JP2005286595A - Radio transmission apparatus, mutual authentication method, and mutual authentication program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio transmission apparatus, a mutual authentication method, and a mutual authentication program whereby mutual authentication with excellent confidentiality can be attained with a simple configuration. <P>SOLUTION: Apparatuses A, B respectively write their own apparatus ID numbers "apparatus ID-A" and "apparatus ID-B" to recording media 20A, 20B and thereafter exchange the recording media 20A, 20B. Control sections 4a, 4b respectively read the apparatus ID numbers, the "apparatus ID-B" and the "apparatus ID-A" from the recording media 20B, 20A and temporarily store the apparatus ID numbers to nonvolatile storage sections 5a, 5b. In an authentication communication mode, the apparatuses A, B use their own apparatus ID numbers as keys, encrypt their own radio section MAC addresses and transmit the result. Further, the apparatuses A, B decrypt the received data by using the apparatus ID number of the transmission opposite party as a key and acquire the radio section MAC address of the apparatus of the transmission opposite party to terminate the authentication mode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wireless transmission device, a mutual authentication method, and a mutual authentication program, and more specifically, a wireless transmission device that performs mutual authentication when wirelessly transmitting a video signal and an audio signal (hereinafter also referred to as AV data), The present invention relates to a mutual authentication method and a mutual authentication program performed in such a wireless transmission device.

  In recent years, the home network field has attracted a great deal of attention, and technical development for establishing a wireless home network has been actively conducted. As one example, in a limited space such as in a home or office, between an AV data playback device such as a video or DVD (Digital Versatile Disc) player and an AV data display device such as a television or projector. Wireless AV transmission devices that connect wirelessly have been developed.

  FIG. 7 is a schematic diagram for explaining a general usage pattern of the wireless AV transmission device.

  Referring to FIG. 7, AV data display devices 40 a to 40 c (for example, a television) are installed on each floor of home 80. On the first floor, an AV data playback device 50a (for example, a video) is connected to the AV data display device 40a. Wireless AV transmission devices 70a to 70c are connected to the AV data reproducing device 30a and the AV data display devices 40b and 40c, respectively.

  In such a configuration, in the normal communication mode, AV data reproduced by the AV data reproducing device 50a provided on the first floor is wired to the AV data display device 40a and wirelessly transmitted by the wireless AV transmission device 70a. It is converted into a signal and transmitted to the wireless AV transmission devices 70b and 70c installed on the second and third floors, respectively.

  Further, when the transmitted wireless signal is received by the wireless AV transmission devices 70b and 70c, it is converted into the original AV data and output from the AV data display devices 40b and 40c, respectively.

  Here, as shown in FIG. 7, in order to accurately connect the AV data signal reproduction device desired by the user and the AV data display device, prior to the radio transmission between the radio AV transmission devices arranged in each. Mutual authentication is required. This is because AV data is transmitted wirelessly and, unlike wired transmission, can be received by an unspecified number of wireless AV transmission devices, such as other wireless AV transmission devices in other homes.

  This mutual authentication operation has been conventionally developed in the technical field of a wireless local area network (LAN) adopted for data transmission between terminal devices such as a PC (Personal Computer). 1.

  FIG. 8 is a configuration diagram for explaining the mutual authentication method described in Patent Document 1.

  Referring to FIG. 8, information carrier 100 such as an IC card device and center-managed information processing device 110 perform mutual authentication in which each other confirms the other party when performing information communication.

  Specifically, first, the information carrier 100 transmits the unique data ID stored in advance in the first storage unit 101 to the information processing apparatus 110 serving as a communication partner using the first transmission unit 108. The unique data ID is data unique to each information carrier and is managed by the information processing apparatus 110.

  The information processing apparatus 110 generates a master key km unique to each information carrier by the data processing means 112 from the received unique data ID and the center key stored in the third storage means 111. That is, one master key km is generated corresponding to one unique data ID. This master key km is stored in advance in the second storage means 102 of the information carrier 100.

