Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
  • G06F21/30—Authentication, i.e. establishing the identity or authorisation of security principals
  • G06F21/31—User authentication
  • G06F21/34—User authentication involving the use of external additional devices, e.g. dongles or smart cards
  • G06F21/35—User authentication involving the use of external additional devices, e.g. dongles or smart cards communicating wirelessly
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/0723—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
  • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
  • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W12/00—Security arrangements; Authentication; Protecting privacy or anonymity
  • H04W12/06—Authentication

Definitions

• the present invention relates to a system and a method for processing a certification of a digital content and a computer-readable medium having thereon a program performing a function embodying the same, and more particularly to a system and a method for processing a certification of a digital content and a computer-readable medium having thereon a program performing a function embodying the same wherein an authentication of a digital content is carried out using a random number to prevent an interception of authentication information through a monitoring of a communication between a radio frequency identification tag and a digital content processing apparatus, and an authenticity of the radio frequency identification tag is verified based on a response to the random number.
• Background Art
• a radio frequency identification (hereinafter referred to as RFID) system processes an information by identifying a data stored in a thin planar tag attached to an object in a contactless manner through a radio signal.
• the RFID system comprises an antenna, the tag, also referred to as a transponder, and a transceiver generally integrated into a reader.
• the reader uses a radio frequency wave in order to transmit a signal for activating the tag.
• the tag transmits the data stored therein to the reader through the antenna when activated.
• the tag stores the information on a content of an object or a condition of its surroundings in an internal memory and transmits the information to the reader.
• the tag (hereinafter referred to as RFID tag) utilizes the radio frequency wave as a means for providing the information stored therein.
• the RFID tag generally includes the antenna connected to a memory device such as an integrated circuit in order to transmit a signal corresponding to a read request signal from the reader.
• a memory device such as an integrated circuit
• the RFID tag may be classified into an active RFID tag which operates using a built- in power supply and a passive RFID tag which operates by receiving a power from the read request signal.
• the RFID system is disadvantageous in that the RFID system cannot be used to authenticate software due to the fragility in its security.
• the software is sold in a form of a storage media such as a compact disc.
• the storage media such as the compact disc is highly suitable as a storage means for a digital signal.
• the digital signal stored in the storage media is advantageous in that a quality thereof is identical to that of an original even after multiple duplications.
• a drawback of the digital signal stored in the storage media is that anyone can copy the digital signal to a similar storage media for use. That is, the signal quality of the copied digital signal is identical to that of the original. Therefore, the software is vulnerable to a copyright infringement.
• a scheme wherein a copy protection device is added may be employed.
• the copy protection device having therein an information required for executing the software is connected to a parallel port of a computer.
• the computer then inspects the parallel port to detect a presence of the copy protection device when the software is executed.
• the storage media such as a DVD, a blu-ray disc and a HD-DVD having therein a movie content as well as the software may be illegally copied by the user.
• Internet such as the software and a multimedia content is hereinafter referred to as
• digital content processing apparatus An apparatus capable of carrying out a signal processing in order to reproduce or execute the digital content is hereinafter referred to as "digital content processing apparatus"
• digital content processing apparatus may be a computer executing the software.
• the digital content processing apparatus may also be a playback apparatus for reproducing the multimedia content such as a movie stored in the storage media.
• the digital content processing apparatus may be a playback apparatus capable of storing and reproducing the digital content such as a portable MP3 player.
• the digital content processing apparatus herein is capable of reading or storing the digital content and of executing or reproducing the digital content.
• An efficient method for preventing the illegal copying and an illegal use of the digital content in the digital content processing apparatus is necessary in order to protect a copyright holder of the digital content.
• a conventional authentication method of a digital content, particularly a method using an RFID has following disadvantages.
• An RFID reader which is embodied to be included in or to be connected to the digital content processing apparatus reads an information stored in an RFID tag in order to authenticate the digital content.
• another RFID reader may monitor the information. Therefore, the information related to the authentication may be intercepted.
• an undesired interception of the information limits a use of an RFID reader
• a digital content authentication processing system comprising a digital content processing apparatus; and a radio frequency identification tag; wherein the digital content processing apparatus comprises: an authentication query signal generator for generating an authentication query signal for authenticating a digital content using a random number; a radio communication unit for transmitting the authentication query signal to the radio frequency identification tag and for receiving an authentication response signal corresponding to the authentication query signal from the radio frequency identification tag; and an authentication unit for authenticating the digital content based on the authentication query signal and the authentication response signal, and wherein the radio frequency identification tag comprises: an authentication response signal generator for generating the authentication response signal based on the authentication query response signal for authenticating the digital content; and a tag radio communication unit for receiving the authentication query signal from the digital content processing apparatus and for transmitting the authentication response signal to the digital content processing apparatus.
