EP2553864A1

EP2553864A1 - Method for associating a first data carrier unit with a second data carrier unit

Info

Publication number: EP2553864A1
Application number: EP11712176A
Authority: EP
Inventors: Gisela Meister; Dieter Weiss; Klaus Finkenzeller; Florian Gawlas; Jan Eichholz
Original assignee: Giesecke and Devrient GmbH
Current assignee: Giesecke and Devrient Mobile Security GmbH
Priority date: 2010-03-29
Filing date: 2011-03-25
Publication date: 2013-02-06
Also published as: WO2011124334A1; DE102010013201A1

Abstract

The invention relates to a method for associating a first data carrier unit (1) with a second data carrier unit (2). In the method according to the invention, a first cryptographically secured channel (K1) is established between the first data carrier unit (1) and a terminal computer (T) on the basis of a first piece (A) of cryptographic information. Furthermore, a second cryptographically secured channel (K2) is established between the second data carrier unit (2) and the terminal computer (T) on the basis of a second piece (B) of cryptographic information. Subsequently a third piece (C) of cryptographic information is determined on the basis of the first and/or second piece (A, B) of cryptographic information in the terminal computer (T) and transferred by the terminal computer (T) to the first and/or second data carrier unit (1, 2) by means of the first and/or second cryptographically secured channel (K1, K2) so that the third piece (C) of cryptographic information is available to the first and second data carrier units (1, 2), wherein a third cryptographically secured channel (K3) can be established between the first and second data carrier units (1, 2) by means of the third piece (C) of cryptographic information.

Description

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The invention relates to a method and a system for allocating a first data carrier unit to a second data carrier unit.

In many technical fields of application, it is desirable to establish a protected communication connection between a first data carrier unit and a second data carrier unit. These data carrier units are preferably portable data carriers, in particular with corresponding security functionalities, such as e.g. Smart Cards. The data carrier units may also comprise contactlessly communicating readers, e.g. RFID readers, or so-called terminals, which can communicate with other data carrier units contactless or contact-bound. Such readers or terminals often contain corresponding security elements or security modules, such as e.g. a secure element or a SAM module (SAM = Secure Application Module).

For cryptographically secured Korrurinikation between two disk units usually a complex PKI infrastructure (PKI = Public Key Infrastructure) is required to perform based on corresponding certificates, such as CV certificates, an authentication between the disk units to establish a secure communication.

The object of the invention is therefore to easily allocate two data carrier units to one another in such a way that they can communicate cryptographically secured with one another with high performance. This object is achieved by the measures described in the independent claims. Further developments of the invention are defined in the dependent claims.

In the method according to the invention, a first, cryptographically secured channel based on a first cryptographic information is set up between a first data carrier unit, which is preferably a portable data carrier unit, and a terminal computer. Furthermore, a second cryptographically secured channel based on a second cryptographic information is set up between a second data carrier unit, which in turn is preferably a portable data carrier unit, and the terrninal computer. The structure of the two channels can be done with any known from the prior art, for example, based on protocols for data exchange between a data carrier unit in the form of an electronic identity document and a corresponding terminal. Such protocols are described, for example, in documents [1] and [2]. Subsequently, a third cryptographic information is determined based on the first and / or second cryptographic information in Terrninalrechner. For example, this cryptographic information can be generated from a suitable combination of the first and second cryptographic information, in particular via an XOR link. This third cryptographic information is then transmitted from the terminal computer to the first and / or second data carrier unit via the first and / or second cryptographic information transmitted second cryptographically secured channel so that it is the first and second volume unit available. This third cryptographic information can be followed by a third cryptographic information. tographically secured channel between the first and second volume unit.

The communication between the first and second data carrier unit is done directly and without intermediate units, such as the terminal computer. Coir communication is local between both volume units and limited to the volumes of the volume units.

