An operator console for data communication purposes

Abstract: An operator console for data communication includes a keyboard and a ciphering deciphering/unit. The console is divided into two separate units which can be connected electrically together, namely a keyboard (10) and a security module (11). The keyboard (10) includes keys (101), logical unit (21) with memory (211) and a ciphering/deciphering circuit (22). The securing module (11) includes a logical unit (31) having a memory (311), a ciphering/deciphering cir­ cuit (32), and a random generator (34) which, in conjunc­ tion with keyboard communication, randomly generates a code necessary to effect the communication and transfers this code to the keyboard memory (211) and replaces a code previously stored therein. Connected between the input side of the keyboard (10) and the memory (211) is a security circuit which disconnects a conduit (240) to the keyboard memory (211), subsequent to a first transfer of a code from the security module (11), and connects instead a further conductor (241) to the memory (211) over the ciphering/deciphering circuit (22).

Description: TECHNICAL FIELD The present invention relates to an operator console for data communication purposes and of the kind set forth in the preamble of claim 1. An apparatus for identity control and incorporating the features of said preamble is previously disclosed in EP-A2-0 063 794. BACKGROUND TO PRIOR ART Operator consoles intended, for example, for customer operated cash dispensers with which a customer identifies himself as being authorized to withdraw a given sum of money, by presenting an appropriate card are known to the art. The dispenser receives, via the card, information stored in a magnetic medium in the card (customer data) and also, through the keybank, information concerning the personal code of the customer (PIN-code). The customer data and PIN-code are evaluated in the logical unit of the dispenser and the result of this evaluation is decisive of whether or not the customer is entitled to receive cash through the dispenser. There is a general risk with such systems that unauthorized knowledge of the evaluation of customer data and PIN-code can be used to unlawful ends. In known consoles of this kind the keybank and logical unit, which incorporates the necessary algorithms and codes (ciphers) for carrying out the evaluation, are combined to form a single unit which, in order to be accessible to customers, is placed in an open location and not, as would be desirable from the aspect of safety, in a safety box. Consoles of the aforesaid kind may suffer one or more of the following drawbacks: 1. The console is equipped with a protective device which cuts-off the supply voltage in the event of a forced entry (burglary) but does not destroy the content of the memory in the logical unit. 2. The logical unit is not protected, by being located in a safety box or cabinet. 3. It is possible to intercept, or "eaves-drop" on PIN-codes sent from the keybank to the logical unit. 4. Requisite programmes and codes are incorporated during manufacture Of the console, which places high security demands on the prevention of unauthorized acquisition of manufacturing data, in order not to render the system vulnerable. The object of the invention is to eliminate these drawbacks and similar disadvantages. SUMMARY OF THE INVENTION In accordance with the invention, as claimed in claim 1, an operator console of the aforesaid kind is divided into two separate units capable of being electrically connected one to the other, namely a keybank and a safety module which incorporates a logical unit provided with a memory for programmes and codes and a random generator for generating at random the codes necessary to effect communication between the keybank and the safety module. This enables the keybank to be placed in an external location where it is readily accessible to the customer, and the safety module to be placed in a burglar-proof safety cabinet or box. The random generation of codes (master code) means that the manufacturing process need not be encumbered with rigorous security conditions. Subsequent to pairing together a button bank and a safety module and generating a master code necessary for co-action therebetween, there is obtained an operator console with parts which can communicate solely with one another. No known keybank master code exists in the system. If either the keybank or the safety module should become unserviceable, e.g. as a result of being physically forced, it is necessary to pair together two new units, to form a complete operator console. These and other characteristic features of the invention will be apparent from the following description. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying schematic drawings, in which Figure 1 is a block schematic illustrating an operator module equipped with keybank and safety module; Figure 2 is a more detailed illustration of the keybank shown in Figure 1; Figure 3 is a more detailed illustration of the safety module shown in Figure 1; and Figure 4 illustrates a group of keys or buttons on the keybank shown in Figure 2. DESCRIPTION OF A PREFERRED EMBODIMENT The operator console 10-11-12 illustrated schematically in Figure 1 comprises two separate units which are capable of being coupled electrically one to the other, namely a keybank 10 and a safety module 11. The two units are coupled one to another via a transfer-monitoring circuit 12 which contains, inter alia, a main control programme for the whole of the automatics in the system, and