EP3198546A1

EP3198546A1 - Transaction method

Info

Publication number: EP3198546A1
Application number: EP15771857.8A
Authority: EP
Inventors: Caroline Grosser
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient Mobile Security GmbH
Priority date: 2014-09-24
Filing date: 2015-09-22
Publication date: 2017-08-02
Also published as: US20180232727A1; US10839380B2; DE102014014109A1; WO2016045788A1

Abstract

The invention relates to a method for anonymously making a transaction. In said method, one-time passwords encrypted using a one-way function are sent from an authentication server (12) to a service device (16). The non-encrypted one-time passwords are sent by the authentication server (12) to a secure element (10) of a mobile device. In order for a transaction to be made, the secure element (10) sends the one-time passwords to the service device (16).

Description

transaction process

Technical Field The present invention relates to a transaction method. In particular, the present invention relates to a method for anonymous

Perform a transaction.

When conducting online transactions, users sometimes wish to have their identity protected or hidden from a service provider in which they use a service.

A service used may be, for example, the acquisition of a music file and / or a text document.

State of the art

From DE 10 2011 119 103 AI a method for authenticating a person to a server instance is known, the person as

Authentication agent uses a disk.

Furthermore, in the prior art so-called

Authentication service known, which perform as a service the authentication of a person for a service, such as a cloud service. Such authentication service providers are also known as "Authentication as a Service Providers" (AaaS) .Overhead for a cloud service claiming an authentication service provider is that it is no longer necessary for authentication

Security requirements must take care of. This is done by the

Authentication service provider for him. Furthermore, in the prior art, fee-based services are known which charge on the basis of the number of accesses or the duration of access.

Such services require that users be required to charge a credit account with the service. The credit account is necessary because the settlement of small amounts due to the high transaction fees is generally unattractive. Creating the credit account at the service requires the user to reveal their identity. Only so is a secure association between

Credit balance and users possible. For users of such

paid service, however, it is annoying, always one in advance

Deposit amount to the service to then take this credit amount gradually to complete.

Furthermore, an anonymous payment method is known from the prior art, in which the user buys a credit card with a PIN with cash, wherein this PIN is assigned a corresponding amount of money. With this prepaid card (for example, a PaysafeCard), it is possible to anonymously pay a sum of money by the PIN of the prepaid card is entered for payment.

In summary, the cited prior art has the disadvantage that there is no payment method with which it is anonymously possible to pay small amounts. Because even with the anonymous payment method with the prepaid card, it is always necessary to pay a certain minimum amount. In addition, the user is usually not willing to enter his PIN for paying small amounts. Presentation of the invention

It is an object of the present invention to provide a method of anonymously performing a transaction which overcomes the known problems of the prior art and which is further adapted to enable secure and anonymous payment of both large and small amounts.

The object is achieved by a method according to

The subject of claim 1. Preferred embodiments of the method according to the invention will become apparent from the dependent claims.

The invention is based on the idea of providing an authentication server as a link between a secure element, a payment device and a service device such that it is possible with the secure element to make an anonymous payment at the service device.

Accordingly, the method of anonymously performing a transaction comprises establishing a first connection between a secure element and an authentication server, establishing a second connection between the authentication server and a payment device, transferring an amount of money from the secure element to the payment via the authentication server Means, generating at least one one-time password (OTP), wherein the number of one-time passwords corresponds to the transferred amount of money, and sending the at least one one-time password

(at least) a service device via a third connection, wherein the One-time password is sent only after it has been encrypted with a one-way function.

A "secure element" is a unit in a mobile device in which data can be stored in a particularly secure manner The secure element can have different form factors For example, the secure element can be a chip permanently installed in the mobile device, a SIM card and / or or a (micro-) SD card According to the invention, the "mobile device" is, for example, a mobile phone, a tablet PC or the like. The mobile device is provided with an interface, in particular with a contactless interface, for example via GSM and / or WLAN, and / or a contact-type interface.

