Private key encryption and recovery in blockchain
This addresses key management bottlenecks for blockchain users, offering a practical solution to enhance security and usability, though it appears incremental by building on existing biometric and secret sharing techniques.
The paper tackles the problem of secure storage and recovery of private keys in blockchain by proposing an encryption method using biometric signatures and a recovery mechanism combining biometrics with secret sharing, enabling asset owners to securely store keys on devices and recover them if lost.
The disruptive technology of blockchain can deliver secure solutions without the need for a central authority. In blockchain protocols, assets that belong to a participant are controlled through the private key of an asymmetric key pair that is owned by the participant. Although, this lets blockchain network participants to have sovereignty on their assets, it comes with the responsibility of managing their own keys. Currently, there exists two major bottlenecks in managing keys; $a)$ users don't have an efficient and secure way to store their keys, $b)$ no efficient recovery mechanism exists in case the keys are lost. In this study, we propose secure methods to efficiently store and recover keys. For the first, we introduce an efficient encryption mechanism to securely encrypt and decrypt the private key using the owner's biometric signature. For the later, we introduce an efficient recovery mechanism using biometrics and secret sharing scheme. By applying the proposed key encryption and recovery mechanism, asset owners are able to securely store their keys on their devices and recover the keys in case they are lost.