Patent ID: 7124436
Filing Date: 2006-10-17
Classification: G06F,G11B,G11C,H04K

Abstract:
1. A data processing method performed between an external device and a data processing apparatus, the method comprising the steps of: generating a first random number and sending the first random number and identification data of the external device to said data processing apparatus, receiving the first random number and the identification data, generating an authentication key by encrypting the identification data with a master key stored in the data processing apparatus, generating a second random number and creating a first authentication code with the authentication key by encrypting a combination of the first random number, the second random number, and the identification data with the authentication key, generating a third random number and sending a combination of the second random number, the third random number, the first authentication code, and a master key number to the external device, receiving the combination of the second random number, the third random number, the first authentication code, and the master key number from the data processing apparatus; finding the authentication key from the master key number; and calculating a second authentication code with the authentication key using the combination of the second random number, the first random number, and the identification data.