Abstract:
A near field communication device ( 100 ) for providing a communication path between a processing unit of the device and an external device, wherein the device ( 100 ) comprises the processing unit ( 102 ) and a control unit ( 101 ) coupled to the processing unit, wherein the control unit ( 101 ) is adapted for establishing a communication between the control unit and the external device ( 104 ) for providing a communication path between the processing unit and the external device via the control unit serving as a gateway.

Description:
FIELD OF THE INVENTION 
     The invention relates to a near field communication device for providing a communication path between a processing unit of the device and an external device. 
     Beyond this, the invention relates to a method of for providing a communication path between a processing unit of the device and an external device. 
     Further, the invention relates to a communication system. 
     Moreover, the invention relates to a program element. 
     Furthermore, the invention relates to a computer-readable medium. 
     BACKGROUND OF THE INVENTION 
     The number of applications used in mobile devices, in particular mobile phones, increases more and more. Thus, the way of communication carried out by mobile phones changes. For example Near Field Communication (NFC) is being adopted by mobile phones for various applications like smart posters, ticketing, payments etc. ETSI (European Telecommunication Standards Institute) for example is specifying a Host Controller Interface and Single Wire Protocol standard for interaction of a UICC (universal integrated circuit card), for example a SIM card, host with a NFC device (NFC chip in the mobile phone). This standard may also be adopted for the interaction of the mobile host (host processor of the mobile terminal) with the NFC device. 
     In such a NFC enabled device typically there are one or more Secure Elements (Secure Storage for storing transaction related information). A SIM (subscriber identity module) Card or UICC is also such a Secure Element and there could be other forms like Secure Element in a removable SDIO (secure digital input output) memory card or a Contact less Secure Element (embedded or integrated with a NFC integrated circuit (IC)). Typically a SIM or SDIO Card Memory has a contact interface to the mobile host processor. This may be used for various operations such as configuration, downloading applications and retrieving status information to the Secure Elements, irrespective of whether the device is NFC enabled or not, governed by protocols like ISO 7816. Commonly mobile phones need to establish a connection between the NFC device and a host as well as between the UICC and the host. 
     OBJECT AND SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an efficient and simple near field communication device for providing a communication path between a processing unit of the near field communication device and an external device. 
     In order to achieve the object defined above, a near field communication device for providing a communication path between a processing unit of the device and an external device, a communication system, a method of providing a communication path between a processing unit of a near field communication device and an external device, a program element and a computer-readable medium according to the independent claims are provided. 
     According to an exemplary embodiment of the invention, a near field communication device is provided for providing a communication path between a processing unit of the device and an external device, the device comprising the processing unit and a control unit coupled to the processing unit, wherein the control unit is adapted for establishing a communication between the control unit and the external device for providing a communication path between the processing unit and the external device via the control unit serving as a gateway. 
     According to another exemplary embodiment of the invention, a method of providing a communication path between a processing unit of a near field communication device and an external device is provided, wherein the method comprises establishing a communication between a control unit of the near field communication device and the external device, and providing a communication path between the processing unit and the external device via the control unit serving as a gateway. 
     According to another exemplary embodiment of the invention, a communication system is provided comprising a near field communication device with the above mentioned features and an external device. 
     According to still another exemplary embodiment of the invention, a program element (for instance a software routine, in source code or in executable code) is provided, which, when being executed by a processor, is adapted to control or carry out a method having the above mentioned features. 
     According to yet another exemplary embodiment of the invention, a computer-readable medium (for instance a CD, a DVD, a USB stick, a floppy disk or a harddisk) is provided, in which a computer program is stored which, when being executed by a processor, is adapted to control or carry out a method having the above mentioned features. 
     Providing a communication path between a processing unit and an external device which may be performed according to embodiments of the invention can be realized by a computer program, that is by software, or by using one or more special electronic optimization circuits, that is in hardware, or in hybrid form, that is by means of software components and hardware components. 
