A Proposal of a Password Manager Satisfying Security and Usability by Using the Secret Sharing and a Personal Server

Password managers protect users' passwords by using a master password or a security token. The security of them using the master password is weakened if users use weak master passwords. The usability of them using the security token is low since users always need the token to log in. In this paper, we propose a new framework of password managers which has a high security and a high usability by employing the secret sharing and a personal servers for a user.