  Further, the information processing apparatus 110 uses the key generation unit 116 to randomly create a session key ks. The second encryption unit 113 encrypts the session key ks with the master key km obtained from the data processing unit 1112. The encrypted data Ekm [ks] is transmitted to the information carrier 100 by the second transmission means 118.

  Next, when the information carrier 100 receives the encrypted data Ekm [ks], the first decryption unit 103 decrypts the encrypted data Ekm [ks] using the master key km stored in the second storage unit 102.

  Further, the session key ks that is the decrypted data is transferred to the first encryption means 105. The first encryption unit 105 encrypts the combined data from the combining unit 104 using the session key ks as a key. The encrypted combined data Eks [R‖ID] is transmitted to the information processing apparatus 110 through the first transmission means 108. Here, the combined data Eks [R‖ID] is obtained by sequentially connecting the unique data ID stored in the first storage unit 101 and the random number R generated by the random number generation unit 106.

  The information processing apparatus 110 uses the second decryption unit 115 to decrypt the combined data Eks [R‖ID] using the session key ks. The decrypted data R‖ID is separated into a random number R ′ and a unique data ID ′ by the separating unit 114.

  The second comparison means 117 compares the unique data ID 'with the first received unique data ID to authenticate the information carrier 100. At this time, if the two data do not match, the information carrier 100 is rejected as having some sort of fraud.

  In the information carrier 100, the first comparison unit 107 compares the received random number R ′ with the random number R generated by the random number generation unit 106 to authenticate the information processing apparatus 110. At this time, if the two do not match, the information processing apparatus 110 is rejected as having some sort of fraud.

Only when the other party is authenticated by the above operation, information communication is possible between the two. Subsequent communication is performed using the session key ks.
Japanese Patent Publication No. 6-87234

  The conventional mutual authentication method generates a master key and a session key in an information processing apparatus, and exchanges information encrypted using these keys with an information carrier, so that high security can be maintained. .

  However, each device has to perform complicated and sophisticated processing using a complicated encryption method, making it difficult to apply to a wireless home network that is expected to rapidly spread in the future.

  Therefore, in order to enhance the versatility of the wireless AV transmission device, it is necessary to ensure a high security with a simple mutual authentication method.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a wireless transmission device, a mutual authentication method, and a mutual authentication program capable of mutual authentication excellent in confidentiality with a simple configuration.

  According to an aspect of the present invention, a wireless transmission device that wirelessly transmits a video signal and an audio signal includes an identifier unique to the wireless transmission device and wireless unit identification information unique to the wireless transmission device. Includes a mutual authentication unit that mutually authenticates a transmission partner between wireless transmission devices that perform wireless transmission, and a wireless transmission unit that wirelessly transmits a video signal and an audio signal between the authenticated wireless transmission devices. The mutual authentication means uses an identifier unique to the wireless transmission device as a transmission partner as the second identifier, an identifier storage means for storing the second identifier in a nonvolatile manner, and an identifier unique to the own wireless transmission device as the first identifier. And the first identifier as a key, the encryption means for encrypting the wireless part identification information, the identification information transmitting means for transmitting the encrypted wireless part identification information, and the received wireless transmission device of the transmission partner Authentication means for decrypting the unique wireless part identification information using the second identifier as a key and extracting the unique wireless part identification information for the transmission partner wireless transmission apparatus; and the wireless means unique to the extracted transmission partner wireless transmission apparatus Identification information storage means for storing the part identification information in a nonvolatile manner.

  Preferably, the identifier storage means includes an identifier writing means for writing the first identifier on a detachable recording medium, and an identifier reading means for reading the second identifier from the recording medium acquired from the wireless transmission device of the transmission partner. Including.