• the authentication unit further comprises an authentication comparison signal generator for generating an authentication comparison signal based on the authentication query signal, wherein the authentication comparison signal generator generates the authentication comparison signal from the authentication query signal based on a first transfer function, and the authentication response signal generator generates the authentication response signal from the authentication query signal based on a second transfer function being identical to or conforming to the first transfer function, and wherein the authentication unit determines the digital content to be authentic when the authentication query signal corresponding to the authentication comparison signal.
• an authentication comparison signal generator for generating an authentication comparison signal based on the authentication query signal
• the authentication comparison signal generator generates the authentication comparison signal from the authentication query signal based on a first transfer function
• the authentication response signal generator generates the authentication response signal from the authentication query signal based on a second transfer function being identical to or conforming to the first transfer function
• the authentication unit determines the digital content to be authentic when the authentication query signal corresponding to the authentication comparison signal.
• the digital content processing apparatus further comprises a device password storage for storing a device authentication password for authenticating the digital content; wherein the authentication comparison signal generator generates the authentication comparison signal based on a device authentication password and the authentication query signal, wherein the radio frequency identification tag further comprises a tag password storage for storing a tag authentication password for authenticating the digital content, and wherein the authentication response signal generator generates the authentication response signal based on the tag authentication password and the authentication query signal.
• the authentication response signal generator generates the authentication response signal by irreversibly converting the tag authentication password and the authentication query signal based on the second transfer function.
• the digital content processing apparatus further comprises a user input receiver for receiving a user input, and wherein the device password storage stores the device authentication password received through the user input receiver.
• the device authentication password is displayed on a computer-readable medium corresponding to the digital content or the radio frequency identification tag.
• the device password storage stores the device authentication password from an external apparatus connected through a network.
• the device password storage reads the device authentication password from a computer-readable medium to be stored therein.
• the tag password storage stores the tag authentication password in a manner that the password is unreadable by an external apparatus.
• the device authentication password corresponding to the tag authentication password.
• a digital content authentication processing method a digital content authentication processing system, the digital content authentication processing system including a digital content processing apparatus and a radio frequency identification tag, the method comprising steps of: (a) generating an authentication query signal for authenticating a digital content using a random number; (b) transmitting the authentication query signal to the radio frequency identification tag; (c) receiving an authentication response signal from the radio frequency identification tag as of response to the authentication query signal; and (d) authenticating the digital content based on the authentication query signal and the authentication response signal.
• the step (a) comprises generating the random number within a predetermined range to be designated as the authentication query signal.
• the method in accordance with the present invention may further comprise (e) generating an authentication comparison signal by converting the authentication query signal based on a transfer function, and wherein the step (d) comprises comparing the authentication comparison signal with the authentication response signal.
• the method in accordance with the present invention may further comprises (f) storing the device authentication password generating the authentication comparison signal prior to carrying out the step (a), wherein the step (e) comprises generating the authentication comparison signal by irreversibly converting the device authentication password and the authentication query signal based on the transfer function.
• a digital content authentication processing method a digital content authentication processing system, the digital content authentication processing system including a digital content processing apparatus and the radio frequency identification tag, the method comprising steps of: (a) receiving an authentication query signal from the digital content processing apparatus; (b) generating an authentication response signal by converting the authentication query signal based on a transfer function; and (c) transmitting the authentication response signal to the digital content processing apparatus.
• the method in accordance with the present invention may further comprises (d) storing a tag authentication password for generating of the authentication response signal prior to carrying out the step (a), wherein the step (b) comprises generating the authentication response signal by irreversibly converting the authentication query signal and the tag authentication password based on the transfer function.
• the step (d) comprises storing the tag authentication password in a manner that the password is unreadable by an external apparatus.
• an authentication of a digital content is carried out using a random number to prevent an interception of an authentication information through a monitoring of a communication between a radio frequency identification tag and a digital content processing apparatus, and a authenticity of the radio frequency identification tag is verified base on a response to the random number.
• FIG. 1 is a block diagram exemplifying a digital content authentication processing system in accordance with the present invention.
• FIG. 2 is a flow diagram illustrating a digital content authentication processing method in accordance with an embodiment of the present invention.
• FIG. 3 is a flow diagram illustrating a digital content authentication processing method in accordance with another embodiment of the present invention.
• FIG. 1 is a block diagram exemplifying a digital content authentication processing system in accordance with the present invention.
• the digital content authentication processing system in accordance with the present invention comprises a digital content processing apparatus 100 and a radio frequency identification tag 200.