     The term “near field communication” (NFC) may denote a short-range high frequency wireless communication technology which enables the exchange of data between devices over short distances, for example 10 centimeters or around 4 inches. The technology is a simple extension of the ISO/IEC 14443 proximity-card standard (contactless card, RFID) that combines the interface of a smartcard and a reader into a single device. An NFC device may communicate with both existing ISO/IEC 14443 smartcards and readers, as well as with other NFC devices, and is thereby compatible with existing contactless infrastructure already in use for public transportation and payment. NFC and thus this invention may for example be used in mobile phones. 
     The term “processing unit” may denote for example a SIM (subscriber identity module) card, an UICC (universal integrated circuit card) or any other secure element in the communication device. 
     The term “control unit” may denote any kind of unit which is able to provide a gateway for an external device to the processing unit. 
     The communication device may provide a gateway via the control unit so that there is no direct communication path necessary between the external device and the processing unit. In this way, a device may be provided which is secure as there is no direct access to the processing unit which may be any kind of secure element. 
     In the following, further exemplary embodiments of the near field communication device will be explained. However, these embodiments also apply to the communication system, to the method, to the program element and to the computer-readable medium. 
     According to an embodiment of the invention, it may be possible that the control unit is adapted for switching for communicating with a plurality of external devices. Thus, it may be possible for a plurality of external devices to communicate with the processing unit. This communication may be over different communication paths like directly via a contact based interface and associated protocol (ISO 7816) or indirectly via a contact less front end (NFC IC). An NFC IC may act like a bridge between the SIM card or processing unit and a mobile host processor. 
     According to an embodiment of the invention, the control unit is adapted for controlling synchronization of communicating with the plurality of external devices. Thus, the communication may be organized so that there is no interferences between different external devices. 
     According to an embodiment of the invention, the processing unit is a secure element. A secure element may be used to store a digital ID of a user like a payer in such a way that it is very difficult to compromise. A secure element used in the “Secure NFC” technology may enable a versatile range of sensitive applications, such as payment transactions, for mobile devices. A SIM card, a secure flash card, or an embedded security controller may act as a secure element. In this context, all security-relevant transactions and data may be handled by the secure element. Secure NFC may be seen as a secure container integrated into a mobile device. Different applications may be stored in this secure container, operating independent of each other and of the mobile device itself. 
     According to an embodiment of the invention, the processing unit is a universal integrated circuit card or a subscriber identity module card. 
     The term “subscriber identity module” (SIM) card may denote a SIM on a removable SIM card on which a several data may be stored securely, for example a service-subscriber key (IMSI) used to identify a subscriber on mobile technology devices such as computers and mobile phones. 
     The term “universal integrated circuit card” (UICC) may denote a smart card used in mobile terminals in GSM and UMTS networks. The UICC may ensure the integrity and security of all kinds of personal data. 
     According to a further embodiment, the control unit is adapted for using a single wire protocol for establishing the communication to the processing unit. A single wire protocol (SWP) may be a specification for a single-wire connection between the SIM card and a NFC chip in a cell phone. 
     According to an embodiment of the invention, the processing unit is free of a direct communicative coupling with the external device. Thus, the security of such a device may be increased as there exists no further communication path. 
     According to an embodiment of the invention, the device is a mobile device. 
     According to a further embodiment of the invention, the device is realised as at least one of the group consisting of a mobile phone, a hearing aid, a dictating machine, a conference call device, a portable audio player, a portable video player, a head mounted display, a medical communication system, a body-worn device, a DVD player, a CD player, a harddisk-based media player, an internet radio device, a public entertainment device, and an MP3 player. 
     In the following, further exemplary embodiments of the communication system will be explained. However, these embodiments also apply to the near field communication device, to the method, to the program element and to the computer-readable medium. 
     According to an embodiment of the invention, the external device is a mobile host. A mobile host may be any kind of external device or portable terminal which may be connectable to the processing unit via the control unit. 
     The near field communication (NFC) device may be adapted for wireless communication with the external device which may be particularly a reading device, for reading data from the NFC device. For this purpose, the NFC device and the reading device may comprise corresponding transmission elements. For instance, the NFC device may comprise an antenna, wherein the reading device may comprise a corresponding receiving antenna. However, the inventive device is not limited to wireless or contactless data transmission, but in principle also applies to wireless communication. 
