It may seem counterintuitive that this is even possible, but this is exactly what a zero-knowledge protocol allows you to do.
So what is a Zero-knowledge Protocol?
A Zero Knowledge (ZK) protocol (often also referred to as a ZK proof) is a protocol that involves two parties:
1) a prover wanting to prove the correctness of a claim and
2) a verifier who needs to be convinced about the correctness of the claim.
For a protocol to be considered zero-knowledge, it must satisfy three properties:
Completeness: If the prover's claim is true, they should be able to complete the protocol successfully.
Soundness: The verifier should only be convinced if the prover’s claim is indeed true.
Zero Knowledge: The verifier learns nothing beyond the fact that the claim is true.
That is a nice definition but what can it be used for?
In today's world, verifying information about an individual usually involves sharing personal documents like a driver's license, identity card, or passport. Common to all these documents is that they usually contain more information than necessary. Consider if you are to prove that you are above 21.
You could do this by presenting your passport. However, this would most likely also reveal your full name, your precise date of birth, and a lot of other unnecessary information. ZK proofs offer a solution to this problem!
Proving your age with Zero-Knowledge proof
Imagine that you have a digital passport signed by relevant authorities. You could act as a prover in a ZK protocol to convince another party that you indeed are above 21 (if stated in your passport), proving the following statement in ZK:
“I possess a validly signed document stating a date of birth that shows that I am above 21”.
The completeness property of the ZK protocol would ensure that you could complete the protocol if your claim is true
and the soundness property would ensure that the verifier would indeed be convinced.
Furthermore, the zero-knowledge property would ensure that no information aside from what the statement says is revealed to the verifier.
Zero-knowledge protocols are a revolutionary tool in cryptography, allowing for secure and private verification of information. They enable you to prove the correctness of a claim without revealing any unnecessary details.
In a world where privacy and data security are increasingly important, ZK proofs offer a powerful solution for protecting personal information while still enabling verification. This transformative technology has the potential to change how we share and verify information, making interactions more secure and private.
The Partisia Platform: Beyond Zero Knowledge Proofs
At Partisia we employ advanced zero-knowledge protocols and even go one step beyond with Multi-Party-Computation (MPC). Whereas ZK protocols are limited to a prover convincing a verifier about a certain statement being correct, MPC protocols allow any number of parties to jointly compute their data without revealing anything but the result of the computation.
As we move towards 2026, these technologies will most likely play a crucial role in ensuring secure and privacy-preserving digital identities for EU citizens. Partisia is at the forefront of this transformation, providing innovative solutions that empower users with secure and controlled data activation.
Get to know more about our platform and how we will contribute to Next-gen Digital Identities.
