Zero Knowledge Proof in Blockchains
There are two significant challenges concerning the use of personal data in or with blockchains, which Sedicii’s ZKP (Zero Knowledge Proof) technology can address.
A key feature of a blockchain is decentralisation. This means that no central administrator or application logic is required in order to run it. Instead, the whole blockchain acts as a consensus mechanism to ensure all nodes stay in sync, enabling each one of them, independently, to verify every single transaction.
Decentralisation is important since it guarantees there is no single point of failure. That is, the blockchain is not affected in the event that an attacker corrupts the data in a few chain nodes. Moreover, in order for an attacker to control the blockchain, he would need to hack more than half of its nodes, which in most blockchains requires computational resources beyond the reach of any person or organization on the planet.
However, decentralisation comes at the cost of privacy. Every node on the chain must verify every transaction independently, and this in turn means that it sees what everyone else is doing.
Secondly, privacy legislation, particularly the EU General Data Protection Regulation (GDPR), requires the “right to be forgotten”, whereby personal data has to be deleted and purged in a system. If this right were applied to a blockchain containing personal data, the deletion of any data in the blockchain would break the chain, causing a ‘hard fork ’ or worse, to destroy the chain altogether.
Hence, there is a need to have the means to use blockchains to manage personal data, without having personal data on the blockchain itself. ZKP is one of the most important breakthroughs in cryptography in the last few decades, with extensive applications in the domain of digital identity protection. Most notably, ZKP solves these two privacy problems in blockchains.