedright\insertcaption\par}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\frame
{
\titlepage
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
<beamer>
{
Outline
}
\tableofcontents
\end{frame}
\section
{
Introduction
}
\subsection
{}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
{
What is White Rabbit?
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{columns}
[c]
\column
{
0.65
\textwidth
}
\footnotesize
% \textcolor{white}{dddd dsaf asd fasd fdsa fads f dsa fdsa f dsaf dsa fdsa f dsaf dsaf fds}
\begin{itemize}
\item
Initially meant for Big Physics facilities/projects: CERN,
GSI, Nikhef
\ldots
\item
\textbf
{
Based on well-established standards
}
\begin{itemize}
\scriptsize
\item
Ethernet
\textcolor
{
gray
}{
(IEEE 802.3)
}
\item
Bridged Local Area Network
\textcolor
{
gray
}{
(IEEE 802.1Q)
}
\item
Precision Time Protocol
\textcolor
{
gray
}{
(IEEE 1588)
}
\end{itemize}
\item
\textbf
{
Extends standards
}
to meet new requirements and provides
\begin{itemize}
\scriptsize
\item
\color
{
blue
}{
Sub-ns synchronisation
}
\item
\color
{
blue
}{
Deterministic data transfer
}
\end{itemize}
\item
Initial specs: links
$
\leq
$
10~km
\&
$
\leq
$
2000 nodes
% \item<7-> Initial network specification:
% \begin{itemize}\scriptsize
% \item Fiber links length: $\leq$10~km
% \item Number of nodes: $\leq$2000
% \end{itemize}
\item
\textbf
{
Open Source and commercially available
}
% \item<9-> Many users worldwide, inc. metrology labs...
\end{itemize}
% \textcolor{white}{dddd dsaf asd fasd fdsa fads f dsa fdsa f dsaf dsa fdsa f dsaf dsaf fds}
% \textcolor{white}{dddd dsaf asd fasd fdsa fads f dsa fdsa f dsaf dsa fdsa f dsaf dsaf fds}
\textcolor
{
white
}{
dddd dsaf asd fasd fdsa fads f dsa fdsa f dsaf dsa fdsa f dsaf dsaf fds
}
\column
{
0.55
\textwidth
}
\begin{center}
\includegraphics
[height=0.7\textheight]
{
network/wr
_
network-enhanced
_
pro
_
without
_
10km.pdf
}
% \includegraphics<3>[width=0.85\textwidth]{misc/LAN.jpg}
% \includegraphics<4>[width=0.8\textwidth]{misc/ieee-1588-ptp-example.jpg}
% \includegraphics<5>[width=1.0\textwidth]{network/WR_network-ethernet.pdf}
% \includegraphics<6->[width=1.0\textwidth]{network/wr_network-enhanced_pro-v2.pdf}
\end{center}
\end{columns}
%\small\pause\pause\pause\pause\pause\pause\pause\pause
% \url{https://www.ohwr.org/projects/white-rabbit/}
\end{frame}
%% \Section{Technology}
%% \subsection{}
\begin{frame}
{
White Rabbit technology - sub-ns synchronisation
}
\begin{block}
{
Based on
}
\begin{itemize}
\item
IEEE 1588 Precision Time Protocol on Gigabit Ethernet over fibre
\end{itemize}
\end{block}
\pause
\begin{block}
{
Enhanced with
}
\begin{itemize}
\item
Layer 1 syntonisation
\item
Digital Dual Mixer Time Difference (DDMTD)
\item
Link delay model
\end{itemize}
\end{block}
\end{frame}
\section
{
Community
}
\subsection
{}
\begin{frame}
{
Short history of WR
}
\begin{itemize}
\item
2008: first meeting at CERN
\item
2009: first switch prototype
\item
2012: first COTS switch available (open-source hardware, gateware,
firmware, software)
\item
2012: first operational deployment of WR (Gran Sasso National Lab)
\item
2013-2018: WR concepts standardised within IEEE 1588
\item
2024: creation of the WR Collaboration
\end{itemize}
\end{frame}
\begin{frame}
{
WR post-standardisation
}
\begin{center}
\includegraphics
[width=1.0\textwidth]
{
misc/WR
_
Workshop
_
2022
_
scaled.jpg
}
\\
A technology supported by a friendly community working on a fully open-source
implementation of IEEE 1588-2019 High-Accuracy (HA) profile, with a guaranteed
sub-nanosecond accuracy.