According to the invention, a third cryptographic information is generated via a protected communication of the respective first and second data carrier with a terminal computer, which is then provided to the first and second data carrier unit for establishing a secure channel between these units. It is thus easily achieved a pairing between two data carrier units, without the need for a complex infrastructure must be used.

In a particularly preferred embodiment of the inventive method, the first data carrier unit negotiates with the terminal computer a first cryptographic key via which the first cryptographically secured channel is established. Analogously, the second data carrier unit with the TerrrLinalrechner a second cryptographic key, over which the second cryptographically secure channel is established. For negotiating the keys, methods known from the prior art can be used again. For example, the Diffie-Hellmann key exchange can be used to generate the first and second cryptographic keys, respectively. Preferably, the terminal computer derives from the first and second cryptographic keys a third cryptographic key which is transmitted via the first cryptographically secured channel to the first data carrier unit and via the first cryptographic key second cryptographically secured channel is transmitted to the second data carrier unit.

In a further variant of the method according to the invention, the terminal computer is a signature terminal known from the prior art for electronic identity documents, the so-called secure messaging connecting the first and / or second cryptographically secured channel between the signature terminal and the first and / or second data carrier unit, which are each electronic identity documents, is constructed. The Secure Messaging is preferably based on a password-based transport protocol and more preferably based on the PACE protocol (see documents [1]).

In a further, particularly preferred embodiment of the invention, in the method a first and / or second data carrier unit with a contactless and / or contact-type interface, e.g. with a USB interface or an NFC interface. In particular, the first and / or second data carrier unit is a chip card, preferably a smart card, and / or a token and / or a reader and / or an electronic identity document with a person's machine-readable identification data stored on a chip. The contactless and / or contact-type interface of the first data carrier unit is used to construct the first cryptographically secured channel, whereas the contactless and / or contact interface of the second data carrier unit is used to construct the second cryptographically stored channel.

In a further embodiment of the method according to the invention, a terminal computer with a contactless interface (eg an NFC interface) is used. Stelle) and / or a contact-type interface (eg USB interface) used. In this case, the contactless and / or the contact-type interface are used to construct the first and / or second cryptographically secured channel. Optionally, the terminal can also have a plurality of contactless or contact-type interfaces, which are used in a suitable manner for the construction of the first and second cryptographically secured channel.

In a variant of the method according to the invention, the first cryptographically secured channel is constructed directly between the contactless interface of the terminal computer and the contactless interface of the first data carrier unit, and the second cryptographically secured channel is directly between the contact interface of the primary computer and the contact-based terminal built the second volume unit.

In another embodiment, the first cryptographically secured channel is established between the contact interface of the terminal computer and the contactless interface of the first data carrier unit via the contact interface of the second data carrier unit and the contactless interface of the second data carrier unit, whereas the second cryptographically secured channel directly between the contact interface of the terrestrial computer and the contact-based one

Interface of the second volume unit is built. This variant of the invention is used when the terminal computer has no contactless interface.

In a further embodiment of the method according to the invention, the first cryptographically secured channel is directly between the contactless Interface of the terminal computer and the contactless interface of the first data carrier unit constructed, whereas the second cryptographically secured channel is constructed directly between the contactless interface of the terminal computer and the contactless interface of the second data carrier unit. This variant of the invention is used when the terminal computer has only one contactless interface.

In a further embodiment of the method according to the invention, the terrestrial computer is a terminal server which is connected via a secure Internet connection and / or a VPN connection to a computer to which the second data carrier unit is connected via its contact-type interface. In this case, the first cryptographically secured channel is established between the terminal server and the contactless interface of the first data carrier unit via the computer connected to the terminal server and the contact-based and contactless interface of the second data carrier unit, whereas the second cryptographically secured channel between the terminal server and the contact-type interface of the second Data carrier unit is established via the computer connected to the terminal server. As a result, terminals arranged in the form of terminal servers remote from the first and second data carrier units can be included in the method according to the invention.