• the digital content processing apparatus 100 shown in Fig. 1 comprises an authentication query signal generator 110, a radio communication unit 130 and an authentication unit 150.
• the digital content processing apparatus 100 shown in Fig. 1 may further comprise a device password storage 170.
• the digital content processing apparatus 100 may further comprise a user input receiver (not shown).
• the radio frequency identification tag 200 shown in Fig. 1 comprises an authentication response signal generator 210 and a tag radio communication unit 230.
• the radio frequency identification tag 200 shown in Fig. 1 may further comprise a tag password storage 250.
• the authentication query signal generator 110 generates an authentication query signal.
• the digital content processing apparatus 100 transmits the authentication query signal to the radio frequency identification tag 200, and the digital content processing apparatus 100 receives an authentication response signal corresponding to the authentication query signal from the radio frequency identification tag 200.
• the authentication query signal may use a random number generated to be within a predetermined range.
• the radio frequency identification tag 200 generates a signal corresponding to the authentication query signal through an internal signal processing, i.e., is the authentication response signal, to be transmitted to the digital content processing apparatus 100.
• the digital content processing apparatus 100 may verify the authentication of the radio frequency identification tag 200 based on the authentication response signal.
• the random number is used as the authentication query signal in order to prevent other readers from monitoring a communication between the digital content processing apparatus 100 and the radio frequency identification tag 200. That is, the authentication query signal, which is changed randomly, is used to prevent adjacent tags or adjacent readers from knowing the authentication response signal despite the monitoring.
• the radio communication unit 130 transmits the authentication query signal generated by the authentication query signal generator 110 to the radio frequency identification tag 200.
• the radio communication unit 130 receives the authentication response signal, which is the response to the authentication query signal, from the radio frequency identification tag 200. That is, the radio communication unit 130 carries out an interfacing for a radio frequency identification communication.
• the authentication unit 150 authenticates the digital content based on the authentication query signal generated by the authentication query signal generator 110 and the authentication response signal received from the radio communication unit 130.
• the authentication unit 150 may comprise an authentication comparison signal generator (not shown) generating an authentication comparison signal based on the authentication query signal generated by the authentication query signal generator 110 for authenticating of the digital content.
• the authentication unit 150 compares the authentication comparison signal generated by the authentication comparison signal generator with the authentication query signal received from the radio frequency identification tag 200 to authenticate the digital content. That is, the authentication comparison signal generator generates the authentication comparison signal, which is identical to or corresponds to the authentication response signal generated by the radio frequency identification tag and transmitted to the digital content processing apparatus 100.
• a first transfer function used by theauthentication comparison signal generator is identical to or conforms to a second transfer function used by the authentication response signal generator 210 of the radio frequency identification tag 200.
• the digital content processing apparatus 100 may only execute the digital content authenticated through the authentication unit 150.
• radio frequency identification tag 200 is described in more detail below.
• the authentication response signal generator 210 generates the authentication response signal based on the authentication query signal received from the digital content processing apparatus 100. That is, the authentication response signal generator 210 generates the authentication response signal using a transfer function when the authentication response signal generator 210 receives the authentication query signal.
• the second transfer function used by authentication response signal generator 210 is identical to or conforms to the first transfer function used by the authentication comparison signal generator of the digital content processing apparatus 100.
• the tag radio communication unit 230 receives the authentication query signal from the digital content processing apparatus 100. In addition, the tag radio communication unit 230 transmits the authentication query signal generated by the authentication response signal generator 210 to the digital content processing apparatus 100. That is, the tag radio communication unit 230 carries out an interfacing for a radio frequency identification communication.
• the authentication comparison signal generator and the authentication response signal generator 210 may use the first transfer function and the second transfer function, respectively as described above, which are identical to or conform to each other.
• the authentication comparison signal generator may generate the authentication comparison signal using a function Fl(Nl).
• the authentication response signal generator 210 may generate the authentication response signal also using the function Fl(Nl).
• the first transfer function is identical to the second transfer function.
• the function Fl(x) is a transfer function for converting x, and a value of Fl(x) is the authentication comparison signal or the authentication response signal.
• the authentication comparison signal generator may generate the authentication comparison signal using the function Fl(Nl), which is the first transfer function
• the authentication response signal generator 210 may generate the authentication response signal using the function F2(N1), which is the second transfer function.
• the functions Fl(x) and F2(x) are the transfer functions for converting x.
• the values of Fl(x) and F2(x) are the authentication comparison signal and the authentication response signal, respectively.
• the functions Fl(x) and F2(x) may be configured in a manner that there exists a correlation between the values of Fl(x) and F2(x).