An "authentication server" in the sense of the invention is used to authenticate a user to another service, such as the payment device and / or the service device. [Weitere Weitere] Other tasks of the authentication server can be: care of several different service devices,

Decryption of received data, payment of one-time passwords at the payment facility, verification of payment (successful redemption), generation of one-time passwords (OTPs), treatment of one-time passwords with the one-way function (eg hash), buffering of one-time passwords lists (OTP | hash) OTP)), assignment of the

One-time passwords to the corresponding desired service device, transmission of the one-way function-treated one-time passwords (hashed OTPs) to the corresponding desired service device, Encrypting the one-time passwords (eg with a public key of the secure element), transmission of the encrypted original one-time password list to the secure element In a "payment device", a user can preferably make a payment anonymously Transfer money to the payment facility of a PaysafeCard Alternative payment methods such as a prepaid credit card or the like are also possible.

Under a "service facility" within the meaning of the invention is a

Understood institution for which the anonymous payment is intended. In return, the service facility provides a service upon receipt of the payment. Of course, it is possible for an amount once paid to the payment facility to be used to service a variety of service facilities. It is also possible that the amount may be used in a single service facility to account for a variety of different

Services / goods to pay.

With the method according to the invention it is particularly advantageous possible to provide an anonymous payment method, since the

Service facility and the payment device are independent of each other. Furthermore, it is not necessary for the authentication server to permanently store the one-time passwords and / or the one-way passwords encrypted with the one-way function. Because the one-time passwords can be stored in the secure element and those with the

One-way function encrypted one-time passwords can be used in the

Service device to be stored. Furthermore, the Security requirements for the service device is not particularly high, since it is only necessary in this store the encrypted using the one-way passwords. If someone is the

However, it is necessary to contact the service provider

Service means the original one-time password, i. without being encrypted with the one-way function to transmit.

The one-way function is a hash function according to one embodiment. Such hash functions are known in cryptology and are characterized, inter alia, by the fact that it is practically impossible to find an input value for a given output value. In other words, it is relatively easy to get out of one

known input value to calculate an output value. The reverse case, ie the calculation of an input value from an output value, is practically impossible. Thus, it can be ensured that only the one who can redeem the amount of money in the service, which is in knowledge of at least one original one-time password. It is not sufficient to transmit the hash function hashed one-time password to the service facility.

To further increase security, the one-time password may be preceded by a random string before being encrypted. This method is also referred to as "cold" in cryptology, and describes a method in which the randomly chosen string is appended to the one-time password prior to applying the hash function. Using the random string in conjunction with the hashing function increases the security of the method additionally.

Furthermore, the generated one-time passwords may have an expiration date be provided in order to limit the access to the service of the service device in time.

According to a further particularly preferred embodiment, the payment device confirms after receipt of the amount of money from the secure element (via the authentication server) the receipt of the amount of money at the authentication server. In this way, the arrives

Authentication server informed that the payment device has received the amount of money and thus the

Authentication server can have this amount. Furthermore, the service facility is informed by the authentication server of the payment received since the authentication server is aware that payment has been made. The actual transfer of money to the service facility can be done by methods known in the art.

According to another embodiment, the

Authentication server that at least one one-time password to the secure element, wherein the transmission of the one-time password to the secure element can preferably be encrypted. The at least one one-time password is sent to the secure element without being encrypted with the one-way function. In this way, the secure element is aware of the "original" one-time password and can use it to call a service at the service facility, thus authorizing a secure and easy one

Transaction allows.

Furthermore, according to a further particularly preferred embodiment, the at least one one-time password is generated by the authentication server. This way, the authentication server, after he has been informed that the payment device has received the amount of money to start generating the one-time passwords. This increases the security of the transaction process, since the payment device has no knowledge of the one-time passwords.

Furthermore, the authentication server can make a list with the

One-time passwords and passwords encrypted with the one-way function. The provision of such a list can advantageously serve to ensure an association between the passwords and the passwords encrypted with the one-way function.

According to a further particularly preferred embodiment, the authentication server sends the at least one one-time password encrypted with the one-way function to the service device via the third connection. In this way it is ensured that the service device receives the one-way function encrypted one-time passwords directly from the authentication server.