In a further variant of the method according to the invention, the second data carrier unit is a radio device, in particular a mobile device, with a contactless interface and the terminal computer is again a terminal server, wherein the first cryptographically secured channel between the terminal server and the contactless interface of the first data carrier unit with the interposition of a mobile radio connection or a local radio connection using the radio and over the contactless interface of the radio is built. In contrast, the second cryptographically secured channel is established between the terminal server and the radio with the interposition of a cellular connection or a local radio connection using the radio. This variant of the invention also makes it possible to use terminals in the form of terminal servers arranged remotely from the first or second data carrier unit.

In addition to the method described above, the invention further relates to a system of terminal computer, first data carrier unit and second data carrier unit, which is configured such that during operation of the system, the inventive method and in particular one or more preferred variants of this method are feasible. Embodiments of the invention are described below in detail with reference to the accompanying drawings.

FIG. 1 shows a first embodiment of a device according to the invention. FIG

Method based on two data carrier units in the form of smart cards;

Fig. 2 to Fig. 4 further embodiments of the invention

A method based on a first data carrier unit in the form of a smart card and a second data carrier unit in the form of a reader or a mobile telephone; 1 shows a first embodiment of the inventive method in which a first data carrier unit 1 in the form of a smart card (ie a smart card with security functionality based on secure secret data) and a second data carrier unit 2, also in the form of a smart card, via a terminal T communicate with a SAM module 3 (SAM = Secure Application Module). There is also the possibility that the first data carrier unit or the second data carrier unit are not designed as smart cards, but as other portable devices. In particular, the first and / or second data carrier unit may be a token, for example. In one variant, the smartcard 1 and the smartcard 2 can have a contactless NFC interface and communicate therewith with the terminal T, which in this case represents an RFID reader. Both cards are supplied with voltage via the RFID reader. In a further variant, the smart cards in addition to the contactless interface also comprise a contact-type interface and can communicate with the terminal T via a provided with the terminal contact-type interface with this. Preferably, the two smart cards 1 and 2 are also designed such that they can communicate with each other directly without interposition of the terminal via their contactless interfaces.

The aim now is to store cryptographic information in both the smartcard 1 and in the smartcard 2, which enables the establishment of a secure channel between these two smartcards at a later time. To achieve this, the smart card 1 negotiates a symmetric session key A with the terminal T as part of the construction of a first cryptographically secured channel K1. It can be used from the prior art known methods for negotiating the key (eg, a Diffie-Hellmann key exchange), in particular based on secure messaging, as described in document [1] or [2]. In particular, a password-based or asymmetric transport protocol (eg the PACE protocol known from the prior art) can be used. Thus, a key A between terminal T and smartcard 1 is generated, which is available in terminal T. In an analogous manner, a second session key B is generated with the same mechanism as part of the construction of a second secure channel K2 between smart card 2 and terminal T, which is likewise available in the terminal T. In a preferred variant, when generating the corresponding key, a card identifier of the smartcard 1 or the smartcard 2 is used, which does not correspond to the identity identifier of the cards. Preferably, a so-called. Restricted IE) is used. The use of a restricted IE) within corresponding authentication protocols is again described in the above-mentioned documents [1] and [2].

After establishing the channels K1 and K2, a further key C is finally derived based on the two keys A and B in the SAM module 3, which uses information from both keys. For example, both keys A and B can be connected via an XOR link and this XOR link then represents the key C. The key C is then stored on the smart cards 1 and 2 via the two secure channels K1 and K2. Thus, both cards have a common secret. In a later usage phase, the key C is then used to establish a secure channel between the two cards 1 and 2. This secure channel can be established independently of the terminal T used in the generation of the key C. That is, in the use phase of the smart cards 1 and 2, a terminal can be used, which does not match with the terminal that at the generation of the session key was used. In particular, in the use phase, no further security mechanisms, such as. PACE protocol and / or complex authentication between the portable data carriers 1, 2 and the terminal T necessary.

