Nash has upgraded our client protocols to generate signatures with secure multi-party computation (MPC), the technology behind our decentralized API keys. Our non-custodial blockchain wallets can now offer hardware-level security at no cost!
This upgrade means that users’ full private keys no longer play a role in signing transactions on Nash. Instead, transactions are co-signed with Nash via MPC, enabling us to enforce security policies like address whitelisting and withdrawal limits.
Users can still store their seed phrase and private keys offline for use with third-party wallets, giving them full access to their funds if Nash is offline – just like the paper backup of a hardware wallet seed phrase.
Unlike hardware wallets, however, Nash accounts are completely free and have the look and feel of familiar online platforms. What’s more, with configurable security policies, they are arguably safer than hardware. If your Nash login is hacked, the damage an attacker can do is limited.
Thanks to MPC, holding the keys to your crypto became safer and easier!
A blockchain approves or refuses a transaction by verifying its signature. A private key is one way of generating a valid signature. If you have the private key for an address, you can always sign transactions going out of that address.
However, there are other ways of generating signatures that do not give one party all the power. By splitting the generation of signatures between two parties, it becomes impossible for one party to approve transactions unilaterally.
This can be achieved using secure multi-party computation (MPC), where two parties must collaborate to generate a valid blockchain signature. Using our new protocol, both Nash and a user have their own key. These keys each generate what is known as a “pre-signature”. The two pre-signatures are then combined into a single valid signature.
MPC makes it possible for users to set up specific permissions associated with their account – for instance, a withdrawal address whitelist or withdrawal limits. If a user attempts to withdraw too much, or to the wrong address, Nash will withhold its pre-signature and nothing will happen.
Of course, Nash alone is also unable to issue or authorize any transaction. The system is designed such that the user is the only one capable of initiating transactions. It remains non-custodial.
You can hear our Applied Research team – Nash co-founder Ethan Fast and applied cryptographer Robert Annessi – discuss MPC on Episode 1 of our podcast Beyond the Chain.
Here’s a more technical overview of how Nash’s MPC protocol is implemented. First, we describe how keys are set up when the user creates an account, then how they are used on subsequent logins.
So, Nash has access to one sub-key but not the other. The user retrieves their sub-key by logging in, getting an encrypted data package from Nash and decrypting it. This all happens automatically with keys derived from user login information.
In the event that their sub-key is compromised, a user can log in and revoke it, and an attacker does not have the power to do anything with the blockchain funds in their account. Users can also retrieve their encrypted master secret from Nash to recover their full private key information by passing additional 2FA and email verification rounds.
The Nash wallet system represents a significant advance over current popular solutions for storing cryptocurrency.
Nash’s MPC-based system overcomes all these issues. Nash wallets are fully non-custodial, but at the same time offer advanced security unlike other software wallets, protecting users whose login details are compromised. Moreover, they are completely free and as simple as email – on both desktop and mobile!
This new system represents the future of crypto funds management: secure, convenient, free and accessible to anyone.
You can stay up to date with Nash by following our Twitter and Instagram, as well as joining our official Telegram group. We also encourage all Nash Exchange token (NEX) holders to join our community platform, where they can talk directly with the team and receive reliable answers to questions.