FR2888691A1 - TRANSACTION AUTHORIZATION METHOD AND DEVICE - Google Patents

Abstract

The invention relates to a method for authorizing a transaction performed via a computer network and from a first terminal (A), said method comprising: reading a personal information (PAN) present on a card (C) from a reader (L) of cards of the first terminal (A). and entering a personal identification code (PIN1) on an interface (CL) of said first terminal (A), the personal identification code (PIN1) being authenticated by comparison with a reference code (PIN) which is linked to said personal information (PAN), to authorize the realization of the transaction, characterized in that:. the method comprises, prior to the entry of the personal identification code (PIN1), a step of generating said identification code, from:> a password generated with limited validity (OTP) and> said reference code (PINE),. said personal identification code (PIN1) being a code with a limited validity, different from the reference code (PIN). The invention also relates to a terminal for implementing such a method.

Description

2888691 1

  BACKGROUND OF THE INVENTION AND PRIOR ART The invention relates to a method for authorizing a transaction carried out via a computer network and from a terminal, said method comprising: the reading of personal information present on a card from a terminal card reader, É and the entry of a personal identification code on an interface of said terminal, the personal identification code being authenticated by comparison (direct or indirect) to a code of reference that is related to said personal information, to authorize the completion of the transaction.

  And the invention also relates to an associated device.

  An example of application of the invention which will be more particularly illustrated in this text relates to the terminals of the ATM type (English: Automatic Teller Machine "ATM"). However, the invention generally applies to any terminal allowing a user to perform a transaction using a card.

  Returning to the particular example of a transaction to be performed on an ATM, the use of the card is protected by a personal identification code, stored in a memory of the network and called PIN code (which we can simply designate by PIN in the rest of this text).

  The transaction is allowed on the terminal (the ATM in the particular example that will be developed) only if the user correctly performs an authentication step, by inserting his card in the ATM reader and entering the correct PIN code associated with the card on it.

  This authentication of the user also involves a personal information of the user (that we will name PAN information), which is also stored in the card (for example in its 2888691 2 chip, in a magnetic strip of the card or in any other means of storing information of the card that can be read by the reader of the terminal).

  PAN personal information is read by the ATM reader as well as the code entered by the user.

  The PIN information has been generated by means of the network (or other independent generation means) from the PAN code to which it is thus linked.

  More specifically, PIN has been generated from a given secret algorithm 10, one input of which is PAN. The knowledge of the algorithm, the associated secret and that of PAN makes it possible to reconstitute PIN.

  An authentication operation as mentioned above is illustrated in FIG.

  In this figure, a user approaches his card from the ATM reader (step 1). The reader then reads the personal information PAN of the card (step 2), for example a magnetic strip of the card, or its chip, or any other means of logging information of the card.

  The user then enters (step 3) his PIN code in the reader, through an interface such as a keyboard. Any other type of interface is also possible (sound interface, biometric, etc.).

  Both PAN and PIN information are then encrypted and transmitted in encrypted form <PAN> and <PIN> by the ATM to the network (step 4).

  A server connected to the network (ATM server in the figure) receives these two encrypted information and decrypts and validates the PAN personal information (step 5).

  By validation of PAN is meant verification of the PAN format as personal information, compared to an expected format. This validation may also involve a comparison with a list of personal information stored in the ATM server.

  This ATM server has a memory in which the characteristics of the algorithm for calculating PIN from PAN 2888691 3 are stored. These characteristics are represented on the figure by a PIN offset DBs.

  The ATM server transmits, in a next step 6, the decrypted PAN, the PIN offset DBs and the encrypted information <PIN> to a machine PIN which is connected to it, and which is capable of performing the following operations (step 7): É Decryption of <PIN> to PIN, É Calculation of PIN information 'from PAN and PIN offset DBs, using a PIN generation algorithm'. This algorithm is identical to the algorithm that made it possible to calculate PIN from PAN, or is related to it, É Comparison of PIN information with PIN.

  Authentication is performed if a predetermined law is satisfied between these two pieces of information.

  This law can be for example simply the equality: PIN '= PIN (in this case the algorithm of development of PIN' is identical to the algorithm which made it possible to elaborate PIN starting from PAN).

  It is specified that encryption and decryption of data are not mandatory. In a simplified version PAN and PIN are transmitted in their original unencrypted form (this also being applicable to the invention).