1, according to the invention, a one-to-one bond ("pairing") between a first data carrier unit and a second data carrier unit is achieved In the following, further variants are described how such a bond between two data carrier units can be achieved In the embodiments of FIGS. 2 and 3, the first data carrier unit is a smartcard 1 which has at least one contactless NFC interface (not explicitly shown) and optionally also a contact-type interface (not explicitly shown) and in this case a so-called dual On the other hand, in Figs. 2 and 3, as a second data carrier unit 2, a portable reader in the form of a token having a SAM module contained therein (also called a smart reader) is used, the token both via a contact-type USB interface 2a as well as via a contactless NFC interface The terminal T comprises according to Fig. 2 and Fig. 3 several Kommurul ationsschnittstellen towards the smart card 1 and the reader 2 and a SAM module 3. In particular, the terminal T comprises a contactless NFC interface 4, for example establishes a communication via the ISO / IEC 14443 standard or the ISO / IEC 18093 standard. In addition, the terminal T has a contact-type interface 5, preferably USB. The terminal T can, for example, constitute a so-called authorization or signature terminal, which is described in the abovementioned document [1]. The smart card 1 can be designed as an electronic identification document, in particular in the form of an identity card or passport (eg ePA). 2 shows a first embodiment of an inventive embodiment for assigning the smart card 1 to the token 2. In this embodiment, the smart card 1 communicates with the terminal T via a contactless interface of the smart card and a corresponding NFC

Interface 4 of the terminal. Communication takes place, for example, via ISO / IEC 14443 or ISO / IEC 18093 standard. The interface 4 acts as an RFID reader. Furthermore, the USB token 2 communicates with the terminal 4 via the USB interface 2a of the token and the USB interface 5 of the terminal. Based on the communication between smart card 1 and terminal T, a first secure (i.e., cryptographically secured) channel K1 between smart card 1 and terminal T is established by known methods, which have already been mentioned above. In this case, a key A is negotiated, which is the terminal T and the chip card 1 available. Similarly, based on the communication between the token 2 and the terminal T, a second secure channel K2 is set up and a key B is negotiated, which is available to the terminal T. As described above, a key C is then derived from the two keys A and B and provided in each case via the corresponding secure channels K1 or K2 of the smart card 1 or the token 2. Subsequently, smartcard 1 and token 2 can communicate separately with each other via a secure channel K3 using the key C, as stated previously. This communication can take place with the interposition of any terminal. If appropriate, this communication can also take place directly via contactless interfaces in the smartcard 1 and the token 2.

In a second embodiment, which is not pictorially illustrated in FIG. 2, the terminal T has exclusively the USB interface 5. In this case, the communication between the terminal T and the smartcard 1 is routed via the token 2. The token functions as an RFID reader. In this case, an end-to-end encryption is provided between the terminal T and the smartcard 1. The first cryptographically secured channel K 1 is thus constructed between the USB interface 5 and the contactless interface of the smart card 1 with the interposition of the USB interface 2 a and the contactless interface 2 b of the token 2. The second cryptographically secured channel K2 is in turn constructed analogously to the embodiment described above between the USB interface 5 of the terminal T and the USB interface 2a of the token 2.

In a third embodiment, the terminal T has exclusively the contactless NFC interface 4. In this case, the communication between the terminal T and the token 2 takes place via the contactless interface 4 of the terrninal and the contactless interface 2b of the token. The token is designed such that it can communicate with the NFC interface 4 as a passive contactless token, wherein the NFC interface 4 acts as an RFID reader. The cryptographically secured channel constructed via the contactless interfaces 4 and 2b is indicated in FIG. 2 by a dashed line and designated by Kl '.