     The aspects defined above and further aspects of the invention are apparent from the examples of embodiment to be described hereinafter and are explained with reference to these examples of embodiment. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described in more detail hereinafter with reference to examples of embodiment but to which the invention is not limited. 
         FIG. 1  illustrates a near field communication device according to an exemplary embodiment of the invention. 
         FIG. 2  illustrates a near field communication device and system according to another exemplary embodiment of the invention. 
         FIG. 3  illustrates a simplified system overview of a conventional communication system. 
         FIG. 4  illustrates a communication of an interface between a processing unit (UICC) and a control unit (NFC device. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The illustration in the drawing is a schematic illustration. In different drawings, similar or identical elements are provided with the same reference signs. 
     A typical NFC enabled device like a mobile phone has a Secure Storage Element mostly in the form the SIM card (UICC). In the following, an alternate and uniform method to access such a secure element from the mobile host processor using the NFC IC (Contact Less Front-End: CLF) is described. 
     In a common NFC enabled device typically there are one or more Secure Elements (Secure Storage for storing transaction related information). A SIM Card (UICC) is also such a Secure Element and there could be other forms like Secure Element in a removable SDIO memory card or a Contact less Secure Element. Typically a SIM or SDIO Card Memory has a contact interface to the mobile host processor. This is used for various operations such as configuration, downloading applications and retrieving status information to the Secure Elements governed by protocols like ISO 7816. 
     A typical system is described in  FIG. 3 . In case of a NFC enabled device  300 , the NFC IC  301  provides a Contact-less Front end for these Secure Elements  302 ,  303  to be visible to external RF readers or read contactless cards comprising an antenna  305  over RF, thus making these secure elements contact-less secure elements. The interface between the SIM Card and the NFC IC is defined by the ETSI SWP and ETSI HCI standard. The mobile host processor  304  is also connected over another interface to the NFC IC. This link is typically used to configure the NFC IC and getting status information. One set of such status information (transaction ID, transaction start, end etc.) passed to the mobile host processor contains what transactions occurring between external reader and the SIM Card. 
       FIG. 4  illustrates an NFC Host Controller Interface. ETSI defines the interface between the UICC (SIM) or Smart Card and Contact-less Front-end (NFC device) as in technical specification ETSI TS 102 613 V7.4.0 (2008-12)-SWP and ETSI TS 102 622 V7.3.0 (2008-12)-HCI. The basic concept of the NFC HCI is standardized Command-Response and Event exchange mechanism between a Host and Host Controller as shown in  FIG. 4 . The command exchange occurs between gates that represent a specific feature/module using a logical connection called Pipes. 
     The ETSI HCI specification details the specific gates, pipes, commands, responses and events for Smart Card/UICC to CLF Interface. The mechanisms usable in this invention are similar to mechanisms used by NFC IC to expose the SmartMX secure element connected to the NFC IC over the S2C interface (also called NFC-WI or NFC-Wired Interface) to the mobile host processor. The NFC-WI is basically for exposing the secure element to the external RF reader, but is also used for making the secure element accessible to the Host Processor by the NFC IC. 
     As shown in  FIG. 3 , the SIM card  302  and similar Secure Storage elements  303  are connected to the mobile host processor  304  over two interfaces. Directly via the contact based interface (direct link between mobile host processor and UICC) and associated protocol (ISO 7816) and indirectly via the contact less front end (NFC IC). NFC IC  301  acts like a bridge between the SIM card and mobile host processor. 
     In a typical NFC application, the SIM card used as a secure storage needs to be managed using the ISO 7816 commands for example downloading application, setting privileges and enabling/disabling application that are visible from external RF reader, knowing which application was accessed from the external reader etc. The multiple interfaces mentioned leads to applications, needing to access the SIM card over two different interfaces for functions related to secure storage. All ISO 7816 based communication needs to be via the contact interface. Information regarding access by external RF reader is only available over the NFC-IC mobile host processor interface. 
