Research on Wallet Protection Against Currency Failure in Blockchain

Abstract

The protection of blockchain wallet is the basis of secure transaction in blockchain. Private key is the core of wallet security. The private key cannot be protected based on a reliable third party. Therefore, the loss or theft of private key will lead to the loss of customer property. To solve this problem, a distributed protection and recovery mechanism is proposed. Every wallet private key is divided into multiple key fragments by threshold key mechanism according to the network scale. Even if the wallet is offline, the threshold number of holders holding key fragements from the wallet cooperates to distribute key fragments to new members, which keeps the update of key fragments synchronized. When the key is lost, the number of private key fragments exceeding the threshold of half the blockchain member scale can ensure the recovery of the private key. The dynamic threshold mechanism design makes the attacker must attack more than half of the members to steal the wallet private key successfully. The hash based shard key tree can quickly detect the number of key fragments smaller than the specified size, the invalid key fragments are detected and eliminated efficiently in the network, and the integrity of the global private key is guaranteed. The suggested method of wallet protection is feasible from the aspect of secure storage.

Keywords

• blockchain
• wallet
• threshold cryptography
• distributed storage
• security