\end{center}
\end{frame}
\section
[WR Collaboration]
{
The White Rabbit Collaboration
}
\subsection
{}
\begin{frame}
{
Entering a new phase
}
\begin{block}
{
Post-standardisation issues
}
\begin{itemize}
\item
How to maintain good support after the increase in uptake of the
technology, both in industry and academia?
\item
How to ensure a high level of quality in the foundations of WR
(switch and WR PTP core)?
\end{itemize}
\end{block}
\end{frame}
\begin{frame}
{
White Rabbit Collaboration
}
\begin{center}
\includegraphics
[height=0.5\textheight]
{
logo/WRC
_
logo
_
all
_
blue
_
on
_
white.jpg
}
\\
See next presentation and visit
\\\href
{
https://www.white-rabbit.tech/
}{
https://www.white-rabbit.tech/
}
\end{center}
\end{frame}
\section
[Logistics]
{
Logistics for this event
}
\subsection
{}
\begin{frame}
{
Logistics
}
\begin{itemize}
\item
The Globe
\item
Lunch
\item
CERN visits this evening
\item
Dinner tonight
\item
Presentations:
\begin{itemize}
\item
See guidelines at
\href
{
https://ohwr.org/project/white-rabbit/wikis/Workshop-Presentation-Guidelines
}{
https://ohwr.org/project/white-rabbit/wikis/Workshop-Presentation-Guidelines
}
\item
Bear in mind times in schedule include Q
\&
A and transition between speakers
\end{itemize}
\item
Let's start!
\end{itemize}
\end{frame}
%% \section{Summary}
%% \subsection{}
%% \begin{frame}{Summary}
%% \begin{itemize}
%% \item A versatile, standards-based solution for sub-nanosecond
%% synchronisation.
%% \item Used in Physics and beyond, standardised under IEEE Std 1588-2019.
%% \item Fully open source (hardware, gateware, firmware, software): solid basis
%% for evolution and customisation.
%% \item Now entering a new phase through the creation of the WR Collaboration.
%% \end{itemize}
%% \end{frame}
\appendix
\backupbegin
\begin{frame}
{
Backup slides
}
\begin{center}
Backup slides
\end{center}
\end{frame}
\begin{frame}
{
Precision Time Protocol (IEEE 1588)
}
\begin{columns}
[c]
\column
{
.4
\textwidth
}
\begin{center}
\includegraphics
<1>[height=5cm]
{
protocol/ptp
_
exchange-enhanced.jpg
}
\includegraphics
<2->[height=4cm]
{
protocol/ptpNetwork.jpg
}
\end{center}
\column
{
.75
\textwidth
}
\begin{itemize}
\item
Frame-based synchronisation protocol
\item
Simple calculations:
\begin{itemize}
\item
link delay:
$
\delta
_{
ms
}
=
\frac
{
(
t
_{
4
}
-
t
_{
1
}
)
-
(
t
_{
3
}
-
t
_{
2
}
)
}{
2
}$
\item
offset from master:
$
OFM
=
t
_{
2
}
-
(
t
_{
1
}
+
\delta
_{
ms
}
)
$
\end{itemize}
\item
<2-> Hierarchical network
\item
<3-> Shortcomings of traditional PTP:
\begin{itemize}
\item
devices have free-running oscillators
\item
frequency drift compensation traffic can compromise determinism of
other messages
\item
assumes symmetry of medium
\item
resolution of timestamps
\end{itemize}
\end{itemize}
\end{columns}
\end{frame}
\begin{frame}
{
Layer 1 Syntonisation
}
%\begin{block}{Common clock for the entire network}
\begin{itemize}
\small
\item
Clock is encoded in the Ethernet carrier and recovered by the receiver chip
\item
All network devices use the same physical layer clock
\item
Clock loopback allows phase detection to enhance precision of timestamps
% \item Phase detection allows sub-ns delay measurement
\end{itemize}
%\end{block}
\vspace
{
-0.2cm
}
\begin{center}
\includegraphics
<1>[height=5cm]
{
misc/synce
_
v3.pdf
}
% \includegraphics[height=4.5cm]<2>{p1588/1588-ha-L1vsPTP-simplified.jpg}
\end{center}
\end{frame}
\begin{frame}
{
Digital Dual Mixer Time Difference (DDMTD)
}
\begin{itemize}
\item
Precise phase measurements in FPGA
\item
WR parameters:
\begin{itemize}
\scriptsize
\item
$
clk
_{
in
}
~~~~~~~~
=
62
.