In a fourth embodiment, which is shown in FIG. 3, the terminal T is located at a location remote from the smart card 1 and the token 2. The terminal T represents a terminal server which is connected via a network IN (in particular the Internet). can communicate with a computer 6 in the form of a PC. In this case, an end-to-end encrypted Internet connection or a VPN connection is established between the terminal T and the USB token 2, which is connected via its USB interface 2 a to a corresponding USB interface of the PC 6. About these connections The second cryptographically secured channel K2 is established between terminal T and token 2. Moreover, the encrypted connection between terminal T and USB token 2 is also used in the context of the construction of the first cryptographically secured channel K1. The communication is again routed via token 2. In this case, the token functions as an RFID reader for the smartcard 2. Thus, the first cryptographically secured channel K1 between terminal T and smartcard 1 is established via the encrypted connection to the token 2 and via the contactless interface of the token and the smartcard. As described above, corresponding keys A and B are again negotiated via the individual channels K1 or K2, from which then a common key C is generated which can later be used to establish a secure channel K3 between smart card 1 and token 2.

In a fifth embodiment, which is shown in FIG. 4, the second data carrier unit used instead of a USB token is a mobile telephone 2, which in turn has an NFC interface 2b and a corresponding secure element SE, whereby the use of a secure device Elements in combination with an NFC interface well known in the art. The terminal T is again a remote terminal, for example in the form of a so-called trusted center, which can communicate with the mobile telephone 2 via a radio network MN (eg GSM, GPRS, UMTS, WLAN and the like). An end-to-end encryption is provided between the secure element SE and the trusted center 2. The second cryptographically secured channel K2 is established via an intermediate circuit of the radio network between the terminal T and the mobile telephone 2. Communication via the first cryptographically secured channel K1 takes place between the trusted center T and the smartcard 1 by routing via the NFC interface 2b of the mobile telephone 2. The NFC interface functions as an RFID reader. Thus, the first cryptographically secured channel between the terminal T and the smart card 1 with the interposition of the radio network MN and the NFC interface of the mobile phone and the NFC interface of the smart card 1 is established.

In turn, appropriate session keys A and B are derived via the corresponding channels K1 and K2, from which the key C is then calculated, which is provided via the channels K1 or K2 of the smartcard 1 and the mobile telephone 2, which thereupon provide a secure channel K3 using the key C. As already mentioned above, corresponding session keys A and B can be negotiated with methods known in the art. In particular, for example, the smart card 1 may be an electronic identity document, with the construction of the first cryptographically secured channel K1 a corresponding authentication or signature application being executed. Corresponding authentication or signature applications are described in the above-mentioned documents [1] and [2]. In particular, the known from the prior art PACE protocol can be used.

Authentication between the terminal and a respective data carrier unit can also be done manually by a user. For example, the user may enter a self-selected password into the terminal and the volume unit. For this purpose, the terminal T and the data carrier unit may have, for example, a corresponding input option for the password. In this way, a user can ensure that the terminal and volume unit have the same password. Alternatively, the terminal or the data carrier unit can generate a password and the user inputs this password to the other device. Alternatively, the password for the terminal T for the authentication of the first and / or second data carrier unit is routed through an SSL / TLS connection.

Subsequently, the negotiation of the key is done via secure messaging, in particular using the PACE protocol.

To realize various access rights in the subsequent construction of a secure channel using the negotiated key C, a so-called. CHAT can be used, which is an authorization information according to the prior art (eg only read right, no very eib rights assignment and the same). Depending on the desired access rights, a key is then used for establishing a secure channel K3 between the first and second data carrier unit, which is generated by linking the negotiated key C with the CHAT information. In particular, the key C can be hashed with the CHAT. The CHAT thus acts as a key identity to which various rights are linked, and is used as an input parameter in combination with the negotiated key C for establishing the secure channel K3.

