FR2790854A1 - Device for securing computer data exchanges of payment or remote payment has inaccessible area in secret memory in which primary codes of list may be used as preference for secure exchange - Google Patents

Abstract

Codes may be stored an inaccessible area in a secret memory and e.g. a primary code(s) of the list that may be uses as preference for secure an exchange. After that separated codes are returned as inaccessible and other code(s) remaining on the list may be used for the same or another exchange procedures.

Description

- 1 - The present invention is in the field of recognition

  stakeholders and securing the exchange of computer data mainly between computers that transmit clear, encoded or encrypted digital data, in particular for electronic payment or

telepayment.

  Whatever the level of complexity or sophistication of a remote payment or on-site payment security system using a certification involving the exchange of data, even encrypted, or creating or recognizing a digital signature, communication and data transfer can always be hacked to be used unlawfully with increasingly sophisticated equipment and increasingly ingenious hackers when it comes to data, codes or digital signatures that can be reused. Hacking can attack computers themselves, for example with the intrusion of "Trojan horse" viruses, which make it possible, among other things, to recognize and store a secret code when it is used in the computer to then delicately send a copy to another computer; this hacking can also attack communications between computers (or peripherals such as smart card readers) whatever the channels used (electric telephone lines, optical fibers, links

satellites or others).

  The criminal re-use of pirated data without the knowledge of the legitimate users of this data is the weak point of securing exchanges of digital data and particularly of any means of electronic payment or

telepayment.

  In order to remedy these drawbacks and according to a first characteristic, the device according to the invention comprises a support which uses data for the purpose of securing which can only be used a limited number of times and preferably only once. These data are preferably stored in the form of a large number of codes on said medium used for the exchange (for example a payment), preferably arranged in a single list and which can only be used a limited number of times. and preferably only once. Preferably in the recipient's computer system, a second storage of data identical to that stored on said medium and in the same order makes it possible to identify each code proposed as coming from said medium. Each time a code is exchanged between two IT devices, it is counted to serve only a predetermined number of times, this number of times being reached, it is rendered unusable, this is the code (s) ( s) following in the list of codes which will be usable for the following exchange. For greater security, the number of times that the same code can be used is preferably reduced to only once. Thus such data intercepted in a criminal manner will be difficult to re-use and even

  unusable, by a hacker, if this data can only be used once.

  On the other hand, several versions producing different embodiments

will be described later.

  Throughout the present description and in the claims, the terms

  The following are used according to the definition indicated for understanding but not restrictive: - authority: individual or organization which issues and / or manages the use of media with a view to accepting or refusing authentication and / or payment and / or wire payment; in certain cases, the authority may also be directly concerned by the exchange of data in the form, for example, of a message, as a sender or as a receiver while ensuring the security of the exchange; in the case of an exchange between individuals, between companies, from individual to company or between other entities, one of the participants can be the authority or even the two participants, allowing mutual authentication, - bank: in some cases it is authority; it can delegate all or part of its powers to a third party which becomes the authority in the system of securing exchanges, - trader: supplier of products and / or services, code: it can be at least one word, in the computer sense, and / or at least one algorithm and / or an assembly of digital data in any form whatsoever, making it possible to identify or be identified, during an exchange, by its appearance, its shape which can be compared to an assembly of

digital witness data.

  - exchange: sending digital data from a transmitter to a receiver; the communication of data can be done in both directions during the same exchange and allows the sending of messages, codes, ... in order to carry out a complete operation like a payment with verifications on the speakers; The exchange can be carried out on the spot by the carrier for example by a payment by chip card, or remotely for example by the intermediary of a computer connected to another computer by a telephone line, - digital : is used in the sense of the system which is used by computers, in principle the binary system, and which can be represented by other systems (octal, hexadecimal, ...) or supplemented or replaced by a system with intermediate values resulting from fuzzy logic, - pirate: an individual or a group who commits criminal acts in an attempt to divert, to appropriate confidential information for themselves or to replace a merchant, a carrier or a authority to divert funds for its benefit; it can act at all levels of an exchange: theft of a medium, intrusion into computer exchanges to produce false media or false computer data ..., - carrier: it is the authentic owner of a medium with which he can carry out exchanges with a merchant, with his bank or with another entity, locally or remotely, - medium: device where you can store computer data in memory and also including functions allowing, among other things , to carry out exchanges; the support can be a card, preferably of the bank card type, or a disk (diskette, CD ROM or other) with magnetic and / or optical reading or any object (ring, watch, spectacle frame, key ring, pendant , ...) can integrate a computer system necessary for a secure exchange via a computer device such as a computer with or without the help of a reader. The support can also be autonomous, with the possible exception of an energy source, and do without the intermediary of a computer to carry out exchanges with computer hardware. Exchanges can be made with or without electrical contact between the support and

