FI104922B - Hardware for detecting fraud attempts on a device to read and write a smart card - Google Patents

Description

, 104922

Hardware for detecting fraud attempts on a device to read and write a smart card

The invention relates to apparatus of the type mentioned in the preamble of claim 1 for detecting attempted fraud in a device for reading and writing a chip card.

Such devices are advantageously used in service systems - for example, self-financing telephone 10 stations (Payphone), which operate with electronic chip cards.

A fraudulent attempt uses a modified chip card or similar card having similarly located access points, wherein at least one of the access points 15 is connected to an electrical input line of a non-writing device which is used to commit fraud. A fraud attempt can be detected when testing for such unauthorized cable.

An apparatus of the type mentioned in the preamble of claim 1 is known (EP 0 468 848 A1), wherein an inductive sensor and a selective filter coupled thereto are capable of detecting a signal from an input line of a card receiver, whereby a · · · /; It is advantageous to use known, standardized frequency * 1 signals when reading and writing a chip card.

***** It is also known to place a transmitter and a 1: 1: 30 receiver at one end of a chip card and a receiver at the other end of the card receiver and use any available input cable as a switching means, whereby the switching takes place on the transmission side. galvanically and inductively on the receiving side ···. (EP 0 323 347 A1, FR 2 554 262, FR 2 646 260) or capacitively (FR 2 646 260), or wherein the coupling operates close. 1 35 on the induction side and on the receiving side in- 1 2 · 104922 ductively (EP 0 447 686) or galvanically (EP 0 454 570).

Further, there is known an apparatus with an oscillator (FR 2 646 261) having a frequency determining part 5 which is moved over a chip card so that a possible input line causes interference with the output of the oscillator.

In the known equipment, mechanical devices such as antennas or movable sensors must be located in the chip card area within the card receiver such that they are well protected against damage.

The object of the invention is to provide a reliable and well protected apparatus for the detection of fraudulent attempts in the apparatus for reading and writing a smart card.

The invention consists of the features set forth in claim 1. Advantageous applications are found in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS Your embodiment of the invention will now be explained in greater detail by means of a drawing.

See: 20 Figure 1 hardware principle for detecting fraudulent attempts in hardware to read and write a chip card, Figure 2 hardware version with wire. , sonar, 25 Figure 3 hardware version of parallel resonance I (| circuit as resonator, '' Figure 4 hardware version with serial resonator circuit, ··· • Figure 5a hardware version in top design, Figure 30b Figure 5a hardware parts side view. FIG. 6 a hardware version with a conductor as at least two outputs as a resonator, FIG. 7 a complete circuit-35 diagram of the hardware version with the resonator of FIG. 6 and 104922 FIG. 8 of FIG. an example embodiment of a resonator.

In Fig. 1, reference numeral 1 denotes a resonator coupled to a contact chip 2 (Chipcard Reader / Writer) of a known device for reading and writing memory of a known chip card 3, which together with generator 4 and impedance transducer 5 forms a resonant unit 6. wherein the output of the generator 4 is connected via an impedance converter 5 to a resonator 1. The measuring apparatus 7 having an alarm output 8 of the alarm output 8 has at least one input connected to the resonance unit 6 and one output fed back to the resonance unit 6.

In addition to the contact portion 2, the apparatus for reading and writing the memory of the chip card 3 has other similar non-drawn contact portions, a processing unit 10 and a card receiver not shown in the drawing, which has a slot for the chip card 3. Each of the contact portions 20 is respectively connected by a power line 11 to a processing unit 10.

The chip card 3 is a value card having at least one electronic component, for example a microcomputer or memory, which can be accessed from a plurality of access points 25 12 by a read and write device having a contact portion 2 for each access point 12. the chip card 3 is standardized, and * there are various standards.

• · ·: 1. * It is known to use a predominantly · · · V 30 ti modified chip card 3 or similar card with fraudulent access points 12, j ***; wherein at least one of the access points 12 is connected f <t to the electrical input cable 13 of the device 14 outside the device. When a chip card is inserted into the device, an existing input cable 13 possibly connects to the corresponding input cable 13. The device 14 for fraudulent attempt is, for example, a measuring device or a simulator.

