The WBF’s dealing hands protocol

Following a proposal jointly put to the Management Committee by Maurizio Di Sacco and Hans van Staveren, in June 2018 the WBF decided to adopt a new protocol for producing computer dealt hands to be used at WBF events.

The original purpose is to avoid any possible suspicion about any kind of manipulation of the hands.

The ultimate goal is to set a standard for all organisers worldwide.

• At a defined moment ahead of a Championship the person responsible for generating and storing the hands – in WBF events Maurizio Di Sacco – randomly generates hexadecimal string of numbers which will be part of the one eventually used to produce the championship’s hands (for the World Series 2018 this was done on Monday September 10th).
• That number, called “the championship’s secret”, will be encrypted in such a way to be impossible to crack.
• The encrypted string will be officially published for everyone to know and store it.
• At the end of the championship the original string will be made public.
• At that point anybody can verify it is the original string: by applying the “ash” method to match the encrypted original code to the published one.
• However, somebody could still claim that the organisation tried a few strings and eventually selected the ones which better suited its purposes (eg using the one which produced wild sets of boards in the crucial rounds)
• To prevent that objection we must add to the string some part that is random, public, and that the organisation cannot control.
• At the moment the protocol claims for the Dow Jones index to be used: upon publishing the encrypted version of the championship’s secret we will also publish the date and the time of the day for the Dow Jones index to be used (for the 2018 World Series it was the DJI at the end of September 14th).
• After that date the whole string will be used to generate all the championship’s hands (for the 2018 World Series this was done any time from September 15th onward).
• In 2018, since the format of some events is not yet known (the number of entries is not final) the organisation produced the codes for the Rosenblum Cup, the Open Pairs, the Mixed Teams and the Mixed Pairs. The code for the other events will be generated once the format will be known.
• At the bottom of the page are the links to the original text documents generated by the program for various events. They include all the necessary information:

TN = Tournament Name
KH = Championship’s Secret Code
DI = Delayed Information (Dow Jones Index on September 14)
SN = Session: on the right there are the information about how many rounds, how many boards per session, how they are numbered in each of the phases and the hands’ file name.

e.g for the Rosenblum, the first SN line reads: 10 rounds; boards numbered cyclically 1-10, 11–20, 21-30; files named ROSQUAL (the ## means that the extension will have a two digit number, here from 01 to 10); event Rosenblum Qualification made out of 10 rounds.

Rosenblum Example:

TN Rosenblum 2018
KH 25e8f6fcb41f5b16a8fe8944f0d1f693345dac033d214abf0782daa5a87171b5
DI DJI 14/9/2018
SN 10:1-10,11-20,21-30:ROSQUAL##:Rosenblum Qualification #/10
SN 4:1-14,15-28:ROSR64#:Rosenblum Round of 64 #/4
SN 4:1-14,15-28:ROSR32#:Rosenblum Round of 32 #/4
SN 4:1-14,15-28:ROSR16#:Rosenblum Round of 16 #/4
SN 4:1-14,15-28:ROSQF#:Rosenblum Quarter Finals #/4
SN 4:1-14,15-28:ROSSF#:Rosenblum Semi Finals #/4
SN 6:1-16,17-32:ROSFIN#:Rosenblum Final #/6

Once the details are announced to be able to verify that the hands were not manipulated in any manner, you should now:

• Copy the Championship’s secret for the event you are interested in (linked below)
• Get a copy of squaredeal.exe at http://www.xs4all.nl/~sater/SquareDeal.zip (it includes documentation and instructions).
• Get familiar with the “ash” procedure
• At the end of the championship(s) look for the original hexadecimal string (to be published on the Championship’s Daily Bulletin and on the WBF website) and use it to generate the hands: they will correspond to the ones used in the event.

This is the code used for The 2019 World Bridge Teams