According to the preceding embodiments of FIGS. 1 to 4, the first data carrier unit 1 and the second data carrier unit 2 have a common key C, which can be used for subsequent sessions to set up a secure channel. The generation of the common key C can take place in the field between a local terminal T with corresponding contactless or contact-type interfaces (FIG. 1 and FIG. 2), or possibly also in a remote persona tion device, such as a registration office, trust center and the like (Figs. 3 and 4). After the expiry The common key C can then be used to establish a secure channel between the first data carrier unit 1 and the second data carrier unit 2, without any further security mechanisms, such as eg

PACE, needed for authentication. Thus, the communication is extremely performant and yet secure, since only the first data carrier unit 1 communicates with the second data carrier unit 2 on the secure channel.

bibliography

[1] Technical Guideline TR-03110: Advanced Security Mechanisms for Machine Readable Travel Documents, Version 2.02, BSI, 2009.

[2] CEN EN 14890: Application Interface for Smart Cards used as Secure Signature Creation Devices, Part 1 and Part 2.

S e c tio n s

1 first volume unit

2 Second volume unit

2a Contact interface

2b Contactless interface

3 SAM module

A, B, C Cryptographic keys Kl, K2, K3, Kl 'Cryptographically secured channels

T terminal

Claims

Patent claims

1. A method for allocating a first data carrier unit (1) to a second data carrier unit (2), in which:

between the first data carrier unit (1) and a terminal computer (T), a first cryptographically secured channel (K1) is established based on a first cryptographic information (A);

- a second cryptographically secured channel (K2) based on a second cryptographic information (B) is established between the second data carrier unit (2) and the terminal computer (T);

a third cryptographic information (C) based on the first and / or second cryptographic information (A, B) in the terminal computer (T) is determined and from the terminal computer (T) to the first and / or second data carrier unit (1, 2) is transmitted via the first and / or second cryptographically secured channel (K1, K2), so that the third cryptographic information (C) of the first and second data carrier unit (1,

2) is available, wherein the third cryptographic information (C), a third cryptographically secured channel (K3) between the first and second data carrier unit (1, 2) independently of the terminal computer (T) can be constructed.

2. The method according to claim 1, characterized in that the first data carrier unit (1) negotiates with the terminal computer (T) a first cryptographic key (A) over which the first cryptographically secured channel (Kl) is established, and the second data tenträgereinheit (2) with the terminal computer (T) a second kryp- negotiated tographischen key (B) over which the second cryptographically secured channel (K2) is established.

Method according to Claim 2, characterized in that the terminal computer (T) derives from the first and second cryptographic keys (A, B) a third cryptographic key (C) which is transmitted to the first data carrier unit (C 1) via the first cryptographically secured channel (K 1). 1) and via the second cryptographically secured channel (K2) to the second data carrier unit (2) is transmitted.

Method according to one of the preceding claims, characterized in that the terminal computer (T) is a signature terminal for electronic identity documents and secure messaging, in particular based on a password-based transport protocol and particularly preferably based on the PACE protocol, the first and / or second cryptographically secured channel (Kl, K2) between the signature terminal (T) and the first and / or second data carrier unit (1, 2), which are each electronic identity documents, is constructed.

Method according to one of the preceding claims, characterized in that in the method a first and / or second data carrier unit (1, 2) with a contactless and / or contact interface, in particular a chip card and / or a token and / or an electronic identity document and The contactless and / or contact-type interface of the first data carrier unit (1) can be used to construct the first cryptographically secured channel (K1, K2). det, and the contactless and / or contact interface (2a, 2b) of the second data carrier unit (2) is used to construct the second cryptographically secured channel (K2).

Method according to one of the preceding claims, characterized in that in the method a terminal computer (T) with a contactless interface (4) and / or a contact interface (5) is used, wherein the contactless and / or the contact interface (4, 5) are used to construct the first and / or second cryptographically secured channel (K1, K2).