  any other electronic or computer equipment.

  According to particular embodiments: - the codes can be extracted from at least one list of codes: 1) one by one and there is access, after each extraction, only to the first code, the only provisionally available, 2 ) one by one or by groups, each code extracted immediately following the code previously extracted from at least one list, 3) randomly and coupled with additional data so that they can be compared with the same codes from a control list, 4) according to a pre-established plan or established during the exchange and coupled with additional data in order to be able to compare them with the same codes -4- from a witness list, - the list (s) of codes can (can ) be supplemented or replaced by at least one algorithm capable of creating codes as and when necessary resulting from the use of the medium; at least one algorithm installed in the authority's computer system creates the same codes to compare them with those of the medium when an exchange with this medium requires a

authentication of said medium.

  - the data concerning an exchange, any clear operation, coded or encrypted can be associated with at least one code from the list

  registered on the support or created by the latter's system.

  - the support can only be used through a small number of computers

  individuals (preferably only one computer) to carry out exchanges.

  - the use of the support may be subject to a variable code specific to the

holder of the support.

  - a trapped code can prohibit the use of the support in the event of an attempt

to use this code.

  - a detection device using for example at least one clock signal or any other signal having the same function can be associated with the system to ensure that each exchange is transmitted in full, in real time and without

interruption.

  - The characteristics of at least one clock signal or of any other signal having the same function can have expected, preferably secret, variations. - the medium can only function, when requested for an exchange, if the authority sends it at least one code, which preferably changes with each exchange or attempted exchange that said medium recognizes, authenticating the authority, after which only it produces identification data which the authority will have to recognize with a view to mutual authentication, - the identification of the bearer can be done by several means including a device

  secondary essential for the functioning of the support.

  In a first embodiment which is in no way limitative, the device which is the subject of the invention is in the form of a medium which can, in particular, store a large quantity of digital data preferably in the form of codes which are arranged in at least one list made inaccessible to consultation and / or modification once it is written to at least one secret memory of the medium, except for the first code (s) in this list which may be ) be consulted, used for example for authentication in an exchange. By design of the support, each code can only be used a limited number of times and preferably only once after which it can be discarded, erased or made inaccessible and it is the following code (s) ( s) of said list which is (are) usable (s) and each time under certain conditions

described later.

  Different embodiments, for performing an authentication of a support or of an entity, are defined below on the basis of the use of at least a secret memory and of codes which can preferably be used a limited number of times or only once during an exchange: 1) at least one code is used for an exchange, the first of said list then the next code in said list and so on, 2) several codes are used for an exchange, extracts a by one or by groups and always each extracted code succeeds in said list to the previously extracted code, 3) it is at least one secret zone associated with at least one secret memory of the support system which determines the random search for one or more code (s) in said list (s) and which addresses the code (s) chosen to at least one other intervening entity as well as the additional indications making it possible to compare this / these code (s) with that (those) whose indications c correspond in the own list of the other entity or entities; the secret zone is preferably not modifiable nor accessible for consultation and / or external manipulation (s), it cannot be extracted therefrom data other than that which it is planned to extract, cannot transform the operation of the secret memory nor extract therefrom data other than that which it is intended that this secret memory can supply or extract data other than it is expected that said memory provides them; said additional indications accompanying the code (s) are for example the position (s) in the list (s), the number (s) or the coordinates or the marker (s) of this (s) code (s), 4) the device is identical to that of 3 above except for the search for a code (s) which is not done randomly but following a plan individual pre-established or established during the exchange, the course of which is contained or can be established, created, in at least one secret zone of the support and in the computer system of the authority and / or at least -6-

another entity.

