WO2008046723A1

WO2008046723A1 - Rfid chip

Info

Publication number: WO2008046723A1
Application number: PCT/EP2007/060207
Authority: WO
Inventors: Peter Hagl; Markus Moser; Martin Pelzmann; Alfred Pohl
Original assignee: Siemens Aktiengesellschaft
Priority date: 2006-10-19
Filing date: 2007-09-26
Publication date: 2008-04-24
Also published as: DE102006049376A1

Abstract

The invention relates to an RFID chip (1) comprising a transmitting and receiving unit (2) for transmitting and receiving radio signals (3), a memory (4) for storing and reading at least a transaction number (TAN) and a comparator unit (5) for activating at least one RFID process step based on a comparison of a TAN stored in the memory with a TAN received via the transmitting and receiving unit (2).

Description

description

RFID chip

The invention relates to an RFID chip with a transmitting / receiving unit for transmitting and receiving radio signals, an RFID read / write device and a method for operating an RFID chip.

Automated readable radio tags, so-called RFIDs ("Radio Frequency Identification"), are important elements of automatic recognition of goods and environmental parameters and elements. RFIDs are typically simply constructed radio tags that emit the information stored on them in response to a suitable radio query (so-called "ping"). However, due to their simple design, they are vulnerable to unauthorized attacks and require special protection if sensitive information is stored. Possible attacks can be As so-called DoS ("denial-of-service") attacks, virus attack, data manipulation or even a simple unauthorized reading. If no effective protection is incorporated into the RFIDs, these are not applicable, above all, in security-relevant areas or in the private sector. To protect the transmitted data from being read by unauthorized third parties, RFIDs have been proposed that include an encryption unit for encrypting the data they send. However, this increases the complexity and thus the costs of the RFIDs, which would considerably impair their acceptance as simple radio tags which can be used everywhere.

It is therefore the object of the invention to provide a possibility for increasing the security of RFIDs against unauthorized access while at the same time not significantly increasing the complexity of the RFIDs. This object is achieved by an RFID chip according to claim 1, a set of RFID chips according to claim 11, an RFID read / write device according to claim 12 and a method according to claim 15. Preferred embodiments are in particular the dependent claims alone or in combination removed.

For this purpose, TAN methods, which are known, for example, for bank transfers, are now applied to the field of RFIDs. In general, all known TAN methods and technologies can be used. In this case, TAN stands for "transaction number", an enabling clearing or enabling of RFID progress steps. Authorization code, which in the context of this invention, all suitable alphanumeric data are understood, so for example, a combination of letters, special characters and / or numbers. RFID process steps are carried out in RFID in order to achieve certain actions. Possible actions are sending out passwords and / or passwords, writing passwords, etc. The invention is not limited to certain fields of application or actions of RFID chips.

Thus, the object is achieved by an RFID chip having a transmitting / receiving unit for transmitting and receiving Funkksig- signals, which has a memory for storing and reading at least one transaction number, TAN, and a comparison unit for releasing at least one RFID A step of executing on the basis of a comparison of a TAN stored in the memory with a TAN received via the transmitting / receiving unit. Preferably, initially several TANs ("TAN list") are stored in memory. The comparison unit can thus fulfill the function of an authorization unit.

Firstly, the use of TANs greatly increases data security since only the one in possession of a valid TAN gets access to the RFID chip. Secondly The RFID chip only needs to have simple memory and a simple comparison unit instead of an encryption circuit.

If, in a typical application, a TAN is transmitted to the RFID chip - usually from a read / write device for writing and / or reading RFIDs - the comparison unit will compare the received TAN with a stored TAN. If the TANs agree (which generally need not mean identity of the TANs, but may mean meeting a predetermined relationship to each other, eg, a mathematical relationship), the RFID chip will switch at least one RFID expiration step associated with the received TAN , possibly a sequence of steps, free, so that it is performed by the RFID.

This can typically be done so that an instruction sequence is received by the RFID chip comprising at least the TAN and at least one action. If the TAN is valid, the at least one action, which may include one or more RFID expiration steps, is performed. The action may be transmitted, for example, in the form of a command code and a data field. Command codes may, for example, cause the transmission of an RFID tag, storage of a password or other data, transmission of a stored password or other stored data, and so on.