  Summary of the Invention An authentication procedure as described above has a significant degree of security.

  However, it is exposed to the risk of fraud at the terminal.

  Indeed, a fraud may consist in stealing at the terminal 30 the personal information PAN and the PIN entered by the user.

  This can be envisaged for example by adding on the terminal a false card reader, to read PAN personal information when the card is inserted therein, and a hidden camera to film the keyboard that the user uses to compose his code. identification PIN.

  The fraudster having thus read the information PAN and PIN can use this information to perform transactions in the place 5 of the user and without his knowledge, or to make a false card with personal information PAN and introduce it into a ATM reader using the PIN code also stolen.

  An object of the invention is to obtain a method and a device for preventing such a risk of fraud.

  Another objective of the invention is also to prevent the risk of fraud, without requiring a very significant modification of the infrastructure (and in particular terminals scattered over a territory) to implement an authentication procedure of the type of outlined above.

  For this purpose, the invention proposes a method of authorization of a transaction carried out via a computer network and from a first terminal, said method comprising: E reading a personal information present on a card from a card reader of the first terminal E and the entry of a personal identification code on an interface of said first terminal, the personal identification code being authenticated by comparison with a reference code which is linked to said personal information , to authorize the realization of the transaction, characterized in that: the method comprises prior to the entry of the personal identification code a step of generating said identification code, from: a password generated to limited validity and said reference code, e said personal identification code being a limited validity code, different from the reference code.

  Preferred but nonlimiting aspects of the method according to the invention are the following: the user acquires knowledge of the personal identification code on a second terminal; the identification code generation step is carried out by means of said second terminal, - for the step of generating personal identification code, the following operations are performed on said second terminal: É Activation on the second terminal of a computer application 10 for generating a password for use limited, É Transmission of said limited-use password by the second terminal to a server, for validation of the limited-use password, É Validation of said limited-use password, É Generation by the second terminal of said identification code staff.

  the step of generating a limited-use password is performed by a server connected to said second terminal, and capable of transmitting said limited-use password to said second terminal which generates said personal identification code; for generating a limited-use password is triggered by means of the second terminal, - the step of generating a limited-use password is triggered by means of the first terminal, - the transmission step between the connected server. at the second terminal and said second terminal is via a telecommunications network - the telecommunications network is a GSM, CDMA, UMTS, GPRS, 3G or WiMAX network, - the personal identification code has been generated with an algorithm whose entry is personal information, - the process consists of the following steps: 2888691 6 É Transmission of personal information and personal identification code by the first terminal to a server connected to the network, É Receipt of these two data by a server connected to the network and validation of the personal information, É Transmission by said server connected to the network to processing means: Characteristics said algorithm, of said personal information, of the personal identification code, É Realization by said processing means of the following operations: Calculation of an information from the personal information and said characteristics of the algorithm, comparison of the information thus calculated with said reference code, to verify that a predetermined relationship is verified, the method comprises the following steps: É Encryption of the personal information and the personal identification code 20, É Transmission of these two data under encrypted form, by the first terminal to a server connected to the network, É Receipt of these two data encrypted by u n server connected to the network and decryption of the encrypted personal information and validation of the personal information, É Transmission by said server connected to the network to processing means: É Characteristics of said algorithm, É said personal information, - Du encrypted personal identification code, É Realization by said processing means of the following operations:> Decryption of said encrypted personal identification code, É Calculation of information from the personal information and said characteristics of the algorithm, Comparison of the information thus calculated with said reference code, to verify that a predetermined relationship is verified, the limited validity of said personal identification code corresponds to a temporary validity during a given period, the limited validity of said personal identification code corresponds to a limited validity for a number of transactions given only, - the limited validity of said personal identification code corresponds to a validity limited to a single transaction. The invention also relates to a terminal for the implementation of a method as described previously used as a second terminal. characterized in that said second terminal includes means for initiating the generation of said personal identification code from said reference code.

  Preferred but nonlimiting aspects of the terminal are that it comprises means for generating said personal identification code from said reference code.

  The invention will be better understood on reading the description which will follow, given solely by way of nonlimiting example, with reference to the appended drawings, in which in addition to FIG. 1 which has already been commented on above, FIG. a diagram of an embodiment of the method and the device for establishing a transaction according to the invention.

