Page 47 - U4SSC Blockchain for smart sustainable cities

The outcomes of the intervention, once fully It is also not determined if it is critical to remove
developed, will be an application that provides the intermediaries or whether a permanent
a simple, reliable way to verify claims while record of the data is required along with writing
ensuring greater privacy, as individuals do access. While centralized control of the system
not need to reveal personal data. There is is required, it is not necessary to implement a
the potential for providing new services and contractual relationship and it is essential to
improving the processes surrounding existing store sensitive data. With these specificities,
services, which include claim verification. All blockchain might be a relevant, but unsuitable
this takes place in the context of a large, funded, technology.
collaborative consortium, which has been set However, further exploring blockchain
up in the face of concerns about increasing technologies remains a good opportunity
privacy risks and the need for compliance with a because the DECODE tools being developed
range of regulations. It is expected to contribute provide a basis for developing a range of solutions,
positively to social sustainability. linked to principles of individual ownership of
Even though the users of the system are not personal data, decentralization and flexibility in
known, and it is essential to work with digital terms of the underlying technologies.
assets, it is not clear whether the relationships
between the entities and the users are based on
trust or not.

Lessons learned and conclusions

• It is possible to use blockchain with zero-knowledge proof and attributes-based credentials to prove
claims with limited exposure of personal data.
• Prototypes can be used to illustrate the technology’s capabilities and are useful for understanding
the potential applications in cities.
• Instead of approaching technology in terms of “I want it to work” or “it has to be easy”, there has
been a perspective shift on technology, architecture, and how that relates to power, ownership,
agency and privacy. Concepts including zero-knowledge proof, and encryption (and their impor-
tance) all need to be better understood.
• A policy document has been developed to inform policymakers and provide them with recommen-
dations in the fields of privacy and digital identity.

U4SSC: Blockchain for smart sustainable cities 37