Method according to one of the preceding claims, when dependent on claim 5 and 6, characterized in that the first cryptographically secured channel (Kl) directly between the contactless interface (4) of the terminal computer (T) and the contactless interface of the first data carrier unit (1) is constructed and the second cryptographically secured channel (K2) directly between the contact interface (5) of the terminal computer (T) and the contact-type interface (2a) of the second data carrier unit (2) is constructed.

Method according to one of the preceding claims, when dependent on claims 5 and 6, characterized in that the first cryptographically secured channel (Kl) between the contact interface (5) of the terminal computer (T) and the contactless interface of the first data carrier unit (1) via the contact-type interface (2a) of the second data carrier unit (2) and the contactless interface (2b) of the second data carrier unit (2) are constructed and the second cryptographically secured channel (K2) is constructed directly between the contact-based interface (5) of the terminal computer (T) and the contact-type interface (2a) of the second data carrier unit (2).

Method according to one of the preceding claims, when dependent on claim 5 and 6, characterized in that the first cryptographically secured channel (Kl) directly between the contactless interface (4) of the terminal computer (T) and the contactless interface of the first data carrier unit (1) is constructed and the second cryptographically secured channel (K2) directly between the contactless interface (4) of the terminal computer (T) and the contactless interface (2b) of the second data carrier unit (2) is constructed.

Method according to one of the preceding claims, when dependent on claim 5, characterized in that the terminal computer (T) is a terminal server, which is connected via a secure Internet connection and / or a VPN connection to a computer (6) to which the second data carrier unit (2) via its contact-type interface (2a) is connected, wherein the first cryptographically secured channel (Kl) between the terminal server (T) and the contactless interface of the first data carrier unit (1) via the connected to the terminal server (T) computer (6) and the contact-based and contactless interface (2a, 2b) of the second data carrier unit (2) is constructed and wherein the second cryptographically secured channel (K2) between the terminal server (T) and the contact interface (2a) of the second data carrier gereinheit (2) via the connected to the terminal server (T) computer (6) is established.

11. The method according to any one of the preceding claims, when dependent on claim 5, characterized in that the second data carrier unit (2) is a radio (2), in particular a mobile device, with a contactless interface and the terminal computer (T) is a terminal server, wherein the first cryptographically secured channel (Kl) between the terminal server (T) and the contactless interface of the first data carrier unit (1) with the interposition of a mobile radio connection or a local radio connection using the radio (2) and via the contactless interface (2b) of the radio (2) is constructed and wherein the second cryptographically secured channel (K2) between the terminal server (T) and the radio (2) with the interposition of a mobile radio connection or a local radio connection using the radio (2) is established

12. The method according to any one of the preceding claims, character- ized in that after the construction of the second cryptographically secured channel (K2), an application is transmitted via this channel to the second data carrier unit (2) and installed there, wherein for the execution of the application of third cryptographically secured channel (K3) must be constructed.

13. The method according to claim 12, characterized in that the application for the first data carrier unit (1) over the second cryptographically secured channel (K2) is personalized.

System comprising a terminal (T), a first data carrier unit (1) and a second data carrier unit (2), which is configured such that in operation of the system:

- between the first data carrier unit (1) and a terminal computer (T), a first cryptographically secured channel (Kl) is constructed based on a first cryptographic information (A);

a second cryptographically secured channel (K2) is set up on the basis of a second cryptographic information (B) between the second data carrier unit (2) and the terminal computer (T);

a third cryptographic information (C) based on the first and / or second cryptographic information (A, B) in the terminal computer (T) is determined and from the terminal computer (T) to the first and / or second data carrier unit (1, 2) is transmitted via the first and / or second cryptographically secured channel (K1, K2), so that the third cryptographic information (C) is available to the first and second data carrier units (1, 2), wherein the third cryptographic information item (C) is available. a third cryptographically secured channel (K3) between the first and second data carrier unit (1, 2) can be constructed.

15. System according to claim 14, characterized in that with the system, a method according to any one of claims 2 to 13 is feasible.