  This figure illustrates the particular example of implementation of the invention which concerns the authorization of a transaction on a banking network, with a terminal in the form of an ATM terminal.

  DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION FIG. 2 represents the elements of the device making it possible to implement the invention, and the information flows between them.

  This figure includes the elements (means, operations and flow) of the diagram of Figure 1 these elements will not be introduced a second time. It is furthermore specified that all the indications which have been given with regard to FIG. 1 (in particular indications that means such as reader interfaces, etc. may be of different natures) are also applicable to the invention.

  Figure 2 further comprises elements which are new compared to the representation of Figure 1: E second terminal (represented here by a mobile phone), É and two servers in the lower part of the figure.

  The role of these elements will be specified below.

  It is specified that the ATM server and the machine PIN can constitute one and the same entity, and be confused.

  In Figure 2, an ATM terminal includes a card reader and an interface, such as for example a keyboard, by which a user can enter a personal identification code.

  As has already been pointed out above, the terminal may be of any type different from an ATM terminal (it may for example be a computer or a peripheral of a computer, a remote payment terminal of the terminal type EFTPOS for Electronic Financial Transaction Point Of Sale, etc.), and similarly the interface may be of a different type than a keyboard.

  The terminal will be used by a user to establish a transaction (for example financial), using a card. And at first, it will be used to authorize this transaction.

  As will be seen, the invention implements a second terminal, which is schematized here by a mobile phone. The ATM terminal corresponds here to a first terminal, and it will be designated as such in this text (we use indifferently the terms first terminal, terminal ATM, or even ATM anyway to designate it).

  This first terminal is connected to a network (a banking network in the case of Figure 2).

  The cards that can be read by the ATM terminal reader can be of any type, such as for example magnetic stripe cards only, smart cards, cards with a magnetic stripe and a chip, or any another means of recording a PAN personal information of the user, such as for example a bank account number code.

  In any case, this personal information will be read by the ATM reader.

  The authorization process for establishing a transaction according to the invention also requires, as the known method commented on with reference to FIG. 1, that the user enters a personal identification code in the ATM terminal.

  In the case of the invention, this code (which is referred to as PIN1 in FIG. 2) is of limited validity and has previously been obtained by the user in order to be able to enter it into the ATM terminal.

  The limited validity of this PIN1 code may correspond to a temporary validity during a given period, or a limited validity for a given number of transactions only (a transaction counter incrementing in this case with each new transaction), or a validity limited to a single transaction. In the example that will be described below, it is a validity limited to a single transaction.

  A method for obtaining this PIN1 code will now be described briefly, this obtaining representing a first phase of the method according to the invention.

  To obtain the PIN1 code the user uses the second terminal, which is here represented as a mobile phone. This second terminal can be of any other type.

  Whatever its format, this second terminal can enter into communication (transmission and reception) with a server G connected to the machine PIN. This connection can be direct, or an additional server (referenced here SV) can be interposed between the machine PIN and the server G which communicates with the second terminal, as shown in Figures 2 and 3.

  In the embodiment of these figures, the communication between the second terminal and the server G is via a wireless telecommunications network, such as a GSM network, CDMA, UMTS, GPRS, 3G, WiMAX for example.

  The steps enabling the user to obtain a PIN1 for use are the following: Step A: The user activates on the second terminal a computer application for generating a limited-use password referenced here OTP (For One Time Password according to the English terminology widespread single-use password it is recalled in fact that in the particular and non-limiting example explained with reference to Figure 2, the PIN1 code is a single-use code), Step B: The OTP password is transmitted by the second terminal to the server G (here by a GSM type network), for validation of this OTP.

  Step C: the limited password is validated, that is to say that its format and its value are recognized as corresponding to a valid limited password. This recognition is done by comparison with stored format information and values (here in the server SV and the validation is done after a dialogue between the server G and the server SV), E step D: once the validated OTP password has been validated, a validation message is returned by the server G to the second terminal, to indicate that the OTP-validated password has been validated, E step E: after receipt of the validation message , the application of the second terminal generates a PIN1 code, combining according to a 2888691 11 given algorithm information PIN and OTP. This algorithm (represented by XOR in the figures) is also stored in the machine PIN, which will retrieve the PIN information, and the PIN1 code thus produced is provided by the second terminal to the user (for example by a message on the terminal screen).

