Self-Custodial Wallet Key Sharding for Secure Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-custodial digital wallet users face a challenge in balancing the security and accessibility of their private keys, as losing the seed phrase results in irreversible access loss, with existing solutions lacking recovery mechanisms and secure storage methods.
Innovation Solution
A self-custodial digital wallet that splits the private key into shards, using Shamir Secret Sharing, and securely stores them across various secure storage points accessible via biometrics, two-factor authentication, and social media accounts, allowing for recovery with a minimum number of shards, ensuring the private key only exists briefly during transactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the private key is stored in a single secure location, then security is improved, but accessibility and recovery capability deteriorate
Solution Approach 1:
The patent divides the private key into multiple shards using Shamir Secret Sharing algorithm. These shards are distributed across different secure storage locations (device storage, cloud storage, hardware security modules). No single location contains the complete private key, providing both security and redundancy. If one storage location is compromised or lost, the private key can still be recovered by combining sufficient shards from other locations.
2Reliability
If the seed phrase is hidden and protected, then security is improved, but the risk of permanent loss increases
Solution Approach 1:
The patent implements recovery mechanisms by creating multiple copies of key shards and storing them in different secure locations before any loss occurs. This cushioning approach ensures that if the user loses their device or forgets their password, the private key can still be recovered by reconstructing it from distributed shards, preventing permanent loss while maintaining security.
3Ease of operation
If the private key is distributed across multiple storage points, then recovery capability is improved, but security against compromise deteriorates
Solution Approach 1:
The patent uses Shamir Secret Sharing to divide the private key into shards such that a threshold number of shards are required to reconstruct the key. This segmentation ensures that even if some storage points are compromised, the private key remains secure as long as the number of compromised points does not reach the threshold. Simultaneously, the distributed nature enables recovery if some points are lost.
Solution Approach 2:
Different shards are stored with different security characteristics in different locations. Some shards may be stored in hardware security modules with high physical security, others in encrypted cloud storage with access control. Each storage location has optimized security properties appropriate to its environment, providing both security and recovery capability.
Data Source
AI summary
A method for securing a split private key (such as used with a cryptocurrency or other non-custodial electronic wallet) amongst a password, biometrics, and a social service. The process may use a sharding scheme such as Shamir's Secret Sharing to ensure that multiple key shards must be obtained before the entire private key can be obtained. The user may select the number of shards required to retrieve the private key thereby controlling the security of the account. An additional shard may be held on an encrypted server and allows for account recovery even while maintaining non-custodial ownership of the wallet.