  According to another aspect of the present invention, there is provided a mutual authentication method for mutually authenticating transmission partners between a first wireless transmission device and a second wireless transmission device that perform wireless transmission, the first wireless transmission device. Includes a first identifier unique to the first wireless transmission device, first wireless unit identification information, and a first nonvolatile storage unit, and the second wireless transmission device is unique to the second wireless transmission device. Including a second identifier, second wireless unit identification information, and a second non-volatile storage unit, and writing the second and first identifiers to the first and second non-volatile storage units, respectively The first wireless transmission device encrypts and transmits the first wireless unit identification information using the first identifier as a key, and the second wireless transmission device receives the received first wireless unit identification information. Decrypting with the second identifier as a key, the first wireless unit identification information Extracting the second wireless unit identification information using the second identifier as a key and transmitting the second wireless unit identification information in the second wireless transmission device, and receiving the first received in the second wireless transmission device Decoding the wireless unit identification information using the first identifier as a key, extracting the first wireless unit identification information, and extracting the second and first wireless unit identifications into the first and second nonvolatile storage units Storing each of the information.

  Preferably, the steps of writing the second and first identifiers to the first and second nonvolatile storage units respectively include first and second attached to each of the first and second wireless transmission devices. Writing the first and second identifiers to the recording medium, exchanging the first and second recording media between the first and second wireless transmission apparatuses, And reading and temporarily storing the second and first identifiers from the second and first recording media newly attached to each of the second wireless transmission devices.

  According to another aspect of the present invention, there is provided a mutual authentication program for mutually authenticating transmission partners between a first wireless transmission device and a second wireless transmission device that perform wireless transmission. The wireless transmission device includes a first identifier unique to the first wireless transmission device, first wireless unit identification information, and a first nonvolatile storage unit, and the second wireless transmission device performs second wireless transmission. A second identifier unique to the device, a second wireless unit identification information, and a second nonvolatile storage unit, and the second and first identifiers are written to the first and second nonvolatile storage units, respectively. A step of encrypting and transmitting the first wireless unit identification information using the first identifier as a key in the first wireless transmission device, and the first wireless unit received in the second wireless transmission device Decrypt identification information using second identifier as key Extracting the first wireless unit identification information; encrypting and transmitting the second wireless unit identification information using the second identifier as a key in the second wireless transmission device; and second wireless transmission In the apparatus, the received first wireless unit identification information is decrypted using the first identifier as a key, the first wireless unit identification information is extracted, and the extracted first and second nonvolatile storage units 2 and the step of storing the first wireless unit identification information, respectively.

  Preferably, the steps of writing the second and first identifiers to the first and second nonvolatile storage units respectively include first and second attached to each of the first and second wireless transmission devices. Writing the first and second identifiers to the recording medium, exchanging the first and second recording media between the first and second wireless transmission apparatuses, And reading and temporarily storing the second and first identifiers from the second and first recording media newly attached to each of the second wireless transmission devices.

  According to the present invention, since the authentication operation is performed only with the wireless AV transmission device whose device ID number is known, it is possible to avoid misidentification interference with other homes and offices at the time of mutual authentication, in the wireless AV transmission system. High security can be maintained.

  Further, since the device ID number of the transmission partner can be easily recorded using a recording medium as a medium, it is possible to easily perform mutual authentication without requiring complicated processing means.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

  FIG. 1 is a functional block diagram showing an overall configuration of a wireless AV transmission device according to the embodiment of the present invention.

  Referring to FIG. 1, a wireless AV transmission device 10 transmits and receives wireless signals to a video / audio input / output unit 1 to which AV data is input / output and to a wireless AV transmission device (not shown) as a counterpart for wireless transmission. The wireless unit 2 and the antenna 3, the control unit 4 that controls the entire device, the nonvolatile storage unit 5 that stores a device ID number to be described later in a nonvolatile manner, the media slot 6 to which the recording medium 20 can be attached and detached, and not shown. A remote controller control unit that transmits control information included in an infrared signal emitted from a remote controller (hereinafter also referred to as a remote controller) to the control unit;