also adapter circuits for signal conversion, when required. The safety module 11 and the circuit 12 are intended to be placed in a security cabinet or box, whereas the keyboard is placed in a location where it is freely accessible to, e.g., bank customers. As illustrated in Figure 2, the keyboard 10 includes a multiple of keys or buttons 101, an input circuit 20, a logical unit 21 with memory circuit 211, an enciphering/deciphering circuit 22 and a security circuit 24 having a first conductor 240 and a second conductor 241 (dotted line). The security circuit 24 is constructed to disconnect the circuit conduit 240 and to connect, instead the conductor 241 immediately subsequent to a first transfer of a code (master code) from the security module 11. As shown in Figure 3, the security module 11 includes a logical unit 31 incorporating a memory circuit 311, an enciphering/deciphering circuit 32, an evaluating circuit 33 and a random generator 34 for randomly generating a code necessary for communication between the keyboard 10 and the security module 11. During the manufacture of the keyboard 10, an "initial" master code is fed into the memory 211. The security circuit 24 is then activated, i.e. the conductor 240 is disconnected and the conductor 241 connected. This means that no new master code can be fed into the memory 211, without prior knowledge of the "initial" master code. The keyboard 10 programmed with an "initial" master code is paired together with a security module 11, the random generator 34 of which is caused, upon command, to generate a randomly selected master code. This master code, which is unknown per se, is transferred with the aid of the known "initial" master code to the memory circuit 211 of the keyboard 10, where it replaces the "initial" master code. The new master code, which is known solely by the security module and the keyboard, is necessary for continued communication, between the two units. It is important that no "eaves dropping" can take place when pairing a keyboard with a security module, and that verification is obtained of the fact that the new (unknown) master code has actually been stored in the memory 211. Such verification is obtained by testing the communication between the units. Correct functioning of the communication in the intended manner is a verification of the fact that the new master code has been received. If communication does not function correctly, a new master code is transferred with the aid of the "initial" master code, this "initial" master code being known by the manufacturer and in probability is present in the memory circuit 211. Normally, communication between the security module 11 and the keyboard 10 is established with the aid of a working code initially generated in the security module. The working code is changed in accordance with a given algorithm and is ciphered under the master code. The working code undergoes the algorithm for each message, and the changed working code can be ciphered/deciphered under the old working code. This reduces the risk of the master code being stolen by some unauthorized person. The working code can be changed at suitable times (thus not only changed by the algorithm), newly created by the security module, and then ciphered under either the master code or under the old, changed working code for communication with the keyboard 10. A new master code can be generated and, together with the order "change code", communicated from the security module 11 in accordance with a programme inserted into the transfer - and - monitoring circuit 12. the new master code is then ciphered under the old master code. As before mentioned, information between the security module 11 and the keyboard 10 is carried by the circuit 12, which in accordance with its main programme does not change the contents of the message, but merely acts as a communication intermediary between the units. A normal working cycle begins with an order to the keyboard 10 to read in a number of characters (e.g. from an inserted card and from the PIN-code entered on the keybank 101.) When the characters have been collected, ciphering is effected in the circuit 22 in accordance with an existing working code, and information is transmitted to the security module 11. Subsequent to the working code having been used once in this way, the code passes the algorithm and is changed thereby. The security module 11 receives the ciphered characters and deciphers the same in the circuit 32 under the prevailing working code. The transmitted character message is evaluated in the evaluating circuit 33 (authorized or not-authorized), and the working code passes the algorithm (the same algorithm as that in the keyboard 10) and is changed therewith. The two units now have the same changed working code stored in their logical units. In order to further protect the operator console against unauthorized "eaves-dropping", the keys 101 of the keyboard 10 (see Figure 4) are provided with magnets 1011 which are arranged to activate individually associated magnetic sensors 1012, when the keys are activated externally. This will further safeguard the PIN-code during the transmission between respective keys and the keyboard in general. The keyboard 10 is also equipped with a sensing circuit which, when sensing forced entry into the keyboard 10 (burglary), is intended to initiate an erasure process (or over-write) to erase (over-write) programmes and information stored in the logical unit 21 and the memory circuit 211 of the keyboard. This affords an additional safeguard for the master code and working code. An operator console constructed in accordance with the invention affords the following advantages. 