  Preferably only in the last two embodiments above

  above (3 and 4) the codes are arranged randomly or arranged or ordered according to certain criteria, the additional indications making it possible to find and compare each code with at least one code from at least one other witness list are exchanged thanks to a single exchange, the one also containing the classic data of an exchange such as a message, or in a different exchange (s) or fragmented and divided into several exchanges in order to make their consultation even more complex even if their reuse is not envisaged and if a hacker intercepting them cannot reuse them. To protect very confidential data, said additional information will be sent to its recipient by different channels

  of those who transmit the content of a message.

  In said first embodiment, said codes contained in at least one list follow one another in an unpredictable manner, for an observer external to the establishment of the list and to its confidentiality, are designed for example randomly using software whose has the authority which realizes and which has the codes in two identical lists, one is registered on a support which will be provided to an authorized carrier, known to the authority, the other remains in memory in the computer system of the authority to allow the comparison of at least one code to the corresponding code in the other list. Such a random arrangement of a large number of codes makes it possible to produce with the same software a large number of lists different from each other attributable to a large

number of carriers.

  Said medium makes it possible to exchange computer data used by the authority to authenticate the medium, and then to exchange data which may be confidential, which engage the parties which may, for example, be specific to a company which corresponds with its branches or any other type. exchange of data that we want to keep confidential, which allows in particular to secure a payment on the spot, at the place of the transaction thanks to the medium used for this purpose or to secure a remote payment made by

  example thanks to a computer connected to a computer network.

  In the case where the data is confidential, a coding or an encryption is preferably used with a more or less high degree of confidentiality while respecting the regulations of the State (s) o these

data must flow.

  -7- Preferably and contrary to the operating mode of the support, the authority's computer system can consult the previous codes and the following codes in its own memory during an exchange in order to avoid blocking of this type of exchange if, following improper handling of the carrier or improper transmission of data, a code must be eliminated to make room for the next one when the authority has not yet registered that

  last code was issued by support.

  To avoid replacing the medium issued or validated by the authority with a false medium apparently having the content of an authentic medium, trying to find the right code by making a large number and offering them one by one to the authority, after a certain number of attempts which do not provide the correct code, predetermined number in agreement with the authentic bearer, the authority's computer system can block the use of this medium, for example inform the merchant with which a payment is in progress or keep the support if the attempt is made with an ATM for example. After a blocking of this type, the support may be permanently unusable or the bearer must provide proof of his identity by going physically to the authority to find that he is the authorized bearer and unblock the use of this support in the authority's computer system. This constraint is in reality a security measure against the use of a false medium in the name of an authorized carrier and without his knowledge. For the authorized wearer this type of blocking should never be applied in a usage

normal support.

  By this characteristic of identical lists on the medium and in the authority's computer system, the latter eliminates the risks: of use and payment with a false medium, - of a criminal wire payment by having hacked the digital data exchanged , during a previous payment or electronic payment, between a medium

and an authority.

  Whatever the degree of technology used for such hacking, the code used for a payment or electronic payment with a secure medium as described above is used and therefore consultable, preferably, only for a single exchange and not being no longer valid for another exchange, the hacked data cannot be used. If the code can be used several times for securing

is less effective.

  However, advanced pirating, during a payment, could consist in diverting the communication channel between the merchant and the bank. Upon contacting the merchant with the bearer's bank, the communication would in fact reach a false bank which could interrogate the medium presented, extract the first code from it, send the merchant false payment acceptance data for do not give wake-up even if this payment does not take place and immediately use the code provided by the support for another transaction to the detriment of the holder or the trader or the

  bank according to the prior agreements between the participants.

  Although this type of action requires high technicality, it is good to protect it for example by providing the merchant with a system similar to that described above comprising at least a couple of two identical lists of codes which cannot be can consult preferably only one code or a limited number of codes at the same time but in this use of the lists of codes it is the merchant who is the authority in order to recognize, to authenticate the bank of the bearer. Banks wishing to participate in this security can also authenticate each other, during their exchanges by also using lists

of codes as described above.