  The video / audio input / output unit 1 includes an AV data signal output terminal and an AV data signal input terminal (not shown). For example, in the usage pattern shown in FIG. 7, when the wireless AV transmission device 10 is connected to the AV data display devices 40b and 40c, the AV data signal output terminal not shown is the AV data of the AV data display devices 40b and 40c. Each is coupled to an input terminal (not shown). As a result, the video / audio input / output unit 1 of the wireless AV transmission device 10 corresponds to AV data received from the AV data reproducing device 50a via the wireless AV transmission devices 70a and 70b or the wireless AV transmission devices 70a and 70c. The data is transferred to the data display devices 40b and 40c.

  On the other hand, when the wireless AV transmission device 10 is connected to the AV data reproducing device 50a of FIG. 7, an AV data signal input terminal (not shown) is coupled to an AV data signal output terminal (not shown) of the AV data reproducing device 50a. The Thereby, the video / audio input / output unit 1 of the wireless AV transmission device 10 receives the AV data reproduced by the AV data reproducing device 50a.

  The radio unit 2 converts the AV data input to the video / audio input / output unit 1 into a radio signal, outputs the radio signal from the antenna 3, and transmits the radio signal from the radio AV transmission device 10 of the transmission partner received by the antenna 3. Is restored to the original AV data and transferred to the video / audio input / output unit 1.

  The nonvolatile storage unit 5 stores a device ID number that is an identifier unique to the wireless AV transmission device 10 in a nonvolatile manner. The nonvolatile storage unit 5 is configured by a nonvolatile memory or hardware such as a flash memory or an EEPROM (electrically erasable programmable read only memory).

  In addition to controlling the entire device, the control unit 4 writes / reads the device ID number to / from the nonvolatile storage unit 5. The controller 4 can also write / read data to / from the recording medium 20 inserted in the media slot 6.

  Here, the wireless transmission of AV data performed by the wireless AV transmission device 10 of FIG. 1 will be described. FIG. 2 is a schematic diagram for explaining the wireless transmission of AV data performed between two wireless AV transmission devices 10 (for example, 10a and 10b).

  Referring to FIG. 2, wireless AV transmission device 10a is connected to AV data display device 40a in video / audio input / output unit 1a. The wireless AV transmission device 10b is connected to the AV data reproducing device 50b in the video / audio input / output unit 1b.

  First, a user who wants to view AV data on a desired AV data display device 40a operates a remote control 30a to provide a control signal that instructs the wireless AV transmission device 10a connected to the AV data display device 40a to reproduce AV data. Irradiate an infrared signal. When this infrared signal is received by the wireless AV transmission device 10a, it is converted into an electrical signal by the remote control unit 7a.

  When the electric signal is further transferred to the radio unit 2a via the control unit 4a, the electric signal is converted into a radio signal to be a control signal and transmitted from the antenna 3a. The wireless signal is received by the antenna 3b of the wireless AV transmission device 10b connected to the AV data reproducing device 50b.

  Next, in the wireless AV transmission device 10b connected to the AV data reproducing device 50b, the wireless signal received by the antenna 3b is wirelessly decoded by the wireless unit 2b and sent to the remote control unit 7b via the control unit 4b. In the remote controller 7b, the received wireless signal is duplicated into an infrared signal and output from the infrared light emitting module 60b. When the AV data reproducing device 50b receives an infrared signal in an internal remote control receiver (not shown), the AV data reproducing device 50b recognizes the control signal based on the infrared signal and performs an operation instructed by the user.

  The AV data reproducing device 50b transmits the reproduced AV data to the wireless AV transmission device 10b connected to the device. When receiving the AV data in the video / audio input / output unit 1b, the wireless AV transmission device 10b converts the AV data into a wireless signal in the wireless unit 2b and transmits the wireless signal from the antenna 3.

