Post Syndicated from Bruce Schneier original https://www.schneier.com/blog/archives/2023/12/security-analysis-of-a-thirteenth-century-venetian-election-protocol.html

Interesting analysis:

This paper discusses the protocol used for electing the Doge of Venice between 1268 and the end of the Republic in 1797. We will show that it has some useful properties that in addition to being interesting in themselves, also suggest that its fundamental design principle is worth investigating for application to leader election protocols in computer science. For example, it gives some opportunities to minorities while ensuring that more popular candidates are more likely to win, and offers some resistance to corruption of voters.

The most obvious feature of this protocol is that it is complicated and would have taken a long time to carry out. We will also advance a hypothesis as to why it is so complicated, and describe a simplified protocol with very similar properties.

And the conclusion:

Schneier has used the phrase “security theatre” to describe public actions which do not increase security, but which are designed to make the public think that the organization carrying out the actions is taking security seriously. (He describes some examples of this in response to the 9/11 suicide attacks.) This phrase is usually used pejoratively. However, security theatre has positive aspects too, provided that it is not used as a substitute for actions that would actually improve security. In the context of the election of the Doge, the complexity of the protocol had the effect that all the oligarchs took part in a long, involved ritual in which they demonstrated individually and collectively to each other that they took seriously their responsibility to try to elect a Doge who would act for the good of Venice, and also that they would submit to the rule of the Doge after he was elected. This demonstration was particularly important given the disastrous consequences in other Mediaeval Italian city states of unsuitable rulers or civil strife between different aristocratic factions.

It would have served, too, as commercial brand-building for Venice, reassuring the oligarchs’ customers and trading partners that the city was likely to remain stable and business-friendly. After the election, the security theatre continued for several days of elaborate processions and parties. There is also some evidence of security theatre outside the election period. A 16th century engraving by Mateo Pagan depicting the lavish parade which took place in Venice each year on Palm Sunday shows the balotino in the parade, in a prominent position—next to the Grand Chancellor—and dressed in what appears to be a special costume.

I like that this paper has been accepted at a cybersecurity conference.

And, for the record, I have written about the positive aspects of security theater.