EP0246823A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Data communication systems and methods
Assignee: Racal Guardata Financial Systems Ltd
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Filing: 1987-05-15
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Granted: —
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Expires: 2007-05-15
Abstract
Abstract In order to improve the security of message transmission from a terminal apparatus 1 in a communications system a check-sum or MAC is computed from the data within the message in dependence upon a cryptographic key (KEY 1). This MAC is issued as a "challenge" to a user who is also equipped with a separate portable token 2 for computing a "response" in dependence upon a second cryptographic key (KEY 2) which is unique to his token. This "response" is then entered into the terminal 1 and appended to the message as its authentication code before transmission. A recipient of the message and authentication code equipped with the same cryptographic keys can therefore check both the contents of the message and the correct identity of the sender by computing an expected authentication code from the received message and comparing it with the code received.
Inventors
- 👤 Henry Joseph Beker
- 👤 Paul William Halliden
- 👤 John Michael Kenneth Friend
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 21:43
CPC Classifications
G; G07; G07F; G07F7/00; G07F7/08; G07F7/10; G07F7/1008; G06; G06Q; G06Q20/00; G06Q20/30; G06Q20/34; G06Q20/341; G06Q20/36; G06Q20/367; G06Q20/3674; G06Q20/38; G06Q20/40; G06Q20/401; G06Q20/4012; G06Q20/409; G06Q20/4097; G06Q20/40975; H; H04; H04L; H04L9/00; H04L9/32; H04L9/3226; H04L9/3231; H04L9/3234; H04L9/3236; H04L9/3242; H04L9/3271; H04L2209/00; H04L2209/56
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
160 words
A method of secure message transmission from a terminal apparatus (1) to a remote receiving station in a communications system, which involves appending to a message to be transmitted an authentication code the value of which depends upon both the information in the message and information representing the identity of the sender, characterized in that the authentication code is produced by a method comprising the steps of: computing within the terminal apparatus (1) a first code the value of which depends upon the information within the message; issuing that code to the sender; computing a second code from said first code and information representing the identity of the sender, within a token (2) assigned to the sender and which can be actuated to perform this computation only upon recognition of a correct input indicative of the authority of the sender; and entering said second code into the terminal apparatus (1), that code or a derivative thereof constituting the authentication code.
Claim 2
Independent Claim
160 words
A method of secure message transmission from a terminal apparatus (1) to a remote receiving station in a communications system, which involves appending to a message to be transmitted an authentication code the value of which depends upon both the information in the message and information representing the identity of the sender, characterized in that the authentication code is produced by a method comprising the steps of: computing within the terminal apparatus (1) a first code the value of which depends upon the information within the message; issuing that code to the sender; computing a second code from said first code and information representing the identity of the sender, within a token (2) assigned to the sender and which can be actuated to perform this computation only upon recognition of a correct input indicative of the authority of the sender; and entering said second code into the terminal apparatus (1), that code or a derivative thereof constituting the authentication code.
Claim 3
Dependent Claim
34 words
A method according to claim 1 wherein the computation of said first and second codes is dependent upon respective cryptographic keys (KEY l; KEY 2) held in the terminal apparatus (1) and token (2).
Claim 4
Dependent Claim
36 words
A method according to claim 2 wherein the cryptographic key (KEY 2) held in the token (2) is unique for each individual token (2) in the system and thus represents the identity of the corresponding sender.
Claim 5
Independent Claim
24 words
A method according to any preceding claim wherein the token (2) is portable and in use completely structually separate from the terminal apparatus (1).
Claim 6
Independent Claim
35 words
A method according to any preceding claim wherein the token (2) can be activated to perform the computation of said second code upon the recognition of a correct sender's personal identification number inputted to it.
Claim 7
Dependent Claim
38 words
A method according to any one of claim 1 to 4 wherein the token (2) can be activated to perform the computation of said second code upon the recognition of a correct sender's biometric parameter inputted to it.
Claim 8
Independent Claim
20 words
A method according to any preceding claim wherein said first code is also appended to the message to be transmitted.
Claim 9
Dependent Claim
157 words
Apparatus for secure message transmission to a remote receiving station in a communications system, by a method which involves appending to a message to be transmitted an authentication code the value of which depends upon both the information in the message and information representing the identity of the sender, characterized by a terminal apparatus (1) adapted to compute a first code the value of which depends upon the information within the message and to issue that code to the sender; and a token (2) assigned to the sender which is adapted to compute a second code from said first code and information representing the identity of the sender and which can be activated to perform this computation only upon recognition of a correct input indicative of the authority of the-sender; the terminal apparatus (1) also being adapted to receive said second code and append that code or a derivative thereof to the message as said authentication code.
Claim 10
Dependent Claim
157 words
Apparatus for secure message transmission to a remote receiving station in a communications system, by a method which involves appending to a message to be transmitted an authentication code the value of which depends upon both the information in the message and information representing the identity of the sender, characterized by a terminal apparatus (1) adapted to compute a first code the value of which depends upon the information within the message and to issue that code to the sender; and a token (2) assigned to the sender which is adapted to compute a second code from said first code and information representing the identity of the sender and which can be activated to perform this computation only upon recognition of a correct input indicative of the authority of the-sender; the terminal apparatus (1) also being adapted to receive said second code and append that code or a derivative thereof to the message as said authentication code.
Claim 11
Dependent Claim
19 words
Apparatus according to claim 8 and adapted to perform the method of any one of claims 2 to 7.
References Cited (Backward Citations)
No citation records indexed.
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