DECODE (DEcentralised Citizen-owned Data Ecosystems) was an experimental project to enable practical alternatives to how we manage our personal data and interact on the internet. DECODE developed technology that puts people in control of their personal data, giving them the ability to decide how it is shared. The technology will include an architecture for controlled and, if desired, anonymised data sharing, paving the way for the creation of a ‘data commons’.

DECODE tested this technology in four pilots, in Amsterdam and Barcelona, between 2017 and 2019. The pilots trialled the technology and demonstrate the wider social value that comes with individuals being given control of their personal data the means to share it differently.

Through these pilots DECODE explored how to build a data-centric digital economy where data that is generated and gathered by citizens, the Internet of Things (IoT), and sensor networks is available for broader communal use, with appropriate privacy protections. Our aim was to enable the foundations of a new approach to data, whereby innovators, startups, NGOs, SMEs, co-operatives, and local communities to take advantage of that data to build apps and services that respond to their needs and those of the wider community. In this vision, cities can have a strong role, as custodians of these new digital rights of citizens.

The four DECODE pilots were:


Barcelona Pilots

Digital Democracy and Data Commons. This pilot involved the Barcelona City Council and the city’s digital democracy software Decidim.org, which has more than 60K users. The platform integrated a DECODE module which allows petitions to be signed anonymously but still in line with authentication requirements, such as place of residence. This new system for citizen petitions gives people more granular control over their data. It enhances privacy (via the DECODE app), allows data sharing and visualization (via the BCNOW dashboard) and transparency (via the DECODE distributed ledger).    

The pilot also opened a deliberative, participatory process on the politics and economics of data, and how Barcelona could constitute a democratic city data commons. More info on the pilot here

Citizen Science Data Governance.  In this pilot residents used environmental sensors which recorded factors such as noise levels and pollution. The sensors were located inside their homes and in their neighbourhood. DECODE technology enabled them to share this encrypted data anonymously with their communities, on their own terms. The pilot ran sessions to train and support participants to help them setup and use the  sensors to gather and analyse data to influence city-level decisions. The pilot tackled the technical challenges of collating and storing a stream of citizen-sensed data, while also enabling those citizens to control what information is shared with whom, and under which conditions. This was run in collaboration with Barcelona community organisations Ideas for Change and FabLab Barcelona.

To read the full report of the Barcelona pilots, please see our publication here

Amsterdam Pilots 

Amsterdam Digital Register - age check with municipal census data. This pilot gave citizens access to personal data that is stored in the municipal database, and allowed them to share these data in a different context, on- or offline. In the pilot, participants used DECODE technology to prove their age, as it certifies that they are over 16 or 18 years of age, without having to share their full identity or social security number. This pilot used Attribute Based Credentials, a data minimising authentication mechanism.

Gebiedonline (Neighbourhood Online). GebiedOnline is a local neighbourhood social network in Amsterdam. Access to  GebiedOnline is currently managed by email/password or Facebook login. This creates unwanted dependencies and security issues. This pilot tested a more privacy-preserving local social network. The Gebiedonline board and community want their platform to be open source, inclusive and to enable their users to have granular control over the data they share with the platform and with other users in the community. To achieve this the pilot built and tested a feature to allow access to the platform using Attribute Based Credentials. Since several communities are active on the platform, each community can decide on which credentials it can accept. To read the full report of the Amsterdam pilots, please see our publication here