  Finally, when the wireless signal is received by the antenna 3a of the wireless AV transmission device 10a connected to the AV data display device 40a, the wireless signal is converted into the original AV data by the wireless unit 2a, and is transmitted from the video / audio input / output unit 1a to the AV. The data is transferred to the data display device 40a. In the AV data display device 40a, video is reproduced and displayed based on the video signal of AV data, and audio is reproduced based on the audio signal of AV data.

  As described above, by wirelessly transmitting an infrared signal and AV data, which are control signals, between a plurality of wireless AV transmission devices, the user can remotely operate the AV data playback device and perform video and audio using a desired AV data display device. Can be watched.

  Here, in order to reliably perform such an operation without malfunction, as described above, it is necessary that wireless AV transmission devices that perform wireless transmission perform mutual authentication for mutually confirming each other. The Hereinafter, a mutual authentication method between wireless AV transmission devices according to the present embodiment will be described.

  FIG. 3 is a schematic diagram for explaining a mutual authentication method in the wireless AV transmission device 10 of FIG.

  As shown in FIG. 3, the mutual authentication method according to the present embodiment includes three states (state 1, state 2, and state 3) arranged in time series. In the following, the two wireless AV transmission devices 10A and 10B that perform wireless transmission are also referred to as device A and device B, respectively.

  First, as a premise of the authentication modes shown in states 1 to 3, device A is assigned a device ID number “device ID-A”, which is an identifier unique to wireless AV transmission device 10A. Similarly, for the device B, a device ID number “device ID-B”, which is an identifier unique to the wireless AV transmission device 10B, is assigned.

  In the state 1 of FIG. 3, the recording medium 20A is inserted into the media slot 6a of the wireless AV transmission device 10A. The control unit 4a writes the device ID number “device ID-A” unique to the device A to the recording medium 20A.

  Similarly, in the wireless AV transmission device 10B, the control unit 4b writes the device ID number “device ID-B” unique to the device B to the recording medium 20B inserted into the media slot 6b.

  The device A and the device B make a transition to the state 2 in response to the respective device ID numbers being written in the corresponding recording media 20A and 20B.

  Next, in state 2, the wireless AV transmission devices 10A and 10B that perform wireless transmission replace the recording media 20A and 20B, and attach the replaced recording media 20A and 20B to their media slots 6a and 6b. That is, as shown in FIG. 3, the recording medium 20 </ b> A in which the device ID number “device ID-A” unique to the device A is written is loaded in the media slot 6 b of the device B. On the other hand, the recording medium 20B in which the device ID number “device ID-B” unique to the device B is written is loaded into the media slot 6a of the device A.

  Subsequently, the control units 4a and 4b of the device A and the device B read the device ID numbers recorded on the recording media 20A and 20B loaded, respectively. Specifically, the control unit 4a of the device A reads a device ID number “device ID-B” unique to the device B from the recording medium 20B. On the other hand, the control unit 4b of the device B reads the device ID number “device ID-A” unique to the device A from the recording medium 20A. The read device ID number is temporarily stored in the nonvolatile storage units 5a and 5b in the wireless AV transmission devices 10A and 10B.

  In the state 2, it further shifts to an authentication communication mode in which the transmission partners are mutually authenticated by using their own device ID number and the temporarily stored device ID number of the transmission partner. In the authentication communication mode, as described later, by encrypting and transmitting a wireless unit MAC address (Media Access Control address) address that is wireless unit identification information unique to the wireless AV transmission device 10 using the device ID number as a key, Only the wireless AV transmission device 10 which is the transmission partner can acquire its own wireless unit MAC address.

  Finally, as the state 3, the acquired wireless unit MAC address of the transmission partner is stored in the nonvolatile storage unit 5, and the mutual authentication operation is terminated. In the subsequent communication modes, the wireless AV transmission device 10 performs wireless transmission by designating the stored wireless unit MAC address as a destination.

  FIG. 4 is a flowchart for explaining the first half (from state 1 to the first half of state 2) of the mutual authentication operation shown in FIG.

