By means of the certificate-checking method,the whole system designs a certificate center that issues X. 509 certificate and manages the certificate through light directory access protocol (LDAP).是什么意思_By means of the certificate-checking method,the whole system designs a certificate center that issues X. 509 certificate and manages the certificate through light directory access protocol (LDAP).在线翻译_英语_读音_用法_例句