Abstract:
A method for data transmission between a sensor module for measuring and storing data and a mobile device wherein the sensor module and the mobile device have identified each other and, wherein the sensor module comprises a first secure element capable of storing a first security key and the mobile device comprises a second secure element capable of storing a second security key characterized in that the method comprises the steps of an authentication step for carrying out a security process between the sensor module and the mobile device in order to authenticate the sensor module with the mobile device by means of comparing first and second security keys; a pairing step for establishing a communication between the sensor module and the mobile device in order to enable communication therebetween; a transmission step for establishing a secure transmission of data from the sensor module to the mobile device when comparison of the first and second security keys has resulted in authentication.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention relates to a method and system for improving the data transmission of a sensor such as a sensor used in a medical domain. 
       BACKGROUND OF THE INVENTION 
       [0002]    The use of bio-sensor (i.e. biological sensor) systems is widespread in the medical domain Bio-sensor systems provide remote patient monitoring in order to prevent, control and reduce chronic diseases such as diabetes, for example. Such systems comprise a bio-sensor located on the body of a patient and also connected to an information system. The bio-sensor detects specific data related to the disease of the patient such as the level of a component in the blood of the patient, for example. The bio-sensor then transmits the data to the information system. Thus, the information system can store and analyze the transmitted data in order to provide a diagnosis or a suggested treatment for the patient. Depending on the content of the information, the bio-sensor can effectively provide an alert if the analysis provides a critical result for the health of the patient. However, current day bio-sensors are typically bulky and as such inconvenient for the patient. Also, bio-sensors transmit data, which is not secured in any manner. This means that the data can easily be intercepted, which is unacceptable in terms of the confidentiality of personal health records. 
       SUMMARY OF THE INVENTION 
       [0003]    An object of the present invention is to alleviate some of the problems associated with the prior art systems. 
         [0004]    More particularly, a further object of the invention is to provide a method and system for providing a secure transmission of information between a sensor and an information system. 
         [0005]    According to one aspect of the present invention, there is provided a method for data transmission between a sensor module for measuring and storing data and a mobile device wherein the sensor module and the mobile device have identified each other and, wherein the sensor module comprises a first secure element capable of storing a first security key and the mobile device comprises a second secure element capable of storing a second security key, characterized in that the method comprises the steps of an authentication step for carrying out a security process between the sensor module and the mobile device in order to authenticate the sensor module with the mobile device by means of comparing first and second security keys; a pairing step for establishing a communication between the sensor module and the mobile device in order to enable communication therebetween; a transmission step for establishing a secure transmission of data from the sensor module to the mobile device authentication when comparison of the first and second security keys has resulted in authentication. 
         [0006]    According to a second aspect of the present invention there is provided a system for data transmission between a sensor module for measuring and storing data and a mobile device wherein the sensor module and mobile device have identified each other, and wherein the sensor module comprises a first secure element capable of storing a first security key and the mobile device comprises a second secure element capable of storing a second security key characterized in that the system comprises the steps of an authentication module for carrying out a security process between the sensor module and the mobile device in order to authenticate the sensor module with the mobile device by means of comparing first and second security keys; a communication module for establishing a communication between the sensor module and the mobile device in order to enable communication therebetween; a transmission module for establishing a secure transmission of data from the sensor module to the mobile device when comparison of the first and second security keys has resulted in authentication. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    Reference will now be made, by way of example, to the accompanying drawings, in which: 
           [0008]      FIG. 1  shows a user wearing a sensor device in accordance with one embodiment of the present invention, by way of example; 
           [0009]      FIG. 2  is a representation of the system in accordance with one embodiment of the present invention, by way of example; 
           [0010]      FIG. 3  shows details of a secure element of the sensor as shown in  FIG. 2 ; 
           [0011]      FIG. 4  is a flow chart of the method steps in accordance with one embodiment of the present invention, by way of example. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0012]    In the following description, the use of the word sensor means any kind of sensor including bio-sensor (i.e. biological sensor). 
         [0013]      FIG. 1  shows a user  100  wearing two sensor devices  200 . As a first example, a first sensor device is located on the chest of the user. As a second example, a second sensor device is located on the wrist of the user. These locations of the sensor device  200  are only examples. 
         [0014]    The user  100  is also in possession of a mobile device  300 . The mobile device  300  can be a mobile phone, a personal digital assistant or any other devices which could effect a wireless communication with another device or which could also make wireless connection to a communications network. The type of communication between the two devices may be a short range communication, for example. 
         [0015]    As shown in  FIG. 2 , the sensor device  200  comprises a specific sensor packaged module  202 . The sensor module  202  comprises several components such as a sensor  204 , a wireless connectivity module  206  and a tag  208 . The sensor  204  can be a bio-sensor (i.e. biological sensor) in order to measure specific data like health parameters of the user such as the blood pressure or a specific blood component for example. The content of data depends on the condition (medical or otherwise) of the user and/or the location of the bio-sensor. 
