TY - EJOU AU - Ra, Gyeong-Jin AU - Roh, Chang-Hyun AU - Lee, Im-Yeong TI - A Key Recovery System Based on Password-Protected Secret Sharing in a Permissioned Blockchain T2 - Computers, Materials \& Continua PY - 2020 VL - 65 IS - 1 SN - 1546-2226 AB - In today’s fourth industrial revolution, various blockchain technologies are being actively researched. A blockchain is a peer-to-peer data-sharing structure lacking central control. If a user wishes to access stored data, she/he must employ a private key to prove ownership of the data and create a transaction. If the private key is lost, blockchain data cannot be accessed. To solve such a problem, public blockchain users can recover the key using a wallet program. However, key recovery in a permissioned blockchain (PBC) has been but little studied. The PBC server is Honest-but-Curious (HBC), and should not be able to learn anything of the user; the server should simply recover and store the key. The server must also be resistant to malicious attacks. Therefore, key recovery in a PBC must satisfy various security requirements. Here, we present a password-protected secret sharing (PPSS) key recovery system, protected by a secure password from a malicious key storage server of a PBC. We describe existing key recovery schemes and our PPSS scheme. KW - Password-protected secret sharing KW - key recovery KW - blockchain KW - wallet security DO - 10.32604/cmc.2020.011293