Apparatus for detecting attempted fraud by connecting the inlet lead 13 to the contact member 2 consists of a resonant unit 5 6, a measuring apparatus 7, a control member 9 and a shielding means 15 disposed between the resonant unit 6 and the wires 11; the details of the invention and their operation will be explained below.

The generator 4, whose output impedance to resonator 10 is determined by the impedance converter 5, generates in the resonator 1 an electromagnetic oscillation at a frequency of, for example, one GHz.

Preferably, the resonant unit 6 is adjusted such that at least a standing wave 15 is generated in the resonator 1 when the input line 13 at the connection point 12 connected to the resonator 1 via the contact portion 2 is missing. The input line 13 interferes with the properties of the resonator so that its input impedance and oscillation are measurably changed.

Preferably, as shown in Figure 2, the resonator 1 is an electrical conductor or waveguide formed in the form of a wire, a litch, a conductor, a current-conducting path, or a hollow body, and having at least one outlet A which. . is galvanically connected to the input of the measuring apparatus 7.

«T · 25 Outlet A is conveniently located near a standing wave node ··· ·.

t * 'The measuring apparatus 7, in the first ***** version of the apparatus, measures the electrical voltage of the output A and compares the measured value with the predetermined voltage value at the output A when the input line 13 is not connected to the contact section. 2. A fraud attempt is identified by a measure of value ···. and based on the magnitude of the difference in the holding value and generating an alarm signal, for example, at the output of a threshold switch belonging to the measuring apparatus 7.

<* • · · • · 5 104922

The measuring apparatus 7 preferably has processing means such as amplifiers or filters so that the measured value can be reliably understood.

Preferably, the processing unit 10 interprets the alarm signal 5 in a known manner.

The regulating element 9 enables the measurement value to be backfeeded to the generator 4 and / or the impedance converter 5 so that, if necessary, the frequency of the generator 4 and the output impedance of the impedance converter 5 can be changed from the measuring apparatus 7.

The shielding means 15 on the one hand shields the processing unit 10 from interference caused by the resonance unit 6 and on the other hand shields the apparatus from the interfering effects of the wires 11.

The second version preferably measures the voltage or impedance at the input of the resonator 1 and compares it to a predetermined holding value of the impedance or voltage. The holding value is the impedance of the resonator 1 or the voltage of the resonator 1 without the input line 13 in the contact portion 2.

20 The first and second versions can be seamlessly combined.

In the third version of the apparatus, the change in the generator 4 changes the frequency of the oscillation .. in the resonator 1 until the voltage at the output A reaches a certain target value. The target value is the same as the voltage • «« ·· 1 · | the value of the voltage at output A is equal to the vibration • 1 at the specified frequency hold value as long as the input line 13 is not connected to the contact portion 2. The measuring device · · • '. sign the second input connected to the generator output and compare the metric to the frequency hold. Fraud-. · 1 ·. the company is identified by the magnitude of the difference between the measurement value and the holding value • »·. ···.

• »

The third and second versions can be combined successfully \ 1: 35 in mixed fashion.

«» «•« «« «« · «« • · «• ·« • · «1 ·. 104922 6

In the fourth version of the apparatus, resonator 1 is either a parallel resonant circuit consisting of coil Lp and capacitor Cp according to Fig. 3 or serial resonant-5 siphon consisting of coil Ls and capacitor C according to Fig. 4, whose magnitude changes under input 13 (Fig. 1). The voltage or impedance in this version is preferably measured by the input E of the resonator 1 and compared to a predetermined holding value of the impedance or voltage that the resonator 1 has without the input line 13 in the contact portion 2.

Because the electrical properties of the resonant unit 6 in the Gigahertz region, which is galvanically connected to the contact portion 2 in the apparatus, is affected by the measurable input line 13, the input line 13 can be identified with certainty regardless of diameter, location or shielding.

The hardware can be located completely outside the card receiver since it is only connected to the contact portion 2. No precautions are required in the space between the electronic component of the chip card 3 (microchip 20 token or memory) and the card receiver insertion slot.

The resonator 1 is preferably coupled to each cos. fox portion 2 which contacts the potential blood 25 of the chip card 3 (Signal-Ground).

··· I In Fig. 5, the resonator 1 has a switching element 16 instead of a galvanic connector 1 (2) (Fig. 1) for non-galvanic connection of the resonator 1 to the terminals ··· ♦ 12 and thus to the input line 13. • · ·! 30 depending on the type of field element 16, capacitive or inductive.