         [0016]    The sensor  204  connects to a wireless connectivity module  206 . The connection between the sensor  204  and the module  206  can be a Bluetooth™ connection, a ZigBee™ connection, an ultra-wide band connection or any other appropriate means. The module  206  is a communication module typically having an ultra-low power requirement. The module  206  may connect to another wireless connectivity module located in another device such as the mobile device  300 . Thus, the module  206  allows wireless connection of the sensor  204  with another device. 
         [0017]    The wireless connectivity module  206  also connects to a tag  208 . The tag  208  is a Near Field Communication (NFC) contactless tag. The tag  208  is a passive label, which comprises specific data. In the present invention, data relates to the sensor device  102  and also to the health parameters measured on the user  100  with the sensor  204 . The data stored in the tag  208  can be read using a NFC module through Radio Frequency Identification (RFID) in combination with a corresponding NFC contactless tag reader. The tag reader belongs to another device such as the mobile device  300 . The tag  208  includes a secure element (SE)  210  and a non-volatile memory (NVM)  212 . 
         [0018]    The secure element (SE)  210  comprises data which relates to the sensor (or the user or any data associated therewith). As shown in  FIG. 3 , the secure element  210  comprises several components such as for example, a cryptographic processor engine, a secure debug module, a secure Direct Memory Access (DMA) and/or a non-volatile memory for securely storing a secret or private cryptographic key. Including the private key within the sensor has a number of advantages which will become apparent below 
         [0019]    The NVM  212  comprises stored data, which refers to the user sensor or any associated data. The NVM  212  stores data such as health parameters measured for the user through the sensor  204 . The sensor  204  measures such data while the user is wearing the sensor device  200 , which includes the sensor module  202 . The amount of stored data depends on the capacity of the NVM  212 . The refresh process of the NVM  212  is based on a first in first out (FIFO) mechanism where the new stored data replaces the old stored data during a measurement process. 
         [0020]    The sensor also comprises a battery (not shown). The sensor is powered on at the first use when activated. The lifetime of the sensor depends on the lifetime of the battery and the battery could be recharged or replaced. The sensor module  202  can also be replaced if needed. During the manufacturing process of the sensor module  202 , the sensor module  202  is loaded with a unique private device secret key. The sensor private key is stored in the NVM of the SE  210  of the sensor module  202 . The private key allows a unique identification of the sensor module  202 . 
         [0021]    As also shown in  FIG. 2 , the mobile device  300  comprises different components such as a modem device  302 , an application processor  304 , a wireless connectivity module  306 , a NFC reader  308 , a Subscriber Identity Module (SIM)  310  and a local client application  312 . 
         [0022]    The mobile device  300  comprises a communication modem  302  such as a 3G modem for example. The modem  302  may connect to an application processor  304  or be integrated therewith. The modem  302  connects to both a wireless connectivity module  306  and a NFC reader  308  either via the processor  304  or directly. The modem device  302  also connects to a Subscriber Identity Module (SIM)  310 . The SIM module may comprise a further Secure Element (SE)  311  as described in  FIG. 3 . The SIM module  310  connects the NFC reader  308  through a protocol such as a Single Wire Protocol (SWP) and may be used for connectivity purposes. 
         [0023]    The NFC reader  308  also comprises a Secure Element (SE)  309  similar to that described in  FIG. 2 . The SE  309  participates in the security process in order to identify the sensor module  202 . The SE  309  may include a public key which is capable of recognizing a required private key in order to effect an authentication between sensor and mobile device. This will be explained in greater detail below. 
         [0024]    The SE  309  can also be located on a removable card. The removable card can connect the mobile device  300  through for example a specific slot on the mobile device  300  or a specific interface application. The SE  309  can also be used in conjunction with specific International Mobile Subscriber Identity (IMSI) code or International Mobile Equipment Identity (IMEI) code to enable transfer of parameters and profiles. The NFC reader  305  may also include a NVM (not shown), which has a similar function to that of the sensor NVM  212 . 
         [0025]    IMSI is a unique 15-digit code used to identify an individual user on a GSM network. IMEI (International Mobile Equipment Identity) identifies a mobile phone being used on a GSM network. The IMEI is a useful tool to stop a stolen phone from accessing a network and being used. Mobile phone owners that have their phones stolen can contact their mobile network provider and ask them to ban or shut off a phone using its IMEI number. 
         [0026]    The mobile device  300  also comprises a local client application  312 . The local client application can communicate with an information system  400  as described in  FIG. 2  in any appropriate manner. The information system  400  comprises several databases related to different users. The client application  312  can then send data to the information system through wireless communication. 
         [0027]    In the example when the sensor device  200  runs an initialization step (not shown) when the user activates the power of the sensor device located on the user, the sensor  204  of the sensor module  202  then measures user health parameters. Such health parameters may be stored in the NVM  212  of the sensor module  202  until such time as a connection is made to the mobile device. 
