Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
195 words
A communication system comprising a first communication terminal (11 1 ...11 n ) and a second communication terminal (12) coupled to each other through a communication line (13,...13 ); first and second integrated circuit devices (14 1 ...14 n ; 15) having semiconductor large scale integrated circuits sealed therein and operatively coupled to said first and second communication terminals (11 1 ...11 n ; 12), respectively, said first integrated circuit device (14 1 ...14 n ) having at least a function for enciphering a first kind of messages (M) entered from said first communication terminal, said second integrated circuit device (15) having at least a function for deciphering the enciphered first kind of messages (C) entered from said second communication terminal, and the enciphered first kind of messages (C) being sent from said first communication terminal to said second communication terminal through said communication line, characterized in that said first integrated circuit device (14) comprises recording means (33), and is arranged to automatically record the first kind of messages (M) to be sent to said second communication terminal in an area (V) of said recording means which can be accessed from outside only for readout.
Claim 2
Dependent Claim
195 words
A communication system comprising a first communication terminal (11 1 ...11 n ) and a second communication terminal (12) coupled to each other through a communication line (13,...13 ); first and second integrated circuit devices (14 1 ...14 n ; 15) having semiconductor large scale integrated circuits sealed therein and operatively coupled to said first and second communication terminals (11 1 ...11 n ; 12), respectively, said first integrated circuit device (14 1 ...14 n ) having at least a function for enciphering a first kind of messages (M) entered from said first communication terminal, said second integrated circuit device (15) having at least a function for deciphering the enciphered first kind of messages (C) entered from said second communication terminal, and the enciphered first kind of messages (C) being sent from said first communication terminal to said second communication terminal through said communication line, characterized in that said first integrated circuit device (14) comprises recording means (33), and is arranged to automatically record the first kind of messages (M) to be sent to said second communication terminal in an area (V) of said recording means which can be accessed from outside only for readout.
Claim 3
Dependent Claim
131 words
A system according to claim 1, characterized in that said second integrated circuit device (15) has a function for enciphering a second kind of messages (M') which are entered from said second communication terminal (12) and which are to be transmitted as response messages to the first kind of messages to said first communication terminal, and said first integrated circuit device has a function for deciphering the second kind of enciphered messages (C') which are sent from said second communication terminal to said first communication terminal and entered from said first communication terminal and is arranged to automatically record the deciphered second kind of messages (M'), in association with decryption of the enciphered second kind of messages, in the area (V) of said recording means in said first integrated circuit device.
Claim 4
Dependent Claim
58 words
A system according to claim 2, characterized in that said first integrated circuit device (14) is arranged to record the first and second kinds of messages (M, M') in the area (V) in said recording device (33) in a form such that the first kind of messages and second kind of messages can be distinguished from each other.
Claim 5
Dependent Claim
34 words
A system according to claim 3, characterized in that the first and second kinds of messages (M, M') are recorded in first and second sub-areas of the area (V) in said recording means (33).
Claim 6
Dependent Claim
32 words
A system according to claim 3, characterized in that the first and second kinds of messages (M, M') are recorded together with encryption/decryption distinction data in the area in said recording device.
Claim 7
Dependent Claim
146 words
A system according to claim 2, characterized in that said first integrated circuit device (14) has a decryption function, said second integrated circuit device (15) has an encryption function; said second communication terminal inputs to said second integrated circuit device the second kind of messages (M') as a response to the first kind of messages (M) from said first communication terminal (11); said second integrated circuit device enciphers the second kind of messages; said first communication terminal inputs the enciphered second kind of messages sent from said second communication terminal to said first integrated circuit device for decryption thereof; said first integrated circuit device (14) outputs the deciphered second kind of messages (M') to said first communication terminal (11); and said first communication terminal sends back the second kind of messages to said second terminal (12) when the deciphered second kind of messages (M') are acceptable.
Claim 8
Dependent Claim
122 words
A system according to claim 2, characterized in that said first and second integrated circuit devices (14; 15) have decryption and encryption functions, respectively; said second communication terminal (12) inputs to said second integrated circuit device a second kind of messages having authentication data (RN) and a response message (M') in response to reception of the first kind of messages (M) from said first communication terminal (11); said second integrated circuit device enciphers the second kind of messages; said first communication terminal inputs to said first integrated circuit device the enciphered second kind of messages (C') sent from said second communication terminal; and the deciphered second kind of messages are output from said first integrated circuit device to said first communication terminal.
Claim 9
Dependent Claim
82 words
A system according to claim 7, characterized in that said first communication terminal (11) extracts the authentication data (RN) from the deciphered second kind of messages and sends back the authentication data (RN) to said second communication terminal (12), and said second communication terminal compares the transmitted authentication data with the received authentication data, so that a determination is made as to whether the enciphered second kind of messages (C') are properly deciphered and recorded in said first integrated circuit device (14).
Claim 10
Dependent Claim
33 words
A system according to claim 7, characterized in that the deciphered second kind of messages are recorded in the area (V) of said recording device (33) in said first integrated circuit device (14).
Claim 11
Dependent Claim
22 words
A system according to claim 7, characterized in that the authentication data is random number data generated in said second communication terminal.
Claim 12
Dependent Claim
198 words
A system according to claim 1, characterized in that said first integrated circuit device (14) has a decryption function; said second integrated circuit device (15) has an encryption function; said first communication terminal (11) inputs to said first integrated circuit device the first kind of messages having a transmission kind of messages (M) and first authentication data (R'N) so that the first kind of messages are enciphered, and the enciphered first kind of messages (C) are output to said first communication terminal (11) to be transmitted to said second communication terminal (12); the enciphered first kind of messages are deciphered by said second integrated circuit device (15); said second integrated circuit device enciphers the second kind of messages having response message (M') and first authentication data (RN), the enciphered second kind of messages (C') are sent to said first communication terminal to be deciphered by said first integrated circuit device, and said first communication terminal compares the first authentication data sent to said second communication terminal with the first authentication data sent back from said second communication terminal, thereby determining as to whether the first kind of messages have been properly deciphered by said second integrated circuit device.