.'2 · The coupling member 16 is formed to passively switch the resonator 1 into a * 1 ψ so that the voltage at the output of the resonator 1 is affected by the electric field 35 of the input line 13.

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Preferably, the coupling member 16 for capacitive coupling comprises a layer 17 of metal parallel to each of the largest flat surfaces of the chip card 3 disposed opposite the zone delimiting the connection points 12 5 of the chip card 3 and covering approximately the area of the zone.

The coupling member 16 is formed for inductively coupling the resonator 1 so that the current in the resonator 1 is affected by the magnetic field of the input line 13.

10 The electrical input line 13 coupled to the resonator 1 through the coupling member 16 at one of the connection points 12 changes the characteristics of the resonator 1 measured by the measuring apparatus 7.

In a further embodiment of the invention, the fraud attempt is detectable without the connection points 12 of the chip card 3 being galvanically connected to the contact members 2. The fraud attempt can thus be detected advantageously before inserting the contact members 2 into the access points 12 or also by inserting the chip card 3 largely independent of contacts 2 and wires 11.

Further, the properties of the resonator 1 are largely. independent of the 25 electronic components mounted on the chip card 3; the apparatus can thus be used for modifying. matte preferably for various applications of the chip card 3.

Figure 6 illustrates a portion of a fifth embodiment of the apparatus wherein the resonator 1 is an electrical conductor or a waveguide, wherein the resonator 1 has an output A and the resonator 1 is connected: 2]: connected to the switching member 16. The resonator 1 has another: 3: the outlet B which is connected to the other • · · of the measuring apparatus 7. The second outlet B is preferably located near the node of the standing wave. The measuring apparatus 7 can be used for 1 1 2 3 3

• · t M

8 104922 measure electrical voltage at output A - as explained above - and also at output B.

Fig. 7 shows a resonator 1 connected to the coupling member 16 having an input E and both outlets A and 5 B, a generator 4, an impedance converter 5, a measuring apparatus 7 and a control element 9. The measuring apparatus 7 preferably has a first inlet 19, an input member 20 connected to an output B, a first threshold switch 21 and a second threshold 10 switch 22, wherein both threshold switches 21 and 22 are connected from the output side to the control member 9.

The generator 4 preferably has a phase control circuit (PLL) 23, a voltage controlled oscillator (VCO) 24 connected to an output impedance converter 5 and a low-pass filter 25 coupled between the phase control circuit 23 and the impedance converter 5, the input E of the resonator 1 and the multi-pole control input 27 of the phase control circuit 23 is connected via bus 28 to the control means 20.

The phase control circuit 23 is implemented, for example, essentially with a component of type MC145191.

The reference input 29 of the first threshold switch 21 is: connected to the reference input 30 of the second threshold switch 22 and i «·. 25 connected via the balancing member 31 to the input E of the resonator 1.

• 1. The voltage changes at the input E of the resonator 1 caused by the ambient temperature fluctuations can be compensated by the balancing element 31 such that the reference signal at the output of the balancing element 31 or at both reference inputs 29 and 30 30 is largely temperature independent.

• M

The first threshold switch 21 has a signal input: ***: 32 connected to the output of the first input means 19.

• · ·

The signal input 33 of the second threshold switch 22 is connected to the output of the second input element 20.

104922 The resonator 1 formed as an electric conductor or a waveguide has a plurality of conductor portions connected by the switching members, whereupon at least one of the conductors is present, for example when reading the memory of the chip card 3 of the apparatus 5. and for writing, structure or function requires it - arranged to be portable.

In Fig. 8, reference numeral 34 denotes a first conductor portion and a second conductor portion 35 of a resonator 1 formed as a waveguide, having an input E at one end of the resonator 1 and connected to a switching member 16. The first conductor portion 34 adaptable to available space. The first conductor portion 34 has both outlets A and B and a first coupling portion 36.

One end of the second conductor portion 35 terminates in the coupling member 16 and the other end in the coupling portion 37.

The first conductor portion 34 is preferably a flexible cable 20 and the printed circuit has a coupling member 16 and a second conductor portion 35 with a coupling portion 37.