5
$
~MHz
\item
$
clk
_{
DDMTD
}
=
62
.
496185
$
~MHz (N=14)
\item
$
clk
_{
out
}
~~~~~~
=
~~
3
.
814
$
~kHz
\end{itemize}
\item
Theoretical resolution of 0.977~ps
\end{itemize}
\vspace
{
-0.2cm
}
\begin{center}
\includegraphics
[width=\textwidth]
{
misc/ddmtd
_
3.jpg
}
\end{center}
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% \begin{frame}{SoftPLL}
% \begin{center}
% \includegraphics[width=.9\textwidth]{protocol/dmpll_diagram-slides.pdf}
% \end{center}
% \end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
{
Link delay model
}
\begin{columns}
\column
{
.65
\textwidth
}
\footnotesize
\begin{itemize}
\item
<1->Correction of Round Trip Time (RTT) for asymmetries
\item
<2->Asymmetry sources: FPGA, PCB, electrical/optical conversion,
chromatic dispersion
\item
<3->Link delay model:
\begin{itemize}
\scriptsize
\item
\textbf
{
Fixed delays
}
-- calibrated/measured
\item
\textbf
{
Variable delays
}
-- evaluated online with:
\vspace
{
0.1cm
}
$
\alpha
=
\frac
{
\nu
_
g
(
\lambda
_
s
)
}{
\nu
_
g
(
\lambda
_
m
)
}
-
1
=
\frac
{
\delta
_{
ms
}
-
\delta
_{
sm
}}{
\delta
_{
sm
}}$
\end{itemize}
\item
<4-> Accurate offset from master (OFM):
\scriptsize
\\\vspace
{
0.2cm
}
% $RTT=(t_{4}-t_{1}) - (t_{3}-t_{2})$\\
$
\delta
_{
ms
}
~
=
\frac
{
1
+
\alpha
}{
2
+
\alpha
}
\,
(
RTT
-
\sum
\Delta
-
\sum
\epsilon
)
$
\vspace
{
0.2cm
}
$
OFM
=
t
_{
2
}
-
(
t
_{
1
}
+
\delta
_{
ms
}
+
\Delta
_{
txm
}
+
\Delta
_{
rxs
}
+
\epsilon
_
S
)
$
\end{itemize}
\column
{
.5
\textwidth
}
\begin{center}
\includegraphics
<1>[width=0.8
\textwidth
]
{
protocol/link-delay-model-detailed-1.jpg
}
\includegraphics
<2>[width=0.8
\textwidth
]
{
protocol/link-delay-model-detailed-2.jpg
}
\includegraphics
<3->[width=0.8
\textwidth
]
{
protocol/link-delay-model-detailed-3.jpg
}
\\\pause\pause\pause
%\tiny See: \textit{WR Calibration} [9]
\end{center}
\end{columns}
% \pause\pause\pause\pause
% \scriptsize See: \textit{WR Calibration}, version 1.1, G.Daniluk
\end{frame}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
{
High Accuracy in IEEE 1588
}
\begin{center}
\includegraphics
[width=0.8\textwidth]
{
p1588/HAin1588-5.jpg
}
\end{center}
\end{frame}
\section
{
Status and Plans
}
\subsection
{}
\begin{frame}
{
Status
}
\begin{block}
{
Fundamental building blocks
}
\begin{itemize}
\item
Recent release of WR PTP Core v5.
\item
Upcoming software/gateware release (v7) for WR switch v3 hardware.