1. The security module 11 can be placed in a security cabinet while the keyboard 10 is located in a position where it is readily accessible to the user. Security is enhanced in this way. 2. Un authorized eaves-dropping of the PIN-code is made extremely difficult. 3. Communication between keyboard 10 and security module 11 is effected with codes which are known solely by these two mutually co-acting units. 4. Keyboards 10 can be produced with known software, card layout and initial code without jeopardizing security. This enables keyboards to be manufactured at lower cost. 5. The combination of a keyboard 10 and a security module 11 to form an inseparable, co-acting pair of units enhances security. 6. The master code and working code in the keyboard 10 are supervised by an active anti-burglary device which when an attempt is made to forcibly enter the keyboard, will destroy the contents of the logical unit and the memory of the keyboard 10. 7. The possibility is found of resetting the keyboard 10 to its initial state, subsequent to changing the "initial" master code. 8. By using an automatically changing working code in the process of communication between keyboard and security module, unnecessary exposure of the master code which couples the units together for transmission purposes is avoided. The aforementioned sensing circuit suitably comprises a winding, wound in closely adjacent turns (insulated) around the entire keyboard, with the exception of the uppermost parts of the keys. When the console is operative, the winding carries a weak current, and in the event of a break or fracture in the winding (e.g. caused by an attempt to break into the keyboard) the current is interrupted and the erasure process initiated therewith. The sensing circuit can be made more effective by dividing the circuit into two part-windings connected in series and wound around the keyboard in two directions essentially at right angles to one another. It is extremely important to obtain an effective guard between the upper, outer touch-surfaces of the keys and the remainder of the keyboard. This can be achieved in practice, e.g., in the following manner. The various components of the keyboard (logic components, sensors, battery, fuses) are mounted on two circuit cards, which are then positioned parallel with one another with the components facing one another. This circuit-card combination is then wrapped in a layer of shrink plastics, whereafter the winding (part-winding) is (are) wound around the plastics layer. A layer of molten plastics is then applied, and finally a further layer of shrink plastics.

Claims: An operator console for data communication, comprising a keyboard, a logical unit and a ciphering/deciphering unit, wherein the console is divided into two separate units capable of being electrically coupled together, namely a keyboard (10) and a security module (11), wherein the keyboard (10) includes a multiple of keys (101), a logical unit (21) which incorporates a memory circuit (211), and a ciphering/deciphering circuit (22), and wherein the security module (11) includes a logical unit (31) which incorporates a memory (311), and a ciphering/deciphering circuit (32), a random generator (34) being arranged for randomly generating a code necessary for effecting communication between the keyboard (10) and the security module (11), characterized in that said generator (34) is located in the security module (11) and is intended, in conjunction with communication with the keyboard (10), to randomly generate a code and to transfer the code to the memory circuit (211) of the keyboard (10) and there replace a previously stored code, and further characterized by a security circuit (24) which is connected between the input side of the keyboard (10) and the memory circuit (211) and which is intended to disconnect a conductor (240) passing to the memory circuit (211) immediately subsequent to a first code transfer from the security module (11) and to connect instead a further conductor (241) to the memory circuit (211) over the ciphering/deciphering circuit (22). An operator console according to claim 1, characterized by a keyboard monitoring sensor-circuit which, when sensing a forced entry into the keyboard, is intended to initiate an erasure process for erasing the programme and information contained in the logical unit (21) and the memory circuit (211) of the keyboard (10). An operator console according to claim 2, characterized in that the sensing circuit includes a winding which embraces the entire keyboard with the exception of the uppermost touch-surfaces of the keys (101), and which is intended to initiate said erasure process upon the occurrence of a break or fracture in said winding. An operator console according to claim 3, characterized in that the winding is divided into two series-connected part-windings which are wound around the keyboard in two mutually perpendicular directions, or at least substantially perpendicular directions. An operator console according to claim 4, characterized in that the keys (101) of the keyboard (10) are provided with magnets (1011) which, when the keys are touched externally, activate magnetic sensors (1012) which are individual to each of the keys and which are located within the winding.

Inventors: WIGUR JAN, WIGUR, JAN
Applicants: INTER INNOVATION AB, DE LA RUE INTER INNOVATION AKTIEBOLAG
Application year: 1987
Main classification: H04L9
IPC codes: G06F21, G07F7, G06F3, G06F1