  Referring to FIG. 4, device A writes its own device ID number “device ID-A” in recording medium 20 </ b> A mounted in the media slot inside the device (step S <b> 02).

  Next, the recording medium 20A is replaced with a wireless AV transmission device 10B (device B) as a transmission partner, and the replaced recording medium 20B is newly inserted into a media slot. The control unit 4a reads the device ID number “device ID-B” unique to the device B written in the recording medium 20B (step S04), and temporarily stores it in the nonvolatile storage unit 5a (step S05).

  Similarly, in the device B, the device ID number “device ID-A” unique to the device A is temporarily stored in the internal nonvolatile storage unit 5b according to steps S12 to S15.

  When device A and device B finish the temporary storage of the device ID numbers in steps S05 and S15, respectively, the devices A and B shift to the authentication communication mode. At this time, since the device ID number unique to itself is informed by the recording medium 20 to the other party's wireless AV transmission device 10 to be authenticated, the authentication operation is performed only with the device that knows its own device ID number. It will be.

  FIG. 5 is a flowchart for explaining the latter half of the mutual authentication operation (from the second half of state 2 to state 3) shown in FIG.

  As shown in FIG. 5, in the authentication communication mode, device A and device B encrypt and transmit the wireless unit MAC address unique to each wireless AV transmission device 10. The wireless unit MAC address is an address that is fixedly allocated to the wireless unit of each device, and the data transmission destination and destination are designated by this address. The present embodiment is characterized in that the device ID number is used as a key for encrypting the wireless unit MAC address.

  Specifically, on the device A side, the wireless unit MAC address unique to the device A is encrypted using the device ID number “device ID-A” as a key (step S21). The encrypted wireless unit MAC address is transmitted to an open address that does not specify a destination (step S22). When the device A transmits the wireless unit MAC address, the device A enters a reception waiting state for a response thereto (step S23).

  In step S23, the device A waits for a response and measures the waiting time by an internal timer means (step S24). A predetermined waiting time is set in advance in the timer means, and the reception waiting state is held until the set waiting time is reached (step S25). If no response is received within the set time, the device A ends the authentication mode (step S26).

  On the other hand, when the response is received within the set time in step S23 (step S27), the wireless unit 2 of the device A transmits the received data to the device ID number “Device ID number“ of the device B stored in the nonvolatile storage unit 5 ”. Decryption is performed using the “device ID-B” as a key (step S28). If the decryption is successful, that is, if a response from the device B whose device ID number “device ID-B” is known is confirmed, the wireless unit MAC address of the device B is extracted from the received data (step S31). .

  The device A stores the extracted wireless unit MAC address of the device B in the nonvolatile storage unit 5a as a transmission destination address (step S32). At this time, the device ID number “device ID-B” that has been temporarily stored is also stored in the nonvolatile storage unit 5a, and the authentication mode is terminated (step S33).

  On the other hand, if decryption is impossible in step S29, that is, if the response is from a device other than device B whose device ID number is not known, the authentication mode is terminated without authenticating the device on the transmission side (step S29). S30).

  On the other hand, on the device B side, the wireless unit MAC address unique to the device B is encrypted using the device ID number “device ID-B” as a key (step S41). The encrypted wireless unit MAC address is transmitted to an open address that does not specify a destination (step S42). When the device B transmits the wireless unit MAC address, the device B enters a reception waiting state for a response thereto (step S43).

  In step S43, the device B waits for a response and measures the waiting time by an internal timer means (step S44). A predetermined waiting time is set in advance in the timer means, and the reception waiting state is held until the set waiting time is reached (step S45). If no response is received within this set time, the device B ends the authentication mode (step S46).

  On the other hand, when a response is received within the set time in step S43 (step S47), the wireless unit 2 of the device B transmits the received data to the device ID number “of the device A stored in the nonvolatile storage unit 5b”. Decryption is performed using “device ID-A” as a key (step S48). If the decryption is successful (step S49), that is, if a response from the device A whose device ID number “device ID-A” is known is confirmed, the wireless unit MAC address of the device A is extracted from the received data. (Step S51).

