New White Rabbit Switch 4.0 - request for comments and Workshop

Dear White Rabbits,

The two documents that propose hardware architecture and features of the New White Rabbit 4.0 switch are now available on the WRS-4 project website (

Your feedback is very much appreciated. Please provide it by writing to the forum or sending me an email (, ideally before the dedicated workshop takes place (see below), at latest by the end of June. You can also provide the feedback during the workshop.

We would like to organize a half-day online workshop dedicated to the proposed New White Rabbit Switch architecture/features in the second half of June. Preliminary agenda:

  • Introduction to the New WR Switch project, roadmap, work packages.
  • Presentation of the proposed architecture and features.
  • Digest of received feedback, time for more feedback and discussion.

We propose the following days/times (Geneva time):

June 19: 8h30 - 12h30 (Friday)
June 19: 13h30 - 17h30 (Friday)
June 22: 13h30 - 17h30 (Monday)
June 24: 13h00 - 17h00 (Wednesday)
June 25: 13h00 - 17h00 (Thursday)
June 26: 8h30 - 12h30 (Friday)
June 26: 13h30 - 17h30 (Friday)

Please, fill in the doodle with your availability by 15 June June 2020, Monday (end of day):

Apologies for a relatively short notice. Still, I do hope that we will find a date/time convenient to most of the interested participants.


1 Like

Dear White Rabbits

The workshop will take place on Friday, June 26, 13h30-17h30 using zoom.
The call-in details are posted below. I’ll provide more detailed agenda closer to the workshop.

Your feedback to the documents prior to the meeting is appreciated.
Looking forward to e-meeting you all at the workshop.


Topic: New WRS-4 Workshop
Time: Jun 26, 2020 01:30 PM Zurich

Join Zoom Meeting

Meeting ID: 993 1556 7248
Password: 511430
One tap mobile
+41432107042,99315567248# Switzerland
+41432107108,99315567248# Switzerland

Dial by your location
+41 43 210 70 42 Switzerland
+41 43 210 71 08 Switzerland
+41 31 528 09 88 Switzerland
+33 1 7037 9729 France
+33 7 5678 4048 France
+33 1 7037 2246 France
Meeting ID: 993 1556 7248
Find your local number:

Join by SIP

Join by H.323
Meeting ID: 993 1556 7248
Password: 511430

About the 10 MHz output, I would go for an AC coupled output instead of LVCMOS 3.3.
With the proposed clock scheme it’s also easy (just convert differential LVPECL to single-ended with a balun) and already robust against user mistakes (shorts, DC power supply,…) without additional components.

Dear All,

Many thanks for so numerous participation in the New WRS-4 workshop and all your feedback.

The feedback has been organized into isses in the wr-switch-hw-v4 project:✓&state=all

You can see that many input was already marked “To be included” while we are working on others (“To be investigated further” and “To be discussed”). We will likely contact some of you directly regarding the inputs to be discussed.

Out of all issues, we would need more information on some. I could not remember their author, it would be great if you could have a look and provide input if relevant to you.