  Alternatively, it is possible that the second terminal does not generate itself the OTP limited password.

  Indeed, if this second terminal is still able to receive the OTP limited password to generate a PIN1 code, it is possible that this OTP limited password 10 is generated by a server connected to the computer network, in particular by the server G In this case the OTP limited password is transmitted by the server to the second terminal.

  And still in this case, the generation of the OTP limited password in the server can be triggered: by the second terminal, a computer application sends to the server a signal (such as an SMS) triggering the generation of a limited password, or É by the first terminal, in a variant of the invention wherein the first terminal includes an application and / or means to allow the user to trigger the generation of a limited password. In this case, a certain adaptation of the first terminal is necessary, and this first terminal is connected to the server which will generate the limited password and transmit it to the second terminal.

  Once the user has the PIN1 code, he uses this PIN1 in the same way as the PIN mentioned with reference to FIG. 1, that is to say, as an identification code provided to the ATM terminal reader. and to allow a transaction.

  The rest of the process generally proceeds as already mentioned with reference to FIG. 1, with a PIN1 instead of the PIN code.

  However, a modification of this part of the authentication procedure is necessary in the case of the invention, because the algorithm stored in the machine PIN for reconstituting a PIN 'value from PAN does not make it possible to directly reconstruct a information comparable to PIN1.

  We will now expose the elements that allow to authorize a transaction, once the information PAN, PIN offset and <PIN1> have been transmitted to the machine PIN by the ATM server.

  When this information is received by the machine PIN, it sends the server SV a request to obtain the OTP limited password, and receives this limited password. This transmission of OTP may also have been done automatically by the server SV, for example as soon as this limited password has been validated.

  An additional difference with respect to the method of the prior art illustrated in FIG. 1 is that, in the case of the invention, at the end of the method the machine PIN calculates the value of the reference code PIN, from: E of the code identification PIN1 (which has been received from the ATM terminal and decrypted by the machine PIN), E and OTP (which has been received from the SV server).

  The end of the authorization procedure proceeds as in the case of Figure 1.

  The information that the OTP limited password has been used is transmitted by the machine PIN to the SV server.

  And this server SV takes into account this usage information to update the format and value information that it stores for the OTPs that will be transmitted to it by the second terminal as part of subsequent transaction requests.

  This update corresponds in particular to a prohibition of a later use of OTP, if this one is for single use or arrived at the end of permitted use. In the case where the OTP can be used a limited number of times, the update typically corresponds to the increment of a usage counter.

  By use of OTP is meant for example implementation of OTP to calculate PIN from PIN1, in the machine PIN. Alternatively, it is also possible to consider that the OTP was used as soon as it was transmitted by the server SV to the machine PIN.

  It should be noted that the invention makes it possible to substantially increase the security level of the transaction authorization.

  In particular, with the invention if a fraudster obtained the information PAN and PIN1 entered in the first terminal, it would not be possible for him to use this information to carry out fraudulent transactions, in any case not without limitation, even in a version the simplest of the invention in which the limited password can be used several times.

  And in the case where the OTP is for single use, the fraudster will not be able to use the information he has stolen to try to obtain authorization to carry out a transaction.

  It will also be noted that this increase in the security level is obtained by using conventional infrastructure and means (the diagram of FIG. 2 generally takes the elements of FIG. 1).

  In particular, the invention can be implemented with conventional cards and terminals (first terminals), such as those implemented in an authentication procedure as described with reference to FIG.

  In absolute terms, however, it can be imagined that the first and second terminals are combined into a single terminal.

  The only modification to be made to a conventional configuration as shown in Figure 1 is to provide servers G and SV, and slightly change the operation of the machine PIN.

  This is particularly advantageous, compared to alternative solutions that one could imagine to increase the security of transaction 2888691 but that would require modifications of all the first terminals for example.

