To provide a communication system capable of easily recovering a faulty state to a state wherein normal authentication can be carried out even when the authentication is failed while maintaining the security.
A communication apparatus provided with a communication means and authenticating a communication party by using a digital certificate in communication, uses a rescue public key certificate being a digital certificate issued by a private certificate authority to authenticate the communication party (S107), and acquires a regular public key certificate being a digital certificate issued by a public certificate authority when the authentication using the rescue public key certificate is successful and transmits the regular public key certificate to the communication party (S111). In this case, when the communication apparatus requests the communication party to make communication, the communication apparatus first uses the regular public key certificate to authenticate the communication party (S103) and it is better to make authentication using the rescue public key certificate when the authentication using the regular public key certificate is failed.
COPYRIGHT: (C)2005,JPO&NCIPI
| JP2002287631A | ||||
| JP2005333597A | ||||
| JP2006048653A | ||||
| JP2005130449A | ||||
| JP2005130458A | ||||
| JP3162152A |
| US5781723 | ||||
| WO2000079724A1 |
Kei Osawa