Preferably, at least one TAN stored in the RFID chip is provided with an expiration date. If, for example, a date field is transmitted by the RFID chip with the instruction sequence, the comparison unit can also compare the date in addition to the actual TAN identifier and make an activation dependent on whether the transmitted date lies within an allowed range. This is particularly advantageous if the activation of a transmission of a date field is mandatory, since such an unauthorized handling of the RFID chip is further complicated, especially if one Date setting in the proposed RFID read / write device by the end user is no longer possible.

An unauthorized handling of the RFID chip is alternatively or additionally made more difficult in such a way that at least one stored in the memory TAN is preferably provided with a location identifier, the z. B. is automatically generated and transmitted by a designated RFID read / write device via a GPS receiver.

Similarly, at least one TAN stored in memory may preferably be provided with a time tag which is compared to a content of a received time field. If the received time window is outside the time window assigned to the TAN in the RFID, no activation takes place. In this case, a time setting in the provided RFID read / write device by the end user is preferably no longer possible.

In particular, in order to prevent handling of the RFID chip by an unintentional RFID read / write device, the at least one TAN stored in the memory is preferably provided with an RFID read / write device identifier, which in addition to the transmission of a correct TAN for Activation is needed.

Preferably, the activation for a predetermined time, e.g. Seconds, and / or a predetermined number of process steps or actions valid (analogous to the so-called "sion TAN"). Thereafter, the transmission of another sion TAN is necessary.

It can be favorable if the RFID chip has a means for deleting a TAN after a successful activation by comparison with this TAN. This restricts the number of maximum possible, even unauthorized, actions. This is especially important for writing data on the RFID. One possible application scenario is the writing or overwriting of data on the RFID chip, for example an RFID identifier or a password, by a writer authorized to write, and TAN-less, ie, as often as possible, readout of the identifier by an associated one Read / write device.

It can also be advantageous if the RFID chip has a means for blocking and / or deleting all TANs after a predetermined number of failed comparisons, since this further prevents a malicious RFID query. As a result, the RFID chip is at least initially inoperable for such sequence steps which require TANs.

It is advantageous if at least one TAN is assigned an activation of at least one predetermined RFID process step. In other words, certain TANs can be assigned certain unlocked process steps, while other TANs are assigned different types or sequences of process steps. This ensures that even if a TAN is cracked, this does not necessarily allow all possible procedural steps. It may also be possible to sequence steps that are allowed without TANs, z. B. a transmission of an RFID identifier.

It is particularly advantageous if the RFID chip has an iTAN request circuit for transmitting a request radio signal after a TAN after receiving a command radio signal. Typically, such an RFID chip will be used in the so-called iTAN method, which is encompassed by the present invention as a special type of TAN method. In this case, a specific TAN (eg: "TAN No. 5") is requested by the RFID chip, typically after receipt of an instruction sequence or an instruction announcement sequence, from the RFID read / write device which has a TAN stored in the RFID chip is to be compared. iTANs have the advantage of avoiding that when If parts of a TAN list become known, all RFIDs populated with this TAN list will automatically be considered hacked. Depending on the size of the list and the degree of compromise, a satisfactory level of security may still be present, particularly using one or more of the above-mentioned other enabling conditions, such as time, date, location, reader recognition, and so forth.

In one embodiment, all possible TANs (TAN, iTAN, etc.) are stored in the RFID read / write device so that it autonomously selects and selects a correct TAN (in the simple TAN method) or the requested TAN (in the iTAN method) can transmit the RFID chip.

