Forward Secure Password-Enabled PKI with Instant Revocation

摘要

Recently the concept of password-enabled PKI is an emerging issue to support user mobility. Virtual soft token and virtual smart-card were proposed as the password-enabled PKI. However, the virtual soft token does not support key disabling. In the virtual smartcard, the user must interact with remote entity per signing operation. In addition, both schemes do not support forward secrecy and instant revocation. In this paper, we propose a new approach that supports user mobility. The proposed approach supports key disabling and the user does not need interaction with the remote entity for each signature. Moreover, the proposed scheme allows instant key revocation. Thereby, the distribution of CRL is not required. Furthermore, the proposed scheme supports forward secrecy. In this sense, our scheme, implemented only software, is stronger than a long-term private key with physical smart cards. By forward secrecy and instant revocation, signing documents using a time-stamp provided by a trusted authority is not required to protect from modifying signed document by the adversary who knows private key.