  All participants are thus mutually authenticated, which avoids an exchange with a false participant. Only the holder does not seem to have reliable indications of authentication either from the merchant or the bank, he relies on the indications provided by the merchant or by a cashier monitor but in fact the payment cannot be made only if the bank has authenticated its support which is equivalent for the holder to have authenticated its

bank if his account is debited.

  To increase the security of the support object of the invention, the system can allow the use of several codes during the same operation. These codes come from at least one list, one by one and in the order in which they are written on the support as described above. If it seems unlikely to discover by chance which is the correct code at a given moment in the course of the use of the medium, it seems impossible to discover, also by chance,

  several successive codes in the order in which they are entered.

  For the sake of simple use of the system, it is preferable that each authentication operation is carried out automatically by each terminal of

each participant.

  The device according to the invention consists of a support having the particular characteristics described either above or in the various variants and / or of an operating system in which at least one support as described intervenes, the computer system of authority in combination, when necessary, with media readers and / or means of transmission and processing

  computer necessary for an exchange.

  Several variants are described below in which the support has in all cases the basic characteristic which is the presence of at least one

  list of codes contained in at least one secret memory.

  According to a first variant, at least one list of codes is completed or replaced by at least one algorithm capable of creating usable codes as and when the need arises from the use of the medium. At least one algorithm installed in the authority's computer system creates the same codes to compare them with those of the medium when an exchange with this medium requires, for example, authentication of said medium. Preferably said algorithm (s) is (are) not searchable or transformable to

  from the moment it (s) is (are) written in the support.

  According to another variant, the data other than the codes, relating to an exchange, a clear, coded or encrypted operation can be associated by the medium or by the computer system with which it communicates, transmitter or receiver, with at least one code of '' at least one list of codes written on the medium which makes the data difficult to falsify and which makes it possible to code an exchange in clear. The authority being the only one to know the code or codes used to decode this exchange, it being understood that these codes too are preferably different for each exchange. For an operation consisting of a payment, it is the assurance for the holder as for the merchant that the data as the conditions of an order, the reference of a product, the

  Payment amount cannot be changed during the exchange.

  According to another variant, the support can only be used for data exchanges and / or secure electronic payments from a reduced number of computers or media readers or peripheral devices for connection to at least one network, and preferably only one. of these devices, for example his personal computer or a specific computer of a company, to exchange, with another computer device. Reading and using said medium requires an exchange of data between said medium and the computer or reader or peripheral to which it is linked, inducing mutual recognition - of the two elements without which the medium does not provide the data it have and which are necessary for an exchange with another device

  IT in order to carry out a particular operation, in particular a payment.

  The support is preferably a disc which can be read by a reader forming an integral part of the computer or by a specific reader connected to this computer, which makes it possible to give the support the most diverse shape and appearance in addition to those of a disc. This limits the risk of theft of the support which can be used and stored in the same place which may only be accessible to the user. The support which is recognized only by a single computer hardware with which it is associated cannot be used from another hardware even of an identical type. According to another variant, the possibility of using the support is subject to the entry of a personal code specific to each carrier, secret, offered to the support system by a reader integrated in the support or by a conventional reader or by a computer without an external reader, for each use, in order to be recognized by the support which authorizes the wearer to continue his procedure with a view to a complete exchange. Said personal code varies over time in whole or in part according to modes that the wearer is the only one to know and that the medium recognizes. The variations are chosen by the wearer before the creation of the medium because they are easily memorized by the wearer as a function, for example, of his date of birth, even or odd days or hours, letters of a known name of the wearer ... Despite these variations, at some point,

  only one personal code is valid and accepted by the support.

  According to another variant, at least one trapped code can block the use of the support. Some holders write their personal code near their support, in the case of a bank card for example, to easily find it in case of forgetting. Unfortunately in case of theft of the support, it is likely that the thief will in this case be able to find the personal code to misuse the support. Said trapped code is preferably to be written on or near the support, for example in the portfolio which contains it. If a stolen medium is used before the authorized bearer has completed the formalities to block the use of this medium, if the thief uses this code, like a personal code, said code is transmitted to the authority which immediately prohibits any operation in progress and to come carried out with this support and warns the merchant,

- 11 -

  if it is a payment transaction with a merchant that this medium is certainly stolen; if it is an attempt to use in an automatic machine such as an ATM, the operation is refused and the support can be retained although it is no longer usable. If it is an error due to manipulation of the authentic wearer, the latter must physically approach the authority to prove his identity so that the use

  of its support is released in the computer system of said authority.