The first coupling portion 36 is located on a plane e2, a portion of which is limited by an imaginary border 38, which also surrounds the first coupling portion 36. The second coupling portion 37 is located on the second plane e2, • ♦. and a portion thereof is limited by a second imaginary border 39, which also surrounds the second coupling portion 37.

*. * * Both imaginary borders 38 and 39 surround contiguous areas.

• · ·

The second conductor section 35 is an arrow 40 in the direction of at least: *** so far moved that both the lead parts 34 and / or 35 may be coupled to the two coupling parts 36 and 37, optimally a single wave resonator 1. Each • · * «· • · · • The advantageous coupling of the 104922 conductor portion 34 and 35 is achieved when the two edges 38 and 39 in Figure 8 overlap.

Moving the second conductor portion 35 in the direction of arrow 40 to the apparatus for detecting fraud attempts to connect the chip 5 attached to the card 3, it can be disconnected from the chip card to move in the opposite direction of the arrow 40.

If necessary, a motion of the arrow 40 in the direction of insertion of the card 3 in the apparatus for reading and writing the memory chip 3.

10 In a preferred embodiment of the resonator 1, both input means 19 and 20 are disposed directly at the respective outlet A or B and implemented, for example, as a surface mounted device (SMD).

If necessary, both outlets A and B are located immediately adjacent to each other in the resonator 1 or physically implemented as a single outlet to which the measuring apparatus 7 can be connected.

A preferred embodiment of the coupling members 36 and 37 may each be achieved by one single thread 20 in the first conductor portion 34 and the second conductor portion 35.

The adjusting element 9 can be used to adjust at least two different values of the frequency of the generator 4, e.g. the first value is 500 MHz and the second value is 455 MHz.

The length of the second conductor portion 35 is preferably determined to be a quarter of the wavelength in the resonator 1 for the first value of the frequency, when the first conductor portion 34 is preferably a multiple of this half wavelength.

The method by which the fraud attempt can be detected by the apparatus of Figure 7 is described below.

• · ·

In the first step, the frequency · * », * of generator 4. is set to the first value. The first input element •> t * 19 senses the voltage at output A and compares it with the reference signal at the first threshold switch 21 · 21 in the reference input 29. If the detected voltage is not within the expected first range, detect fraud, interrupt the method, and discard the chip card 3.

If the first voltage detected at output A is within the expected range 5, the frequency of generator 4 is adjusted in the second step to a second value. The second input member 20 senses the voltage at the second output B and compares it at the second threshold switch 22 with the reference signal at the reference input 30. If the detected voltage is not within the expected range of 10, a fraud attempt is detected, the method is terminated, and the chip card 3 is discarded.

The chip card 3 is received only when the voltage perceived at the output frequency A at the first value of the frequency is in the first region and the voltage perceived at the output B at the second value of the oscillation is at the second area.

Because the resonator 1 is voltage sensed at at least two different values of frequency and compared to the holding value, fraudulent attempt can also be detected when the effective length of the input line 13 is a multiple of the half-wavelength of the oscillation in at least two values of the frequency.

In the apparatus of Fig. 7 without an input cable • <; 13 (Fig. 1) is preferably the first node of the first value y '25a of the frequency and the second node of the frequency ·. value at output B second node.

m \ 1 In a preferred method of determining an optimum frequency oscillation frequency · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · from the first extreme - for example the maximum - to ···. to the extreme value in the frequency range of the first node - for example, to the minimum. The frequency is further modified '·· /' 35 in the same direction and a second threshold frequency f2 is sensed when the 104922 output signal changes from the second extreme to the first extreme.

The optimal first value of the frequency is the average of each of the threshold frequencies f2 and f2; the first value is preferably 5 the geometric mean (fx f2) of each of the threshold frequencies f2 and f2.

An optimal second value of the frequency is determined when the method described is applied to the second node using the output signal at the second threshold switch 22.

The method for determining each optimum value of the oscillation frequency in the resonator 1 can advantageously be performed automatically. If necessary, each hardware application is fine-tuned according to the method.