A higher security against manipulation is achieved by means of the use of a challenge-response method, for. B. in that a TAN (TAN, iTAN, etc.) must be requested by the RFID read / write device from an external TAN database. For this purpose, preferably a secure connection is established to a computer unit which has access to the external TAN database. Conveniently, the RFID read / write device must authenticate to the computer unit, for. B. by sending an identifier of the read / write device. In addition, an RFID tag, an envisaged transaction and / or other data may be transmitted to the

Selection of a valid TAN will be needed. The use of a centrally managed database, eg. In a trust center, can most effectively prevent uncontrolled trial and denial of service (DoS) attacks. In particular, this makes it possible to use an RFID chip as an "RFID trasor" in which data is stored securely in the RFID chip. Only by the correct TAN - if necessary with the other side conditions mentioned above, such as time, date, place, reader recognition etc. - data can be manipulated, ie read and / or write. Preferably, in the case of a set of multiple RFID chips, the memory of all RFIDs may initially be filled with the same TANs.

The TANs can either be initially filled by the manufacturer and then provided to a customer or the database, or the TANs can be initially filled by the customer. The setting in the database allows the highest data security.

In the following embodiment, an aspect of the invention is schematically illustrated in more detail.

1 shows a sketch of a system for using an RFID chip equipped with a TAN list.

1 shows an RFID chip 1 with a transmitter / receiver unit 2 for transmitting and receiving radio signals 3. The RFID chip 1 also has a memory 4 for storing and reading at least one transaction number, a so-called TAN, as indicated by the dashed arrow. Furthermore, it has a comparison unit 5 for activating at least one RFID process step on the basis of a comparison of a TAN stored in the memory with a TAN received via the transmitting / receiving unit 2.

The RFID chip 1 can be described and read by means of an RFID read / write device 6 by radio signals 3.

The RFID read / write device 6 has a means for transmitting a TAN to the RFID chip 1 (not shown).

The TANs stored in the memory 4 are all provided with an expiration date and, with a location identifier, a time identifier and an RFID reader / writer identifier. This represents a high level of security since the RFID chip 1 can only nipulated (read and / or described) can be when a TAN transmitted by the RFID read / write device 6 by an instruction sequence with a TAN stored in the memory 4 matches and also the instruction sequence at the right time (date and time), in the right place and is transmitted to the RFID chip 1 with the predetermined reader.

The instruction sequence may, for example, have a form comprising a header, a command or instruction section with instructions for the RFID chip 1, a TAN section with the TAN, a date section, a location section Information about the correct location area (eg in longitudes and latitudes), a time segment, an ID of the RFID

Read / write device 6 and optionally other sections, such as blocks of data with a password to be written.

From the read / write device 6 can be transmitted, depending on the configuration of the RFID chip 1, individual TANs to perform an action, iTANs, session TANs or a combination thereof.

In the embodiment shown here, the TAN used for a successful activation is deleted, but it does not need to be, for example, when using a TAN.

The RFID chip 1 has, not shown, means for

Locking and / or deleting all TANs after a predetermined number of failed comparisons, which in particular prevents DoS attacks and unauthorized systematic queries.

In this embodiment, the RFID chip 1 has initially been filled with TANs, of which various groups have been used. allow different RFID processes, and some TANs allow full access to all RFID process steps.

The RFID read / write device 6 does not hold a TAN list, but instead has to manipulate the RFID chip 1 to retrieve a valid TAN via a secure connection 7 from a central server 8, which has access to the corresponding TAN. Here, the structure of the central server 8, the external computer unit, irrelevant and may for example consist of a central computer, a computer cluster or a computer network. The TAN database can be stored centrally or remotely.

To obtain a TAN by the central server 8, the RFID read / write device 6 sends a corresponding request to the central server 8, the at least one identifier of the RFID chip 1, an intended action of the RFID chip 1 and an identifier of the write / Reader 6 to the external computer unit includes.

After authentication of the read / write device 6 via its identifier, the central server 8 sends back a TAN valid for the specific RFID chip 1 and for the specific action to the RFID read / write device 6. This TAN is then transmitted in a suitable instruction sequence to the RFID chip 1 which, after successful comparison of this TAN with the list of stored TANs and the other boundary conditions, enables the associated action or actions.