     This may further be complicated by the fact that the application using the NFC-IC and applications using the ISO 7816 contact link may be different software entities which need synchronization mechanism when interdependent sequences have to be performed. This is also essential to avoid simultaneous access of the SIM Card between these two interfaces as well when being access over the NFC IC via the external RF Reader. This can lead to conflict in transaction or failure of transaction being done by external reader. 
     To overcome the problem caused by the multiple interfaces a near field communication device is provided in which the NFC IC provide a mechanism to send ISO 7816 commands to the SIM Card. This is shown in  FIG. 1 . When all communication to the SIM  102  is via the NFC IC  101  then it can implement policy for prioritization of access to avoid any synchronization or conflict or failure of transaction issue, for example making some access mutually exclusive. 
     This solution utilizes the fact that the NFC IC is connected to the SIM over the SWP interface, to the mobile host processor  104  over another interface and to the external RF Reader over RF. Secondly, the external RF Reader in typical cases interacts with the SIM (secure storage of the SIM) using the ISO 7816 protocol after the SIM has been activated by NFC protocol interaction between the RF Reader and the NFC IC. Thirdly, the NFC IC can also behave like a Card Reader on behalf of the host processor. 
     In this case, the NFC IC detects external contact less cards in the field, activates them and informs the mobile host processor about the activation. After this point the mobile host processor can transact with the external card using protocols like the ISO 7816, depending on the type of card present. 
     So the NFC IC or control unit can combine these three features of activation of SIM for a reader, channel for ISO 7816 exchange between mobile host processor, NFC IC and SIM to emulate an external RF reader towards the SIM card (on behalf of the mobile host processor) and can provide the mobile host processor a channel for sending ISO 7816 commands to the SIM Card. Thus all NFC related communication towards the SIM card can be done using a single interface via the NFC IC. 
     An NFC IC or control unit  101  as used here may comprise an antenna, an RF reader gate and an RF technology processor. It may communicate with additional secure elements  103  via NFC-WI or some other interfaces and with the UICC  102  via SWP. 
     The processing unit or NFC IC provides a mechanism for the mobile host to configure the NFC IC in Reader Emulation mode towards the SIM Card as shown in  FIG. 2 . The host processor  204  issues this command whenever it needs to access the SIM  202  for ISO 7816 command exchange. When this mode is activated the NFC IC  201  will enable that the SIM card  202  or other optional secure elements  203  gets discovered in its Reader Mode in the same way as an external card would get detected and activated. 
     The NFC IC selects and activates the SIM Card as if there is an external reader. The NFC IC informs the mobile host processor of activation of the card to the mobile host processor as if it is an external card. After this point, the mobile host can transact with the SIM card as if it is an external card using protocols like ISO 7816. 
     The access to the SIM between the mobile host processor and the external RF reader  205  can be easily made mutually exclusive since these are two different modes of the NFC IC. When the NFC IC exposes the SIM to the external RF Reader it may be in a so called ‘Card Emulation’ mode. When the NFC IC exposes the SIM to the mobile host processor it may be in a so called ‘Card Reader Mode’. 
     The communication system  200  provides a single interface for NFC applications to access the SIM using the NFC IC. A single access interface is also advantageous when there are multiple secure elements in the system, ex. Dual SIM Card or a SDIO based secure storage connected to the NFC IC over SWP and over a contact interface to the mobile host processor. 
     The system inherently avoids any conflict and synchronization issues of access between the access to the SIM via Contact interface and via NFC IC. It avoids conflict and synchronization issues of access of the SIM by an external RF Reader and mobile host processor. 
     Further, it possibly reduces the need of pins on the contact interface of the SIM for supporting ISO 7816 interaction. These pins can be utilized for some other function. The system does not require any change in the SIM implementation as the mode is transparent to the SIM Card and does not require new mechanism on the mobile host processor side as it already implements methods to access external cards. 
     It should be noted that the term “comprising” does not exclude other elements or features and the “a” or “an” does not exclude a plurality. Also elements described in association with different embodiments may be combined. 
     It should also be noted that reference signs in the claims shall not be construed as limiting the scope of the claims.