• the comparison by the authentication unit 150 may be carried out even when the authentication comparison signal generator of the digital content processing apparatus 100 and the authentication response signal generator 210 of the radio frequency identification tag 200 do not use the identical transfer function.
• the authentication unit 150 determines the digital content to be authentic when the authentication response signal and the authentication comparison signal are identical to (that is, when the identical transfer function is used) or conform to (that is, when the transfer functions having the correlation are used) each other by comparing the authentication response signal with the authentication comparison signal.
• the authentication response signal generator 210 of the radio frequency identification tag 200 generates the authentication response signal based on the authentication query signal. Particularly, the authentication response signal changes according the authentication query signal because the authentication query signal includes the random number.
• radio frequency identification tag 200 since the radio frequency identification tag 200 generates the authentication response signal based on the random number, other adjacent tags cannot know the authentication response signal. Therefore, an authenticity of the radio frequency identification tag 200 is certified.
• the digital content processing apparatus 100 may further comprise the device password storage 170 for storing a device authentication password for authenticating the digital content.
• the radio frequency identification tag 200 may further comprise the tag password storage 250 for storing a tag authentication password for authenticating the digital content.
• the device authentication password and the tag authentication password are used to improve a security of the authentication process.
• the authentication comparison signal generator generates the authentication comparison signal based on the device authentication password of the device password storage 170 and the authentication query signal of the authentication query signal generator 110.
• the authentication response signal generator 210 generates the authentication response signal based on the tag authentication password of the tag password storage 250 and the authentication query signal.
• the device authentication password stored in the device password storage 170 and the tag authentication password stored in the tag password storage 250 may be identical to or correspond to each other. That is, an authentication password identical to the tag authentication password or corresponding to the tag authentication password by n: 1 is stored in the device password storage 170 of the digital content processing apparatus 100 as the device authentication password. For instance, the device authentication password may correspond to a plurality of the tag authentication password.
• the digital content processing apparatus 100 may further comprise the user input receiver for receiving a user input.
• the user input receiver receives the user input through an input device such as a keyboard.
• the authentication password may be printed on a surface of the compact disc or on a case thereof. Alternately, the authentication password may be printed on the radio frequency identification tag 200 provided with the compact disc.
• the device password storage 170 stores the device authentication password received by the user input receiver. Moreover, the tag authentication password may be prestored in the radio frequency identification tag 200.
• the device password storage 170 may store the device authentication password received from an external apparatus through a network.
• the digital content processing apparatus 100 connects to the external apparatus storing the device authentication password corresponding to the tag authentication password of the radio frequency identification tag 200 through the network to receive device authentication password.
• the device password storage 170 stores the received device authentication password.
• the tag authentication password may be prestored in the radio frequency identification tag 200.
• the device password storage 170 reads the device authentication password stored in the storage media storing the digital content, i.e. the compact disc, to store the device authentication password. That is, the device authentication password is prestored in the storage media such as the compact disc during the manufacturing process thereof, and the digital content processing apparatus 100 reads the device authentication password.
• the device password storage 170 stores the device authentication password read from the storage media.
• the tag authentication password corresponding to the device authentication password is prestored in the radio frequency identification tag 200.
• the device authentication password of the device password storage 170 may be identical to the tag authentication password of the tag password storage 250 or correspond to the tag authentication password by n:l.
• the tag password storage 250 may store the tag authentication password in a manner that the password is unreadable by the external apparatus.
• the tag authentication password is stored in a manner that other adjacent readers cannot read the tag authentication password stored in the tag password storage 250 included in the radio frequency identification tag 200 even when the radio frequency identification tag 200 is communicating with other adjacent readers.
• the authentication comparison signal generator generates the authentication comparison signal based on the device authentication password of the device password storage 170 and the authentication query signal of the authentication query signal generator 110.
• the authentication response signal generator 210 generates the authentication response signal based on the tag authentication password of the tag password storage 250 and the authentication query signal received from the authentication query signal generator 110.
• the authentication comparison signal and the authentication response signal are thereby expressed as F3(N1, PW).
• the conversion by the function F3(x, y) used by the authentication response signal generator 210 may be irreversible. That is, the function F3(x, y) may be an irreversible transfer function.
• the irreversible transfer function refers to the function wherein the input value of the transfer function cannot be known even when the authentication response signal is known. Therefore, when the irreversible transfer function is used, other adjacent tags or readers cannot know the authentication password PW even when other adjacent tags or readers know the authentication query signal and the transfer function by monitoring the communication.
• FIG. 2 is a flow diagram illustrating a digital content authentication processing method in accordance with an embodiment of the present invention.
