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Into the Future with Metrology - The Challenges of Digitalization

Transparent and anonymous elections

Blockchain technology for electronic voting

PTBnews 3.2022
Especially interesting for

manufacturers and testers of voting machines

carInternational e-voting network

Digital voting systems allow citizens to make democratic decisions even when sociopolitical challenges (e.g., the COVID-19 pandemic, war, or natural disasters) prevent voters from getting to the ballot box. PTB has conducted type approvals of voting machines since 1999 in accordance with the Bundeswahlgeräteverordnung (German Federal Voting Machine Ordinance). Building on this work, PTB launched an international e-voting research network that today consists of six servers, two in Brazil at INMETRO, one in Japan at NMIJ, one in Malaysia at NMIM, one in the Czech Republic at CMI, and one at PTB in Berlin.

In collaboration with these international metrology institutes, an approach for e-voting systems based on blockchain technology was developed. Each voter receives a token that is randomly and uniquely generated. Using these tokens, voters can change their votes as often as they like until the end of the election without sacrificing anonymity. The token itself is saved in a blockchain. Since the blockchain prevents any removal or manipulation of tokens, each voter is able to identify his or her ballot when the votes are tallied. The voters themselves also make an active contribution to the anonymization of the election. Each voter is provided with a number of electronic ballots, which they then shuffle by means of so-called mix networks. This ensures that the ballots cannot be traced to the original voter. At the end of the election, the ballots can be viewed by anyone and they are unalterable. This means that each voter has the opportunity to transparently verify that his or her vote has been counted and that the election result has not been manipulated.

A patent application for this procedure was filed early on by PTB.


Daniel Peters
Department 8.5
Metrological Information Technology
Phone: +49 30 3481-7916
Opens local program for sending emaildaniel.peters(at)ptb.de

Scientific publication

D. Peters, F. Thiel: E-Voting: I changed my mind, now what? Future Technologies Conference 2022. 20–21 October 2022. Vancouver, Canada, to be published