\end{itemize}
\end{block}
\end{frame}
\begin{frame}
{
Plans
}
\begin{block}
{
WR Switch v4
}
\begin{itemize}
\item
GbE and 10GbE support
\item
Redundant and serviceable fans and power supplies
\item
Based on Xilinx/AMD Zynq UltraScale+ System-on-Chip (SoC)
\item
Expansion board slot for enhancements (low phase noise, hold-over
\ldots
)
\end{itemize}
\end{block}
See
\href
{
https://ohwr.org/project/wr-switch-hw-v4/wikis
}{
https://ohwr.org/project/wr-switch-hw-v4/wikis
}
for more details.
\end{frame}
\begin{frame}
{
WR Switch v4
}
\begin{center}
\includegraphics
[height=0.7\textheight]
{
switch/wrs
_
v4
_
design-1.jpg
}
\\
Prototypes next month, v3 functionality before the end of the year.
\end{center}
\end{frame}
\begin{frame}
{
Standardisation++
}
\begin{center}
\includegraphics
[width=\textwidth]
{
calibration/absolute
_
calibration
_
detail.png
}
\end{center}
\begin{flushright}
Courtesy Henk Peek and Peter Jansweijer
\end{flushright}
\end{frame}
\begin{frame}
{
Standardisation++ (P. Jansweijer, M. Lipi
\'
{
n
}
ski)
}
\begin{block}
{
Amendments to IEEE 1588-2019
}
\begin{itemize}
\item
Absolute calibration
\item
In-situ calibration of asymmetry
\end{itemize}
\end{block}
\begin{block}
{
Within the SNIA SFF working group
}
Storage of calibration parameters in SFP EEPROM
\end{block}
\end{frame}
\begin{frame}
{
Future developments
}
\begin{block}
{
My guess at a WR user wishlist
}
\begin{itemize}
\item
Monitoring: switch front panel and programming interface
\item
Robustness of hardware
\item
Seamless system redundancy (clock ensemble)
\item
More automation in calibration
\item
Evolution of link delay model
\item
Standardisation/profiles
\item
Set of best practices for long-distance WR
\item
Lower barrier to entry: training, starting kit, documentation
\ldots
\end{itemize}
\end{block}
Join the newly-created White Rabbit Collaboration to help us shape the future
of WR!
\end{frame}
\begin{frame}
{
The White Rabbit Collaboration in a nutshell
}
\begin{block}
{
Ensuring sustainability
}
\begin{itemize}
\item
Members pay a yearly fee and shape the future of the technology.
\item
Fees are used to pay the WR Collaboration Bureau, which offers
support (including training) and ensures WRS and WRPC are always in good health.
\end{itemize}
\end{block}
\end{frame}
\begin{frame}
{
The White Rabbit Collaboration in a nutshell
}
\begin{block}
{
Letting information flow
}
\begin{itemize}
\item
Collaboration with vendors ensures coherent growth of the WR
ecosystem
\item
Keeping members well informed: online presentations, forum, regular
meetings
\ldots
\item
Connecting people, institutes, companies (e.g. connecting NRENs with
industry)
\end{itemize}
\end{block}
\end{frame}
\begin{frame}
{
The White Rabbit Collaboration in a nutshell
}
\begin{block}
{
Ensuring high-quality
}
\begin{itemize}
\item
Making the evolution of WRS and WRPC the main task of the Bureau
\item
Teaming up with laboratories to establish a set of tests and
qualification criteria
\item
Connecting the use of the WRC logo to the successful passing of those
tests
\end{itemize}
\end{block}
\end{frame}
\begin{frame}
{
The White Rabbit Collaboration in a nutshell
}
\begin{block}
{
Projects!
}
\begin{itemize}
\item
Mobile (e.g. TDD on 5G)
\item
Quantum: see e.g. CERN's Quantum Tech Initiative at
\href
{
https://quantum.cern/
}{
https://quantum.cern/
}
\item
Smart grids
\item
$
<
$
your project here
$
>
$
\end{itemize}
\end{block}
\end{frame}
%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{frame}
{
Open
\textbf
{
and
}
commercially available off-the-shelf
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\includegraphics
[width=0.8\textwidth]
{
misc/WR-zoo.jpg
}
\vspace
{
-1cm
}
\begin{center}
\small
\textbf
{
Companies selling White Rabbit:
}
\url
{
www.ohwr.org/projects/white-rabbit/wiki/wrcompanies
}
\end{center}
\end{frame}
\backupend
\end{document}
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