  According to another variant, a detection device is associated with the system to ensure that each exchange is transmitted in full, in real time and without interruption to prevent an exchange from being either partially diverted, or intercepted, modified and redirected more. late, either intercepted, modified and redirected in real time or almost what is more difficult to achieve. Said detection device, for example, emits at least one signal which can be a clock signal or any other signal having the same function associated with all or part of the data of an exchange so that these data are linked together, identifiable and inseparable except by leaving a trace. The authority's computer system detects any anomaly and can react, for example by asking for confirmation or by refusing authentication and the content of the exchange or by

  refusing payment if it is a payment procedure.

  According to a variant complementary to the previous variant, the characteristics of the clock signal (signals) or of any other signal having the same function, vary (s) in the same exchange and / or are different for each exchange. The mode of these variations is stored in a memory of the medium as well as in the memory of the computer system of the authority which controls the conformity of the variations. For an observer outside the confidentiality of said variations it is impossible to predict them which makes it impossible for said signal to be produced in real time by a hacker who would try to

  replace data with false data.

  Always for the sake of security, the mode of said variations is preferably inaccessible to consultation on the support even for the authority, it takes place at

  as and when the support is used according to a pre-established plan.

  According to another variant, also comprising at least a secret memory, the medium provides, when requested directly or by a media reader, only a limited amount of data, preferably only data -12- allowing question the authority which manages the use of said medium after which, in the planned course of the exchange, the authority sends to said medium particular data which is preferably the first (s) code (s) available ( s) at least one list of codes which can preferably only be accessed by one code at a time under the conditions described above, recorded in at least one memory of said medium so that the latter continues the progress of the exchange as soon as he recognized this data. When this data is recognized as coming from the authority, the medium provides data allowing the authority to authenticate it. This variant in the use of code lists avoids by extracting a code from the medium having the possibility of

  divert it by simple interrogation of a media reader.

  If the data supplied to the medium, to open an exchange, by the authority does not correspond to that which it is expected to receive, said medium does not continue the exchange. Aside from the cases of operating anomalies due to hardware failures, such a configuration is certainly the consequence of a false authority trying to break into the authentic speakers. A new attempt is preferably possible but the number of unsuccessful attempts authorized for the same operation or for successive operations is limited; after having exhausted this number of attempts, said support refuses the exchange and the communication of the first code provided, remains closed to any subsequent exchange and the carrier must physically approach the authority to find the cause of this situation and ensure let the support work or get another support. Preferably said support is reusable after a period of time which allows the wearer and the authority to determine the nature of the

problem during the last exchange.

  The hacking attempt is thus defeated: Examples: assuming a support having a single list of accessible codes as described above, for understanding let us assign to each code at the beginning of this list a number from 1 to 3. If the hacker tries to 'intercept codes to access an exchange this happens as follows: 1) the pirate, connected to the network or to a telephone line interrogates the support as if he were the authority, not knowing the code n 1 that must provide l authority to continue the exchange, the support does not continue the exchange, the hacking attempt stops there (preferably this attempt is signaled to the authority at the next exchange with the authority by the support which recorded the 'incident). 2) the hacker, connected to the network or to a telephone line, interrogates the authority -13- as if it were an authorized medium; the authority sends code 1 to the pirate (believing it to be addressed to an authentic medium); with this code n 1 the hacker intercepts a beginning of exchange with the authentic support (which is already difficult), addresses the code n l1 to him; the support recognizes the code and sends the code n 2 in return as an authentication vis-à-vis the real authority; the hacker then has the codes n 1 and n 2 which he then sends to the authority as coming from an authorized medium and in order to carry out a complete exchange, a

criminal transaction ...

