How zero-knowledge technology can enhance digital public infrastructure

Nations have long invested in physical infrastructure: the walls, bridges, highways and other structures that support everything we do. In today’s technological age, there is an equal need to enhance the digital architecture necessary to carry the online load.

The September 2023 G20 meeting under India’s presidency emphasized the role of “safe, secure, trusted, accountable and inclusive digital public infrastructure respectful of human rights, personal data, privacy and intellectual property” in fostering resilience while enabling service delivery and innovation. The New Delhi Declaration adopted at the G20 meeting also recognizes the importance of cross-border data flows and data free flow, with trust to ensure that different digital systems work together seamlessly.

As countries increasingly invest in digital public infrastructure, technologies that make such infrastructure safe, secure and trustworthy are needed.

To understand the need for securing digital public infrastructure, it’s helpful to first understand what it means. The term can be tough to define at times – so much so that the United Nations Development Programme calls it “an evolving concept”.

The growing consensus is that it is a shared set of digital systems, based on open source technology standards that enable governance and innovative players across both the public and private spheres. Importantly, it helps deliver innovations at scale. Thao Hong, a programme officer for the Bill & Melinda Gates Foundation, adds that “strong digital public infrastructure” typically includes digital infrastructure in three crucial areas: identity, payments and data exchange.

All these factors are critical aspects of digital public infrastructure. However, just as bridges or pipes would be useless if they were built on unstable foundations, digital public infrastructure must also be built to last – with security and privacy at its core.

While digital public infrastructure initiatives can be a major force for reducing inequality, improving global health, and promoting more sustainable economic growth, it also puts massive amounts of potentially sensitive data in the hands of the public and private institutions managing it. As the use of digital public infrastructure evolves from identity and payments to diverse sectors (such as health, education and agriculture), there is an increasing need to ensure that data sharing happens in a privacy-preserving secure manner.

Limiting data transfers to avoid security risks comes at a cost: even a 1-point increase in data restrictiveness cuts a nation’s productivity by nearly 3% and its gross trade output by 7%. As such, finding a way to share enough data to keep commerce flowing without compromising privacy and security is critical.

Zero-knowledge technology is an innovative cryptographic (coded) framework that makes it possible for one party to verify the claims of another without actually revealing any of the underlying data behind their claim. Using this technology, governments and other entities could confirm certain facts about their users while minimizing the amount of data exchange in cross-sectoral and cross-border transactions.

As such, digital public infrastructure supported with zero-knowledge technology can potentially create a trustworthy and secure environment for high-value and high-impact transactions, at scale. As an illustration:

Using zero-knowledge technology benefits governments and private entities alike, because neither have to store any more information than is necessary, reducing their risk of being the targets of damaging cyberattacks. That’s not a small benefit: data breaches are expected to cost the world $10.5 trillion annually by 2025.

Zero-knowledge technology could function at various levels. It could be incorporated at the infrastructure level or at the application level, depending upon the context and use case. While zero-knowledge technology can function outside of blockchain, its integration with blockchain infrastructure can help solve additional challenges posed by cross-border data transfers (specifically by ensuring resiliency and secure data storage, eliminating the need for complex international data sharing standards).

Digital public infrastructure is an enabler and requires diverse stakeholders to use the infrastructure to create value for society and the economy. “Investors, tech companies, international organizations, civil society groups, entrepreneurs and independent programmers all have roles to play,” writes economist Bhaskar Chakravorti.

As G20 members agree on the need for a voluntary framework for the development, deployment and governance of digital public infrastructure, zero-knowledge technology can be an important module in the digital public infrastructure toolkit to ensure that the infrastructure and its applications remain privacy-preserving and secure by design.

A relatively new technology, it needs to be tested and optimized for various use cases, as well as intuitive front-end systems, to ensure adoption. Public-private partnerships will be crucial to ensure we are taking advantage of the right technology, working with a wide range of software developers and being mindful of consumer behaviour.