METHOD AND SYSTEM FOR CONTROLLING KEY FOR ELECTRONIC SIGNATURE

摘要

Two keys which are changed in the same updating cycle at different times are prepared as signature keys (main key and auxiliary key) for electronic signature and the updating cycle of each key is divided into, for example, three periods. Electronic signature is executed with the main key by using the first and last periods right after the change for the auxiliary key and the intermediate period for the main key. The electronic signature is confirmed by using either of the two confirmation keys which are changed synchronously with the change of the two keys used as the signature keys. Thus, the need of stopping the issuance of electronic signature or limiting provided service at the time of updating the signature keys is eliminated.