  - but the code n "1 having already been exchanged by the authority in a previous exchange, is no longer valid, the authority will ask the support (which in this case is the pirate) to send him the code n 3 that the hacker doesn't have and

  the exchange will neither be certified nor continued.

  - the hacker can start again his attempt to obtain the following code but each time he will miss the last code; after a number of such attempts, preferably, the authority's computer system

  signals that there is an attempted intrusion by such medium.

  In an operating mode even more difficult to penetrate, several codes are exchanged, sent alternately by the participants before a

  effective mutual authentication.

  According to another variant, also comprising at least a secret memory, the medium provides, when requested directly or by a media reader, only a limited amount of data, preferably only data making it possible to interrogate the authority which manages the use of said medium after which, in the planned course of the exchange, the authority sends to said medium specific data as for the previous variant but here the codes, which are extracted one by one or by group ( s), are arranged in at least one list in a random manner or arranged or ordered according to certain criteria, the action of alternately addressing a code (s) being done at least once, additional data are addressed in a single exchange with the corresponding codes or in another exchange or fragmented in several exchanges, said additional data indicating the position of said codes in said list (s) (s) and / or their number (s) or (their) contact details and / or their marker (s) allowing comparison with at least one corresponding code in at least a second list, identical to said / said list (s), stored in the computer system of said authority or

from at least one other entity.

  According to another variant, to the authentication of the support is added, preferably, the identification of the carrier, that is to say his identification as a carrier

authorized from a specific medium.

  A first means of identification consists of an identity photo integrated into the support inseparably, which allows identification for an exchange on the spot, for example during a payment at a merchant, ant. A device making it possible to enlarge this photo, for example to the real size of the face, is available to the merchant, or to another controller, either by inserting or presenting the support in front of this device, or while the

  media is in the media player in order to make a payment, for example.

  Other means allow identification of the wearer on site but also remotely such as a specialized reader to identify the bottom of the eye, a fingerprint or a genetic code from, for example, saliva or carrying out a voice recognition which recognizes the words and identifies the wearer by comparison with memorized voices; these means are safe for identifying an individual but the data representing this identification can be hacked in order to be used unlawfully, which is why, preferably, this identification is added to the authentication of the support to form a secure set. Said specialized reader can be an integral part of the support

  at least for the part used for identification.

  To the support is preferably added at least one secondary device associated with the

  support operation during an exchange or initiating an exchange.

  The intervention of said secondary device is essential for the functioning of the

  support without which this one does not exchange whatever the external request.

  Preferably each use of the support requires the intervention of said secondary device. Connected to the support, with or without electrical contact, the secondary device is preferably only operating for a predetermined period of time during which the support is either used or primed to be used the necessary time without limitation; beyond this period of time which can be for example a few seconds or a few minutes, said support again requires an intervention of said secondary device to

exchange or initiate an exchange.

  The theft of said support cannot allow its use which must be associated with

that of said secondary device.

  The possession of said secondary device can be assimilated to an identification - to the extent that said secondary device is attached to its owner and can remain secret both in its appearance and in its place of operation; it can be personalized and, preferably, integrated into a completely personal object of the wearer such as a watch, bracelet, pendant, belt, spectacle frame or even be implanted for example under the skin for wearers who

want it.

  The electric current source, rechargeable or not, intended for the operation of the system (s) allowing the intervention of said secondary device with respect to said support, is arranged in the secondary device and / or in the support and / or it does not is present only as an external electrical source, for example in the media reader, and then supplies the assembly when the reader is used; in the case of operation without electrical contact, the electrical supply can also come from an induced current

  used directly and / or stored in said secondary device.

  Some advantages of the device: - in a payment or a telepayment it is the bank or the third party to which the bank has delegated its authority which decides to give or refuse its agreement for an operation. Since it is practically risk-free, a bank can guarantee the proper functioning of the payment and electronic payment system and assume any risk of fraud which is an essential asset for

  increase the number of its customers with regard to this type of payment.

  - a medium as described above cannot be reproduced since the list of

  secret codes is not accessible and without this list the medium cannot be used.