According to another embodiment, the number of passwords may correspond to the amount of money. In this way, it is possible to divide a once paid to the payment facility amount of money in any number of individual amounts and assign each item a one-time password. It is possible that a one-time password always equals an equal amount of money, for example, two cents. Alternatively, it is possible for each one-time password to have a different height

Amount of money equals. In this way can be different

Denominations are more easily realized. According to one embodiment, the service device has a list of one-way function encrypted and unused one-time passwords. These unused one-time passwords are used to pay a monetary amount to the service facility. For this purpose - according to another embodiment - the secure element sends a non-encrypted with the one-time function

One-time password (from the list of not yet used

One-time passwords) to the service facility. In this way, a particularly simple and reliable payment method is realized, since it is only necessary for the payment of an amount, one not yet encrypted with the one-time function one-time password to the

To send service facility. To check if it is at the

Once the password is a valid one-time password that has not yet been consumed, the service device applies the one-way function to the password. In the event that the two passwords to which the on-away function has been respectively applied agree, the service facility recognizes that a valid payment intent exists and allows the requested service to be claimed from it. In order to pay a higher amount at the service facility, according to one embodiment, it may be necessary to have several

One-time passwords (to which the on-way function has not been applied) are transmitted to the service facility. The number of transmitted one-time passwords then corresponds to the amount to be paid. Brief description of the drawings

Fig. 1 shows a schematic sequence of an inventive

Geldaufladeverfahrens,

Fig. 2 shows a schematic sequence of an inventive

Payment procedure, and

Fig. 3 shows a sequence of a method according to the invention.

Detailed description of preferred embodiments of the invention

Below is a description of the method according to the invention with reference to purely exemplary embodiments with reference to the accompanying figures 1 to 3.

In this connection, Fig. 1 shows schematically a procedure when transferring a sum of money from a secure element 10 to a payment device. For this purpose, first a first connection 20 is established between the secure element 10 and an authentication server 12 via an air interface (GSM / WLAN). The secure element 10 notifies the authentication server 12 of its intention to pay a cash amount to a payment facility (payment facility) 14. Subsequently, the authentication server 12, against which the secure element 10 has authenticated, establishes a second connection 22 with the payment device 14. The second connection 22 may be constructed by known methods.

Subsequently, the amount of money is transmitted from the secure element 10 via the authentication server 12 to the payment device 14. To ensure anonymity when paying the amount can For example, a prepaid credit card or other anonymous payment method such as a PaysafeCard may be used to pay. As soon as the amount has been paid to the payment device 14, the payment device confirms the receipt of the amount of money at the authentication server 12.

As soon as the authentication server 12 has been informed about the receipt of payment by the payment device 14 by means of the second connection 22, the authentication server 12 generates one-time passwords in accordance with the amount of the paid-in amount. If, for example, 10 euros were transferred to the payment facility, then the

Authentication server with a denomination of 2 et / password a total of 500 one-time passwords. The person in the knowledge of these one-time passwords can use them to pay for or to use a service 16 at authorized service facilities.

The one-time passwords are subsequently used by the

Authentication server 12 with a one-way function, such as a hash function, encrypted. To further increase security, the one-time passwords may be supplemented with a random string before being encrypted. This approach is also called "strings" in cryptography

One-time passwords have a limited validity. Depending on the desire of the user of the secure element 10, all one-time passwords encrypted with the one-way function are sent to a service device 16 or to a plurality of different ones

Services 16 transferred. Then the service device 16 is aware of the one-way function encrypted one-time passwords and the authentication server is aware of both the

One-time passwords as well as one-way passwords encrypted with the one-way function.

One-time passwords are then transmitted to the secure element 10. So that the transmission of the passwords from the authentication server 12 to the secure element 10 via the first connection 20 is secure, the first connection 20 may be a secure connection.

The secure element 10 is in possession of the one-time passwords after transmitting the one-time passwords. To a paid service of

To use the service device 16, it is necessary that "original" one-time passwords are transmitted from the secure element 10 to the service device 16 according to the amount of the usage fee

illustrates this process.

First, a fourth connection 28 is established between the secure element 10 and the service device 16. The secure element 10 sends a one-time password to the service device 16. The service device 16 applies the one-way function to the one-time password sent by the secure element 10. Subsequently, the service device 16 checks whether it is stored with a one-way function encrypted one-time password that matches the password just encrypted with the one-way function. Conversely, if a match of the passwords is detected, this means, conversely, that the one-time password has not yet been used and, consequently, this can be used to make use of the service 16. Depending on the amount of the required for the use of the service facility 16 Amount of money, several "original" one-time passwords may be sent to the service facility 16 from the secure element 10. The number of one-time passwords corresponds to the amount of payable

Monetary amount.

