Quick scan multi-party-computation


We are performing a quick scan for a pilot with secure multi-party computation (MPC) in Amsterdam.
© www.comparitech.com

The Responsible Sensing Lab aims to make smart city systems more responsible on 4 levels: hardware, software, user-interface design and governance. On the software level, we are performing a quick scan to run a pilot with secure multi-party computation (MPC) in Amsterdam.

Multi-party-computation (MPC)

MPC is a cryptographic method that allows the analysis of different data sets without the need to share the data between parties. With this technique, repurposing data after an analysis with multiple parties is not possible. Also, MPC enables analyzing sensitive data without harming privacy or similar risks.

Zeki Erkin, associate professor at TU Delft and expert on MPC, is in the lead for the quick scan. Together with Zeki, we are looking for use cases that allow us to test MPC in Amsterdam. We see multiple opportunities in the mobility domain, in which many data are being produced and shared. The goal of a future pilot is to study how MPC could support the municipality in both data minimization and analyzing data without the risks that accompany data sharing. 

Data sharing for operational services and intelligence is crucial for a safe digital society. While doing so, it is also vital to protect our people against any privacy breaches. I believe MPC will play a key role in building safe and privacy-preserving solutions.”

— Dr. Zeki Erkin, Cybersecurity- en privacyconsultant en trainer bij ZEC Security en universitair hoofddocent bij TU Delft

A basic example of how MPC works

Main Image
Multiple parties collaborate to generate shared outcomes while the underlaying data remains hidden.

A basic example of how MPC works. Alice, Bob, Julia and Charles want to find out their group's average salary but don’t want to share how much they earn. The MPC protocol assigns each of them a secret, random value, the sum of which is equal to zero. The values are added to the salary figure which is shared with the MPC protocol. Now, the average salary can be calculated using the adjusted salary figures as the random values cancel out.

Comic 1 Drop Shadow
Comic 2 Drop Shadow
Comic 3 Drop Shadow
Comic 4 Drop Shadow
Calculating the average salary of a group using MPC

Zeki Erkin

Cyber security and privacy consultant and trainer at ZEC Security & Privacy and Associate Professor at TU Delft

TU Delft