  - unless you choose a new form of media, a specific reader is not necessary; for a payment card, a conventional card reader is sufficient; it is not the reader who ensures security, it is the support and its link with the authority. The device according to the invention is intended to secure exchanges of computer data and in particular payments or electronic payments made from media containing digital information such as credit cards.

  chip payment, digital reading discs.

- 16-

Claims (11)

Claims   1) Device for securing exchanges of computer data with a view in particular to exchanging confidential data and / or making payment (s) on the spot or electronic payment (s) using computer means comprising a support itself comprising a computer system comprising functions allowing, inter alia, to communicate with or without electrical contact with another computer system with which it can exchange data, for example with the computer system of the authority which manages the use supports such as said support and / or another entity in connection with or without electrical contact with / a means (s) of transmission and / or processing of computer data necessary (s) for at least one exchange, at minus a secret zone in the system of said medium, inaccessible to transform its operation or to extract data therefrom other than that which it is intended that this zone can provide, at least a secret memory whose operation cannot be transformed nor extract from it data other than that which it is intended that this memory can provide or extract this data otherwise than it is intended to provide it, characterized by the fact that said secret memory associated with said secret zone makes it possible to store data in the form of codes used for authentication of said medium by said authority or by another entity and / or for mutual authentication between two entities using computer means one of which may be a medium such as said medium, the term "code" designating at least one word, in the computer sense, and / or at least one algorithm and / or an assembly of digital data in any form whatsoever, making it possible to identify or be identified, during an exchange, by its appearance, its shape which can be compared to an assembly of witness digital data, said codes being dis preferably placed in at least one list inaccessible to consultation once it is entered in said secret memory except for the first code (s) of said list which can be used for preferably once and only once, to secure an exchange, after which it (s) is (are) discarded (s) or erased (s) or made (s) inaccessible (s) and this is the code (s) ( s) following (s) of said list which is (are) the only (s) to be consulted, used (s) as code (s) for the same exchange or for another exchange, -17- said codes, preferably succeeding one another unpredictably for an observer outside the confidentiality of their composition and arrangement, being designed and preferably arranged randomly by software and preferably it is the same software which creates at least a second list identical to said list written in said medium, said second list being put e stored in the computer system of said authority or at least one other entity in order to allow comparison   at least one code to the corresponding code in the other list.   2) Device for securing the exchange of computer data with a view in particular to exchanging confidential data and / or making payment (s) on the spot or electronic payment (s) using computer means comprising a support itself comprising a computer system comprising functions allowing, inter alia, to communicate with or without electrical contact with another computer system with which it can exchange data, for example with the computer system of the authority which manages the use supports such as said support and / or another entity in connection with or without electrical contact with / a means (s) of transmission and / or processing of computer data necessary (s) for at least one exchange, at minus a secret zone in the system of said medium, inaccessible to transform its operation or to extract data therefrom other than that which it is intended that this zone can provide, at least one secret memory, the operation of which cannot be transformed or extract data other than that which it is intended that this memory can provide or extract this data otherwise than it is intended to provide it, characterized by the fact that said secret memory associated with said secret zone makes it possible to store data in the form of codes used for authentication of said medium by said authority or by another entity and / or for mutual authentication between two entities using computer means one of which may be a medium such as said medium, the term "code" designating at least one word, in the computer sense, and / or at least one algorithm and / or an assembly of digital data in any form whatsoever, making it possible to identify or be identified, during an exchange, by its appearance, its shape which can be compared to an assembly of witness digital data, said codes being preferably arranged in at least one list inaccessible to consultation once it is entered in said secret memory except for one or more codes extracted one by one or by group (s), to which codes are associated additional data indicating the position of said codes in the list (s) and / or their number (s) or their contact details and / or their marker (s) in order to allow comparison with at least one corresponding code in at least a second list, identical to said list, stored in the computer system of said authority or of at least one other entity, said codes being arranged randomly or arranged or ordered according to certain criteria, said complementary data associated with codes being addressed in a single exchange with the corresponding codes or in another exchange or fragmented in several exchanges, said codes being chosen randomly or according to a plan established or according to a plan established during an exchange, this plan being contained in at least one secret zone of the support system and at least in the computer system of the authority or entity with which said support must carry out a   authentication or mutual authentication.   