Patent ID: 7266695
Filing Date: 2007-09-04
Classification: G06F,G06Q,G07F

Abstract:
1. A data updating method comprising steps of: storing a first secret key used for device authentication and a first common key or public key used for issuer authentication in a device; outputting an issuer authenticator encrypted by the first common key or public key from the device to a client computer; outputting a device authenticator encrypted by using the first secret key from the device to the client computer, decrypting the encrypted update data inputted from the client computer by the first secret key and updating data therein based on the decrypted update data; transmitting the encrypted issuer authenticator in the client computer to a server, transmitting the encrypted device authenticator inputted from the device to the server, receiving the encrypted update data transmitted from the server and outputting the encrypted update data to the device; storing a second common key or a second secret key used for the issuer authentication in the server, decrypting the encrypted issuer authenticator received from the client computer by the stored second common or secret key, obtaining an issuer identifier, comparing and collating the obtained issuer identifier with a stored issuer identifier, performing issuer server authentication, decrypting the encrypted device authenticator received from the client computer by a second public key corresponding to the device authenticator, obtaining a device identifier, comparing and collating the obtained device identifier with a stored device identifier, performing the device authentication, and transmitting the update data encrypted by using the second public key corresponding to the first secret key to the client computer, wherein said issuer authenticator and issuer identifier are unique to identify an issuer of the device, and said device authenticator and device identifier are unique to identify the device.