When using the iTAN method, the RFID chip, which has an iTAN request circuit 9 for this purpose, requests a specific TAN (eg, "TAN No.") by transmitting a request radio signal after receiving a command radio signal from the RFID read / write device 6. For example, the requested iTAN may depend on the future action indicated, for example, in the command radio signal: In the high security solution illustrated here, the RFID read / write device 6 will suffice this request, together with an identification of the RFID read / write device 6 for authentication, to the central server 8, which returns the specific requested (i) TAN to the RFID read / write device 6, which sends it to the RFID Chip 1 forwards. This performs the already transmitted with the command radio signal action or transmitted actions.

Of course, the invention is not limited to the more specifically illustrated embodiments, but may include the application of all known TAN methods, including TAN, iTAN, Session TAN, etc., including all alternatives available to those skilled in the art after reading the disclosure set forth herein.

LIST OF REFERENCE NUMBERS

1 RFID chip

2 transmitting / receiving unit 3 radio signal

4 memories

5 comparison unit

6 RFID read / write device

7 connection 8 central server

9 iTAN request circuit

Claims

claims

An RFID chip (1) comprising a transceiver unit (2) for transmitting and receiving radio signals (3), characterized by further comprising:

- a memory (4) for storing and reading at least one transaction number, TAN;

- A comparison unit (5) for activating at least one RFID expiration step based on a comparison of a TAN stored in the memory with a via the transmitting / receiving unit (2) received TAN.

2. RFID chip (1) according to claim 1, characterized in that at least one TAN stored in the memory is provided with an expiration date.

3. RFID chip (1) according to claim 1 or 2, characterized in that at least one stored in the memory TAN is provided with a location identifier.

4. RFID chip (1) according to one of claims 1 to 3, characterized in that at least one in the memory

(4) stored TAN is provided with a time identifier.

5. RFID chip (1) according to one of claims 1 to 4, characterized in that at least one in the memory (4) stored TAN is provided with an identifier of the RFID read / write device (6).

6. RFID chip (1) according to one of claims 1 to 5, characterized in that the activation for a predetermined time and / or a predetermined number of processing steps is valid.

7. RFID chip (1) according to one of claims 1 to 6, characterized in that it comprises means for canceling a TAN after a successful activation by comparison with this TAN.

8. RFID chip (1) according to one of claims 1 to 7, characterized in that it comprises a means for blocking and / or deleting all TANs after a predetermined number of failed comparisons.

9. RFID chip (1) according to one of claims 1 to 8, characterized in that the at least one TAN an activation of at least one predetermined RFID expiry step is assigned.

10. RFID chip (1) according to one of claims 1 to 9, characterized in that the RFID chip (1) has an iTAN request circuit (9) for transmitting a request radio signal to a TAN after receiving a command radio signal.

11. Set of a plurality of RFID chips (1) according to one of the preceding claims, characterized in that the respective memory (4) of all RFIDs is initially filled with the same TANs.

12. RFID read / write device (6) for writing data in the RFID and / or for reading data from the RFID, characterized in that it comprises a means for transmitting a TAN to the RFID.

13. RFID read / write device (6) according to claim 12, characterized in that it comprises means for requesting a TAN from an external computer unit (8) having access to a TAN database.

14. RFID read / write device according to claim 13, characterized in that it comprises a means for transmitting at least one RFID identifier, a designated transaction and / or an identifier of the read / write device to the external computer unit.

15. A method for operating an RFID chip, in particular an RFID chip according to one of claims 1 to 10, characterized in that it comprises the following steps: - Transferring a TAN from an RFID read / write device to an RFID chip (1) ;

Comparing, in the RFID chip (1), the TAN received by the RFID read / write device (6) with a TAN stored in the RFID; and - enabling, in the RFID chip (1), at least one RFID execution step upon successful comparison of the received TAN with a stored TAN.

16. The method according to claim 15, characterized in that it further comprises the following preceding step:

Request, by the RFID read / write device (6), a TAN for transmission to the RFID chip (1) from an external computer unit (8), in particular after transmission, to the external computer unit, at least one RFID identifier, a designated transaction and / or an identifier of the read / write device (6).

17. The method according to claim 15 or 16, in particular an RFID chip (1) according to claim 10, characterized in that it further comprises the following preceding step:

Request, through the RFID chip (1), a specific

TAN from the RFID read / write device (6).