3) Device according to any one of the preceding claims   characterized in that at least one list of codes of said medium, contained in at least one secret memory, is supplemented or replaced by at least one algorithm which creates usable codes like those of said list, said creation being made progressively the use of said medium and the elimination of the codes used as intended, at least one algorithm installed in the computer system of said authority or of at least one other entity creating the same codes to compare them with those of said medium allowing '' authenticate said support during an exchange between said support and said authority and / or another entity, and / or allowing mutual authentication between said support and said authority   or said entity and / or mutual authentication between two entities.   4) Device according to any one of the preceding claims,   characterized by the functions of association and dissociation by the system of said medium and / or by the computer system of the authority and / or by at least one other determined entity, of at least one code of at least one list of said support - 19- to the data exchanged during an exchange other than that of authentication with a view to coding said data or additional coding if these   data is already coded or encrypted, and vice versa.   5) Device according to any one of the preceding claims,   characterized in that said medium can only be used with a small number of computer hardware such as computers or media players or peripherals for connection to at least one network, and preferably with only one of these materials, with which (which ) he must carry out a reconnaissance   or mutual authentication before it can be used.   6) Device according to any one of the preceding claims, characterized   in that each use of the medium is subject to the introduction into the system of said medium and to its acceptance of at least one personal code specific to said medium and to the authentic bearer of said medium, said personal code being wholly or partly variable in the time, the variations being secret except for   said carrier and possibly the authority which delivers said support.   7) Device according to any one of the preceding claims,   characterized in that when a particular code is used, said code triggers the blocking of the use of said medium in the computer system   authority, either permanently or provisionally.   8) Device according to any one of the preceding claims,   characterized by the association with the operating system of an assistant device producing at least one signal which may be a clock signal which is associated with all or part of the data of an exchange, the computer system of said authority detecting, in an exchange thanks to said assistant device, any anomaly in the exchange of data which may indicate a modification of the data themselves.   9) Device according to claim 8 characterized in that the characteristics of said signal (said signals) vary in the same exchange and / or for each exchange, the modes of variation being preferably in memory and inaccessible in said medium and in said computer system of said authority. -20 -   ) Device according to any one of the preceding claims,   characterized in that said medium provides, when requested directly or by a medium reader, only the data making it possible to interrogate said authority which manages the use of said medium or at least one other entity, said authority or said entity having to send specific data to said medium so that the exchange can continue, failing which said medium does not continue the exchange, this particular data preferably being: - either the first code (s) d '' at least one list of codes registered in at least a secret memory of said support, inaccessible, except to access the first code (s) and only under the conditions described in claim 1, - either one / code (s) extracted one by one or by group (s) from at least one list of codes recorded in at least one secret memory of said medium and additional data indicating their position in the list (s) and / or their number (s) or their (their) coordinates and / or its (its) / their reference (s), said additional data being able to be addressed in a single exchange with the corresponding codes or in another exchange or fragmented in several exchanges, in order to allow the comparison with at least one code corresponding in at least a second list, identical to said list, stored in the computer system of said authority or of at least one other entity, said codes being arranged randomly or arranged or ordered according to certain criteria, said codes being chosen randomly or according to a pre-established plan or according to a plan established during an exchange, this plan being contained in at least one secret zone of the system of said support and at least in the computer system of said authority or said entity, after having recognized said particular data and authenticated the sender, said medium in turn sends data to said authority or to said entity in order to be authenticated in turn, the action of alternately addressing codes being done at least once, the exchange can then continue between the two mutually authenticated entities, in the event of an authentication failure, a   retrying is possible, the number of attempts preferably being limited.   11) Device according to any one of the preceding claims,   characterized in that the identification of the carrier of a support such as said support is made by means of a secondary device essential for the use of said support -21 - before or during a data exchange or the initiation of an exchange , with or without electrical contact with said support, said secondary device preferably being integrated into a personal object of said carrier and all in a place which may only be known to said carrier even during the use of said device secondary.   12) Device according to any one of the preceding claims   characterized by an operating system which uses at least one medium such as said medium, alone or in combination with other means such as the computer system of an authority and / or another entity and / or means of transmission and processing of computer data necessary for an exchange.