FIG. 3 shows a flow chart which shows the sequence of the

represents the inventive method. In this method, in a first step S1, as already explained above, a first connection 20 is established between a secure element 10 and an authentication server 12. Subsequently, in a second step S2, a second connection 22 between the authentication server 12 and a payment device 14 is established. Once these two links 10, 12 have been made, a monetary amount is transferred from the secure element 10 to the payment device 14 via the authentication server 12.

The payment device 14 confirms in a subsequent step S4 the receipt of the amount of money at the authentication server 12.

In a next step S5, the authentication server 12 generates at least one one-time password, the number of one-time passwords corresponding to the amount of money transferred to the payment device 14.

In a next step S6, the authentication server 12 sends the at least one one-time password to a service device 16 via a third connection 24, wherein the one-time password is only sent after it has been encrypted with a one-way function (hash function). In parallel thereto or subsequently, in an optional step S7, the "original" one-time passwords can be sent to the secure element 10. The conclusion of the transaction takes place, as shown in Fig. 2, by the secure element 10 via a fourth connection 28, which can be built analogously to the first connection 20, one of the transmitted in step S7 passwords to the service device 16. The passwords can be stored in the secure element. This makes it difficult for third parties to illegally access the passwords in the secure element 10. By applying the one-way function to the one-time password sent from the secure element 10 to the service device 16 by the service device 16, the service device 16 can check whether the one-time password has already been used

One-time password is valid. If it is a valid password, then after applying the one-time function to the

One-time password a match with a stored at the service device 16 password. In case of a match, the service of the service device 16 can be used by the secure element 10.

When applying the one-way function before sending the one-time passwords via the third connection 24 to the service device 16, the

Authentication server 12 verify that password duplication occurs after applying the one-way function. Should

Password duplications result, the authentication server 12 generates another one-time password and applies the one-way function to this new one-way password.

Claims

Patent claims

A method for anonymously executing a transaction, comprising the following steps:

Establishing a first connection (20) between a secure element (10) and an authentication server (12),

- Establishing a second connection (22) between the

Authentication server (12) and a payment device (14),

Transferring an amount of money from the secure element (10) via the authentication server (12) to the payment device (14),

Generating at least one one-time password, wherein the number of one-time passwords corresponds to the transferred amount of money, and

- Sending the generated one-time passwords to a service device (16) via a third connection (24), wherein the at least one one-time password is sent only after it has been encrypted with a one-way function.

2. Method according to claim 1, characterized in that the one-way function is a hash function.

3. The method according to claim 2, characterized in that the one-time password before encrypting with a randomly selected

String is provided.

4. The method according to any one of the preceding claims, characterized in that the payment device (14) in the

Authentication server (12) confirms the receipt of the money.

5. The method according to any one of the preceding claims, characterized in that the authentication server (12) sends the at least one one-time password to the secure element (10), wherein the transmission is preferably encrypted.

6. The method according to any one of the preceding claims, characterized in that the authentication server (12) generates the at least one one-time password.

7. The method according to any one of the preceding claims, characterized in that the authentication server (12) has a list with the one-time passwords and the one-way function encrypted one-time passwords.

8. The method according to any one of the preceding claims, characterized in that the authentication server (12) sends the at least one one-time password to the service device (16) via the third connection (24).

9. The method according to any one of the preceding claims, characterized in that the number of one-time passwords corresponds to the amount of money.

10. The method according to any one of the preceding claims, characterized in that the service device (16) a list of encrypted with the one-way function and not yet used

Having one-time passwords.

11. The method according to any one of the preceding claims, characterized in that to complete a transaction, the secure element of a mobile device (10) sends at least one non-encrypted with the one-time function one-time password to the service device (16).

12. The method according to claim 11, characterized in that the service device (16) the one-way function sent to the

Applies one-time passwords.

13. The method according to claim 11 or 12, characterized in that the number of sent one-time passwords one to the

Service facility (16) corresponds to the amount of money to be paid.