• FIG. 2 illustrates a digital content authentication processing method carried out in the digital content processing apparatus of the digital content authentication processing system including the digital content processing apparatus and the radio frequency identification tag described with reference to Fig. 1.
• a portion of a detailed description of the method shown in Fig. 2 already described with reference to Fig. 1 is omitted.
• the digital content processing apparatus generates the authentication query signal to be transmitted to the radio frequency identification tag (Sl 10).
• the authentication query signal is generated by generating the random number.
• the random number may be generated by arbitrarily selecting a number.
• the digital content processing apparatus transmits the authentication query signal generated in the step Sl 10 to the radio frequency identification tag (S130).
• the digital content processing apparatus receives the authentication response signal, which is a response to the authentication query signal, from the radio frequency identification tag to correspond to the transmission in the step S 130 (S 150).
• the digital content processing apparatus authenticates the digital content based on the authentication query signal generated in the step Sl 10 and the authentication response signal received in the step S 150 (S 170).
• the method may further comprise generating the authentication comparison signal by converting the authentication query signal based on the transfer function.
• the authentication comparison signal is generated for the authentication in the step S 170.
• the digital content processing apparatus compares the generated authentication comparison signal with the authentication response signal received in the step S 150 to carry out the authentication in the step S 170.
• the radio frequency identification tag converts the authentication query signal using the transfer function for generating the authentication comparison signal
• the authentication response signal may be generated.
• the authentication of the digital content is possible when the digital content processing apparatus determines whether the authentication comparison signal is identical to the authentication response signal in the step S 170.
• the method may further comprise storing the device authentication password for generating the authentication comparison signal prior to carrying out the step Sl 10.
• the device authentication password is used to improve the security of the authentication process.
• the digital content processing apparatus may generate the authentication comparison signal from the device authentication password and the authentication query signal based on the irreversible transfer function as described above in the step of generating the authentication response signal.
• the radio frequency identification tag may generate the authentication response signal from the tag authentication password, which is stored in the radio frequency identification tag to correspond to the device authentication password, and the authentication query signal based on the irreversible transfer function.
• the digital content processing apparatus may carry out the authentication of the digital content by determining whether the authentication comparison signal is identical to the authentication response signal in the step S 170.
• FIG. 3 is a flow diagram illustrating a digital content authentication processing method in accordance with another embodiment of the present invention.
• FIG. 3 illustrates a digital content authentication processing method carried out in the radio frequency identification tag of the digital content authentication processing system including the digital content processing apparatus and the radio frequency identification tag described with reference to Fig. 1.
• a portion of a detailed description of the method shown in Fig. 3 already described with reference to Fig. 1 is omitted.
• the radio frequency identification tag receives the authentication query signal from the digital content processing apparatus (S210).
• the radio frequency identification tag generates the authentication response signal by converting the authentication query signal received in the step S210 based on the irreversible transfer function (S230).
• the radio frequency identification tag transmits the authentication response signal generated in the step S230 to the digital content processing apparatus (S250).
• the tag authentication password for generating the authentication response signal may be stored in the radio frequency identification tag prior to carrying out the step S210.
• the tag authentication password is used to improve the security of the authentication process.
• the radio frequency identification tag may generate the authentication response signal by converting the authentication query signal and the tag authentication password based on the irreversible transfer function.
• the tag authentication password is stored in a manner that the password is unreadable by the external apparatus.
• the tag authentication password used for generating the authentication response signal is stored in the radio frequency identification tag in a manner that other external adjacent readers cannot read the tag authentication password.
• the present invention provides a computer-readable medium having thereon a program performing function embodying the digital content authentication processing method based on the radio frequency identification tag in accordance with the present invention.
• the computer-readable medium refers to various storage mediums for storing a data in a code or a program format that may be read by a computer system.
• the computer- readable medium may include a memory such as a ROM and a RAM, a storage medium such as CD-ROM and a DVD-ROM, a magnetic storage medium such as a magnetic tape and a floppy disk, and an optical data storage medium.
• the computer- readable medium may include a data transferred via the Internet.
• the computer- readable medium may be embodied by a computer-readable data divided and stored over computer systems connected through a network.
• an authentication of a digital content is carried out using a random number to prevent an interception of authentication information through a monitoring of a communication between a radio frequency identification tag and a digital content processing apparatus, and a authenticity of the radio frequency identification tag is verified base on a response to the random number.

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Citations (4)

• 2007
  • 2007-07-02 KR KR1020070065974A patent/KR20090002547A/ko not_active Application Discontinuation
• 2008
  • 2008-07-02 WO PCT/KR2008/003898 patent/WO2009005296A2/en active Application Filing

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