Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
106 words
An IC card for connection to an information processing apparatus, comprising: a clock for counting time; ID storage means for storing a permanent ID; information storage means for storing a changeable password to identify said IC card when said IC card is connected to said information processing apparatus; procedure storage means for storing a changeable ciphering program for encrypting said password; and control means for encrypting said password in accordance with said ciphering program stored in said procedure storage means and outputting the encrypted password to a connected information processing apparatus in response to a request for such encrypted password from the connected information processing apparatus.
Claim 2
Dependent Claim
106 words
An IC card for connection to an information processing apparatus, comprising: a clock for counting time; ID storage means for storing a permanent ID; information storage means for storing a changeable password to identify said IC card when said IC card is connected to said information processing apparatus; procedure storage means for storing a changeable ciphering program for encrypting said password; and control means for encrypting said password in accordance with said ciphering program stored in said procedure storage means and outputting the encrypted password to a connected information processing apparatus in response to a request for such encrypted password from the connected information processing apparatus.
Claim 3
Dependent Claim
153 words
An authentication method, for an information processing apparatus, which employs the IC card defined in claim 1 to authenticate a mutual connection between said IC card and said information processing apparatus, in which said password is registered in advance, comprising the steps of: transmitting the password and the ciphering program from said information processing apparatus to said IC card; storing the password and the ciphering program by said IC card; reading a time count of said clock; encrypting the time count, the password, and the ID in accordance with the stored ciphering program to produce encrypted information; transmitting the encrypted information to said information processing apparatus; and deciphering the received encrypted information in accordance with a deciphering program that corresponds to the ciphering program to produce a deciphered password, and authenticating the connection between said IC card and said information processing apparatus only when the deciphered password matches the password registered in advance.
Claim 4
Dependent Claim
44 words
The authentication method for an information processing apparatus according to claim 2, wherein the password and the ciphering program are altered in accordance with instructions from said IC card issued at periodic intervals that are based on the time count performed by said clock.
Claim 5
Dependent Claim
19 words
The IC card according to claim 1, further comprising a keyboard on the IC card for updating the password.
Claim 6
Dependent Claim
16 words
The IC card as in claim 4, further comprising a display mounted on the IC card.
Claim 7
Dependent Claim
16 words
The IC card as in claim 1, further comprising a display mounted on the IC card.