Mina strives to be the smallest blockchain in the world and claims that its protocol maintains a constant size of around 22 kilobytes. This is supposedly achieved through the use of recursive zk-SNARKs – the same technology used by the privacy-focused cryptocurrency Zcash (ZEC). While the latter uses this technology to offer its users more data protection, the latter uses it for the sake of scalability.
A zk-SNARK, which stands for a succinct, non-interactive argument of knowing without knowledge, enables a party to prove that they have certain information without revealing what that information is. It is similar to how a smartphone can recognize its owner without storing the person’s actual identity data.
There has been a lot of discussion about using zk-SNARKs to scale various protocols including Bitcoin, although there are few practical uses of the technology at the moment. Evan Shapiro, CEO of O (1) Labs, the company behind the Mina blockchain, said that while it’s a nice idea, his team had to solve many technological challenges to bring this concept to life:
“It’s a very neat and beautiful idea on a high level. But once you start to actually implement it you have to be aware of a lot of complexities and actually manage to get it done. “
When it comes to the nodes of the project, their size depends on the needs of the network. A “normal” node only needs a few kilobytes, while a node that participates in the consensus needs about one gigabyte:
“If you’re a normal node that just needs trusted, permissionless access to a few accounts, it’s in the kilobyte range because you only need the proof and actual accounts. If you want to reach consensus, you need all accounts. Let’s say a million accounts. Each is a hundred bytes, probably a little more, like kilobytes. So you need a gigabyte to store that. “
Originally the project was planned with a consensus on proof of work, but the team decided earlier this year to adopt the Ouroboros consensus from Cardano. Even so, significant efforts have been made to adapt this system to the knowledge-free cryptography used by Mina. Unlike Zcash, which is just a cryptocurrency, Mina has an intelligent contract layer and its own version of decentralized applications or DApps called Snapps.
Shapiro said Mina’s other distinction is that it will be able to safely consume external data without the need for oracles. This combination of external data and knowledge-free cryptography could open up a number of use cases. With Mina, for example, users could provide decentralized finance apps with the parameters of their credit history without having to disclose what information is actually involved. This, in turn, could lead to lower inherent risks and lower interest rates for borrowers. Users may be able to use the information about Know Your Customer verified by an intermediary to bypass the verification requirements of another crypto service provider.
Mina recently changed its name from “Coda” due to a lawsuit by the R3 Consortium that believed the name was too close to its own “Corda”. Mina mainnet is expected to launch in the next few months.