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Claims (18)

13 104922 Claims: An apparatus for detecting fraud attempts by connecting an electrical input cable (13) to an access point (12) of a chip card (3) in a device for reading and writing the memory of a chip card (3), characterized in that the device has a resonance unit. (6) having a resonator (1) coupled to the connection point (12), the electrical characteristics of which are modified by the power supply line (13) and are detectable by the measuring apparatus (7). Apparatus according to claim 1, characterized in that the resonator (1) is galvanically connected to a contact portion (2) of the apparatus for reading and writing the chip card (3), which acts to contact the access point (12). Apparatus according to Claim 1, characterized in that the resonator (1) is capacitively or inductively coupled to the connection point (12) by means of a coupling element (16). Apparatus according to one of Claims 1 to 3, characterized in that the resonant unit (6) is constructed in such a way that at least in the absence of electrical power, «II * · 1 · 'in the resonator (1) can be generated. tighten the input cable (13). Device according to one of Claims 1 to 4, characterized in that the resonator (1) is · 1 · 1: an electric conductor. • · Apparatus according to claim 5, characterized in that the electric conductor has a first conductor part (34) having a first coupling part (36) and a second conductor part (35), having a second coupling field portion (37), wherein each conductor portion (34; 35) can be capacitively or inductively coupled by each coupling portion (36; 37). · • · · «« • · · • • • 14 104922 Apparatus according to claim 5 or 6, characterized in that the electrical conductor has at least one outlet (A) connected to a measuring device (7) by means of which the voltage at the outlet (A) can be measured. Device according to one of Claims 1 to 3, characterized in that the resonator (1) is a vibration circuit having a capacitor (Cs) and a coil (Ls) connected in series with the capacitor (Cs). Apparatus according to one of claims 1 to 3, characterized in that the resonator (1) is a vibration circuit having a capacitor (Cp) and a coil (Lp) connected in parallel with the capacitor (Cp). Apparatus according to claim 7, characterized in that the electric conductor has a second outlet (B) connected to a measuring device (7) by means of which the voltage at the second outlet (B) can be measured. Apparatus according to one of Claims 1 to 10, characterized in that the resonator (1) is capable of generating a vibration whose frequency can be adjusted, the first and at least the second value being selected as the frequency. Apparatus according to one of claims 1 to 11, characterized in that the resonator (1) is connected via an impedance converter (5) to a generator • t ·; 25 (4) having a voltage controlled oscillator (24) and a phase control circuit (23). ** * 13. Method for Detecting Fraudulent Attempts Using One of the Hardware of Claims 1-12, • · · t #:! characterized in that the impedance is measured at the input of the resonator (1) and compared to the impedance holding value of the resonator (1) without the input line (13) at the connection point (12). A method for detecting fraud attempts by means of one of the devices according to claims 1 to 12, characterized in that the resonator (1) generates a vibration and that the voltage is measured from the resonator (1) and compared to a holding value the resonator (1) is provided without an input line (13) at the connection point (12). Method for detecting fraud attempts by means of an apparatus according to one of claims 1 to 12, characterized in that a resonator (1) generates a vibration having a first value and that a voltage is measured from the resonator (1) and compared to a holding value which can be measured from the resonator (1). ) Without the input line (13) at the connection point (12), adjusting the frequency to a second value different from the first and comparing the voltage with a second setpoint which can be measured from the resonator (1) without the input line (13) at the connection point The si-15 smartcard (3) is received only when the voltage in the resonator at the first and second values of the frequency is within a predetermined range. Method for detecting fraud by means of apparatus 20 according to one of claims 7 or 10 to 12, characterized in that the voltage is measured at the outlet (A) and compared with the voltage holding value at the outlet (A) when the input line (13) is not connected. , to the connection point (12). «· < 17. Method for Detecting Fraudulent Attempts in One> «! The apparatus according to claim 7 or 10 to 12. characterized in that the impedance is measured * 'at the input of the resonator (l) and compared with the holding value of the impedance: .1 in the resonator (1) without the input line ι · ι ·. 1 (13) at the connection point (12); is measured at output 30 (A) and compared to the voltage holding value at output (A) when the input cable (13) is not connected to the • · · · '1 · connection point (12). »··. 18. A method for detecting fraud attempts by one The apparatus according to claim 7 or 10 to 12, characterized by the fact that the resonator (1) has 4 M · 104922 16 the frequency of the input signal is changed until the voltage at the output (A) reaches a certain target value, after which the frequency of the input signal is measured and compared to the frequency hold value, whereby the output voltage (A) 5 has a specific target value with holding value and the input line (13) is not connected to the connection point (12). • • • • • • • • • • • • · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 104922 17