         [0028]      FIG. 4  shows the main steps of the process of the present invention. At the beginning of the process, the user must bring the sensor module  202  and the mobile device  300  into close proximity. Such proximity provides a communication between the NFC tag  208  of the sensor module  202  and the NFC reader  308  of the mobile device  300 . This communication launches an identification process of the sensor module  202  as indicated in step  500 . Thus, the sensor module  202  identifies itself to the mobile device. Once this has been carried out it is merely necessary to switch on the sensor and the mobile device in order for one to identify the other. At the end of step  500 , the mobile device  300 , the sensor module  202  is identified as being a matching sensor module for the mobile device  300 . 
         [0029]    The process then continues with the next step  502 , which provides an authentication step in order to check that the identity of the sensor module  202  is not a fake or redundant. The authentication process uses a dual key handling secure process with a private and public key encryption through the well-known RSA encryption algorithm with digital signatures and certificates. The authentication process can occur between the sensor module  202  and the mobile device  300 . The process may use the sensor private key stored in the SE  209  of the sensor module  202  and the public key stored in the SE  309  of the NFC tag reader  308  to enable authentication. The public key in the SE  309  is used to recognize and authenticate the private key of sensor  202  by means of the certificates. At the end of the mutual authentication process, if there is a matching between the private stored key in the NEC tag  209  of the sensor module  202  and the public stored key in the NFC tag reader  308 , the sensor module  202  is fully authenticated as being the sensor module  202  compatible with the mobile device  300 . Thereafter any communication between the sensor  202  and mobile device  300 , in accordance with the private and public keys, will be encrypted so all data will only be readable by the sensor  202  and device  300 . 
         [0030]    The process proceeds with the next step  504 , which deals with a “pairing step”. The pairing process automatically begins as soon as the authentication process is ended with the positive authentication of the sensor module  202  as described above. In fact, the pairing process could be part of the authentication process. The pairing process comprises the activation of both the connection module  206  of the sensor module  202  and the connection module  306  of the mobile device  300 . Thus, both connection modules  206  and  306  can exchange data such as parameters and profiles for establishing a connection between the sensor module  202  and the mobile device  300 . At the end of the pairing process, the sensor module  202  and the mobile device  300  are connected one with the other. The pairing process can occur between the sensor module and the mobile device in combination with the specific IMEI and IMSI codes as indicated above. These are just examples of parameters and profiles for pairing and there may be many others. 
         [0031]    The process proceeds with the next step  506 , which deals with the transmission of the data concerning the user health parameters stored in the NVM  212  of the sensor module  202 . As the identification step  500 , the authentication step  502  and the pairing step  504  have been completed successfully, the transmission of stored data can occur as indicated in step  506 . The stored data are encrypted using the private key stored in the SE  210  of the sensor module  202 . Then, the data are sent in the NVM located in the SE  309  of the mobile device  300  where it can be decrypted. The data is sent with appropriate security parameters in order to ensure the integrity and confidentiality of the transmitted data. The integrity is achieved by using and comparing Hash signatures in the data sent to the mobile device  300  and in the data received in the NVM of the SE  308  of the mobile device. If the comparison results in a positive comparison, it means that the data was not corrupted while being sent from the sensor module  202  to the mobile device  300 . The confidentiality is achieved by using a cipher encryption for encrypting the stored data before their transmission. 
         [0032]    If the transmission is interrupted for any reason the data that was not totally transferred will be resent to the NVM ( not shown) of the mobile device at the next initialization step of the sensor module  202  based on the data stored in the NVM  212 . 
         [0033]    At the end of the transmission step  506 , the mobile device  300  can send all the transmitted data to an information system  400  using similar encryption if necessary. Thus, the mobile device  300  sends data to a specific database in the information system. Such a database relates to the user medical file. The transmission of the new updated data to this database provides an update of the user medical file. The data may then be used to determine the health status and possible treatment requirement for the user. Any transmission relating to patient or user data will be effected using appropriate security measures. 
         [0034]    One of the particular advantages of the present invention is the fact that the sensor has stored thereon a private encryption key which is used to authenticate the sensor with a receiver (i.e. mobile device). Also the private encryption key ensures that all data that “leaves” the patient or user is encrypted. Before authentication all data is stored on the sensor and is only transmitted after authentication. This provides a very high level of security for the user data. This is essential for patient confidentially and medical/patient acceptance of wireless communication as a means for transmitting medical and other private data. 
         [0035]    It will be appreciated that embodiment of this invention may be varied in many different ways and still remain within the intended scope and spirit of the invention. 
         [0036]    Furthermore, a person skilled in the art will understand that some or all the functional entities as well as the processes themselves may be embodied in software, or one or more software-enabled modules and/or devices. Also process steps may be carried out by appropriate and equivalent modules even if these are not identified herein per se.