First White Rabbit Tutorial Workshop, Barcelona (Spain), 7 October 2017

With the occasion of the ICALEPCS 2017 conference, we are going to take the opportunity to organize a special type of workshop. Traditionally, WR workshops have been organized around contributions of WR users who come and show their latest developments. They are also a great time to discuss informally and catch up with the latest developments. This time we would like to cater also for potential WR users, people who have a problem to solve and would like to understand how WR can help them solve that problem. We therefore decided to organize the first WR tutorial workshop.

This format is adapted to typical attendees of the ICALEPCS conference. But we also would like to see the usual WR workshop crowd, because workshops also play this role of providing a place for people to meet and discuss, which is often perceived as even more useful than the actual technical presentations. We therefore decided to include some advanced topics in the program as well, so that everybody, including seasoned WR users and developers, can learn something new.

Preliminary agenda

Time Title Speaker(s)
09:30 - 10:00 Introduction to White Rabbit Javier Serrano
10:00 - 11:00 WR in action: distributed synchronization concepts and demo Dimitris Lampridis, Adam Wujek
11:00 - 11:30 Coffee break
11:30 - 12:30 Determinism in WR: priority handling and latency bounds with demo Maciej Lipiński
12:30 - 13:00 MIMO systems (with demo) and distributed oscilloscopes using WR Dimitris Lampridis, Tomasz Włostowski
13:00 - 14:00 Lunch break
14:00 - 14:30 Real-Time streaming of information using WR (with demo) Maciej Lipiński
14:30 - 15:30 Phase-compensated distribution of RF signals using WR (with demo) Tomasz Włostowski
15:30 - 16:00 Advanced diagnostics in a WR network Greg Daniluk, Adam Wujek
16:00 - 16:30 Coffee break
16:30 - 17:00 How to use the WR PTP Core to make your own WR nodes, advanced concepts Greg Daniluk
17:00 - 17:30 Calibration (with demo) and remote configuration of WR nodes Greg Daniluk
17:30 - 18:00 High-precision time and frequency distribution using WR Javier Serrano
18:00 - 18:30 Open floor for use cases, requests, ideas


Work in progress.

Introduction to White Rabbit

White Rabbit (WR) is an extension of Ethernet which provides determinism and a common notion of time to all nodes connected in the same network. By determinism we mean a guaranteed upper bound in message transport latency. The common notion of time is delivered using extensions to IEEE 1588 (PTP), currently undergoing a standardization effort. The accuracy of this common notion of time is better than 1 nanosecond. All the basic building blocks in WR are open source software, gateware and hardware. The talk explains the basic concepts behind WR and provides context for the more detailed talks which come later in the day.

Determinism in WR: priority handling and latency bounds with demo

This talk explains the mechanism to ensure determinism of message transport latency in White Rabbit, the possibilities enabled by this feature and its configuration. A professional IT tester will be used to demonstrate how the deterministic message transport latency works.

Real-Time streaming of information using WR (with demo)

White Rabbit cores provide a streaming facility/layer that can be used in WR Nodes - the WR Streamers VHDL module. The WR Streamers take advantage of WR's features (i.e. synchronization and determinism) to allow data streaming with low and fixed latency. This streaming facility is a building brick of a system that distributes the value of a magnetic field in CERN accelerators. This talk explains the WR Streamers, their integration into your design and their applications. The demonstration will illustrate how the WR Streamers are used at CERN.

Advanced diagnostics in a WR network

White Rabbit is an expansion of a regular Ethernet network. The same way you can diagnose off-the-shelf Ethernet switches and routers using a Simple Network Management Protocol (SNMP), you can also diagnose timing and data problems in your WR network. In this talk we will describe various SNMP objects that are exported by WR switches and WR nodes as well as how they can be analysed using Icinga (an open-source SNMP manager) to ensure correct operation of the network. Finally, we will emulate various failures that may occur in a typical WR installation, show how these can be detected and fixed.

How to use the WR PTP Core to make your own WR nodes, advanced concepts

White Rabbit PTP Core (WRPC) is the main element of every WR node. It is an HDL implementation of Gigabit Ethernet MAC including the full White Rabbit synchronization stack. This talk will provide a comprehensive description of the WRPC and its interfaces. We will present how user-defined HDL modules can benefit from the timing information provided by the core and how they can use the pipelined Wishbone interface for sending application-specific Ethernet frames. We will also see, how the WRPC instantiation in your own WR node can be simplified by using provided HDL wrappers for officially supported boards and FPGA platforms.

Calibration (with demo) and remote configuration of WR nodes

To ensure a sub-nanosecond synchronization, the White Rabbit software stack needs to estimate the communication link asymmetry. In this talk we will introduce the White Rabbit link delay model to characterize various factors that make the Master-to-Slave and Slave-to-Master link latencies not equal. To model these asymmetries we will demonstrate the calibration procedure that can be performed in the lab before the WR infrastructure is deployed. We will also show how to use a Simple Network Management Protocol (SNMP) to upload calibration parameters to the WR nodes.

High-precision time and frequency distribution using WR

The talk explains the phase noise formalism for studying and optimizing jitter through the use of Phase Locked Loops (PLL). We then move on to apply these concepts in the context of WR, identifying places in a WR link which impose constraints on any jitter optimization exercise, and discussing how to design a very precise time and frequency transfer system using WR.


Conference registration and workshop registration in ICALEPCS are independent, in the sense that you are free to register for the conference only, one or more workshops only, or both conference plus workshops. Details for workshop registration and venue are here, and the interface to register both for conference and workshops is available from here. ICALEPCS workshops traditionally involve a fee to help pay for the rent of the venue. The registration fee for this WR workshop is €90. It is also strongly recommended to reserve a lunch box during registration (€18.70) because the venue is far from restaurants and the lunch break is only 1 hour long.


If you would like to have more information about a specific subject or suggest changes to the program, feel free to contact Javier Serrano via email.