2888691 15

Claims (17)

  1. A method for authorizing a transaction performed via a computer network and from a first terminal (A), said method comprising: E reading a personal information (PAN) present on a card (C) to from a reader (L) of cards of the first terminal (A) É and the entry of a personal identification code (PIN1) on an interface (CL) of said first terminal (A), the identification code personal (PIN1) being authenticated by comparison with a reference code (PIN) which is linked to said personal information (PAN), to authorize the realization of the transaction, characterized in that: É the method comprises prior to entry of the personal identification code (PIN1) a step of generating said identification code, from:> a password generated with limited validity (OTP) and said reference code (PIN), É said code of identification (PIN1) being a code with a limited validity, different from reference code (PIN).   2. Method according to the preceding claim, characterized in that the user acquires the personal identification code (PIN1) on a second terminal.   3. Method according to the preceding claim, characterized in that said step of generating identification code (PIN1) is performed by means of said second terminal.   4. Method according to the preceding claim, characterized in that for said step of generating personal identification code 2888691 16 (PIN1) the following operations are performed on said second terminal: É Activation on the second terminal of a computer application allowing to generate a limited-use password (OTP), É Transmission of said limited-use password (OTP) by the second terminal to a server (G), for validation of the limited-use password, É Validation of said word limited-use password, E Generation by the second terminal of said personal identification code (PIN1).   5. Method according to claim 2, characterized in that said step of generating a password for limited use (OTP) is performed by a server (G) connected to said second terminal, and able to transmit said password to use limited (OTP) to said second terminal which generates said personal identification code (PIN1).   The method of claim 4 or claim 5, characterized in that the generation of the limited use password (OTP) is initiated by means of the second terminal.   7. Method according to claim 4 or claim 5, characterized in that the generation of limited-use password (OTP) is triggered by means of the first terminal.   8. Method according to one of the four preceding claims, characterized in that the transmission between the server connected to the second terminal and said second terminal is via a telecommunications network.   2888691 17 9. Method according to the preceding claim, characterized in that said telecommunications network is a GSM network, CDMA, UMTS, GPRS, 3G or WiMAX.   10. Method according to one of the preceding claims, characterized in that said personal identification code (PIN1) has been generated with an algorithm whose input is the personal information (PAN).   11. Method according to one of the preceding claims, characterized in that said method comprises the following steps: É Transmission of personal information (PAN) and personal identification code (PIN1), by the first terminal (A) to a server (ATM server) connected to the network, É Reception of these two data by a server connected to the network 15 (ATM server) and validation of personal information (PAN), É Transmission by said server connected to the network (ATM server ) to processing means (PIN machine): characteristics of said algorithm (PIN offset), said personal information (PAN), personal identification code (PIN1), É realization by said processing means (PIN machine) of following operations: Computation of information (PIN ') from personal information (PAN) and said characteristics of the algorithm (PIN offset), comparison of information thus calculated (PIN') with said code of referen this (PIN), to verify that a predetermined relation is well verified.   12. Method according to the preceding claim, characterized in that said method comprises the following steps: 2888691 18 Encryption of personal information (PAN) and personal identification code (PIN1), É Transmission of these two data in form encrypted (<PAN>, <PIN1>), by the first terminal (A) to a server (ATM server) 5 connected to the network, É Receipt of these two encrypted data by a server connected to the network (ATM server) and decryption of personal information encrypted (<PAN>) and validation of personal information (PAN), É Transmission by said server connected to the network (ATM server) to 10 processing means (PIN machine): Characteristics of said algorithm (PIN offset), of said personal information (PAN), of the encrypted personal identification code (<PIN1>), É Realization by said processing means (PIN machine) of the following 15 operations: Decryption of said encrypted personal identification code (< P IN1>), calculation of information (PIN ') from personal information (PAN) and said characteristics of the algorithm (PIN offset), comparison of information thus calculated (PIN') with said code reference (PIN), to verify that a predetermined relationship is verified.   13. Method according to one of the preceding claims, characterized in that the limited validity of said personal identification code (PIN1) corresponds to a temporary validity for a given period.   14. Method according to one of claims 1 to 12, characterized in that the limited validity of said personal identification code (PIN1) corresponds to a limited validity for a given number of transactions only.   2888691 19 15. Method according to one of claims 1 to 12, characterized in that the limited validity of said personal identification code (PIN1) corresponds to a validity limited to a single transaction.   16. Terminal for implementing a method according to one of the preceding claims taken in combination with claim 2 as a second terminal, characterized in that said second terminal comprises means for triggering the generation of said identification code. personnel (PIN1) from said reference code (PIN).   17. Terminal according to the preceding claim characterized in that it comprises means for generating said personal identification code (PIN1) from said reference code (PIN).