  The device B stores the extracted wireless unit MAC address of the device A as a transmission destination address in the nonvolatile storage unit 5b (step S52). At this time, the device ID number “device ID-A” that has been temporarily stored is also stored in the nonvolatile storage unit 5b, and the authentication mode is terminated (step S53).

  On the other hand, if decryption is impossible in step S49, that is, if the response is from a device other than the device A whose device ID number is not known, the authentication mode is terminated without authenticating the transmitting device (step S49). S50).

  When the communication partner is confirmed in each of the devices A and B and the authentication mode ends, AV data is wirelessly transmitted between the device A and the device B in the normal communication mode thereafter.

  The configuration of the functional block diagram of the wireless AV transmission device 10 shown in FIG. 1 is actually executed by software by a digital signal processor (DSP) (not shown) according to the flowcharts shown in FIGS. Is. The DSP reads a program including the steps of the flowcharts shown in FIGS. 4 and 5 from a memory (not shown) and executes the program.

  FIG. 6 is a diagram for explaining a mutual authentication sequence performed between device A and device B shown in FIGS. 4 and 5.

  Referring to FIG. 6, first, devices A and B have their own device ID numbers assigned to storage media 20A and 20B installed in media slots 6a and 6b in wireless AV transmission devices 10A and 10B shown in FIG. “Device ID-A” and “Device ID-B” are written respectively (corresponding to state 1 of the mutual authentication method).

  Next, when the devices A and B exchange the recording media 20A and 20B and install them in their own media slots 6a and 6b, the device ID number “device ID−” of the transmission partner stored in the recording media 20B and 20A is stored. B ”and“ apparatus ID-A ”are read out. Furthermore, the read device ID number is temporarily stored in the nonvolatile storage units 5a and 5b, and the mode shifts to the authentication communication mode.

  In the authentication communication mode, each of the devices A and B encrypts its own wireless unit MAC address using its own device ID number as a key, and transmits the encrypted data to the open address. The encrypted data can be received by the wireless unit 2 of the wireless AV transmission device 10 other than the device A. The wireless AV transmission device 10 that has received the encrypted data attempts to decrypt it using the device ID number of the transmission partner temporarily stored in the nonvolatile storage unit 5 as a key.

  Specifically, the device A is given its own wireless unit MAC address (for example, [134.199.100.1]). The device A is further given a unique device ID number “device ID-A” (for example, [010001]).

  The device A transmits data (for example, [TfllPpoAbdlhYg]) generated by encrypting the wireless unit MAC address using its device ID number “device ID-A” as a key, from the wireless unit 2a.

  When the transmission data of the device A is received by the wireless unit 2b of the device B, the device ID number “device ID-A” stored in the nonvolatile storage unit 5b of the device B is decrypted. At this time, since the device ID number “device ID-A” (corresponding to [010001]) of the device A that is the transmission partner is already stored in the device B, the data [134 that is decrypted by this device ID number [134] 199.100.1] is obtained. This decrypted data naturally matches the wireless unit MAC address of device A. The device B authenticates the device A as a transmission partner, and stores the decrypted data in the nonvolatile storage unit 5b as the wireless unit MAC address of the device A.

  Similarly, on the device B side, the wireless unit MAC address of device B (for example, [134.199.110.25]) is used as the device ID number “device ID-B” (for example, [010002]) as a key. The encrypted data (for example, [HDWqpuHUyHtgfr]) is transmitted from the wireless unit 2b.

  When the transmission data of the device B is received by the wireless unit 2a of the device A, the device ID number “device ID-A” stored in the nonvolatile storage unit 5a of the device A is decrypted. At this time, since the device A already stores the device ID number “device ID-B” (corresponding to [010001]) of the device B as the transmission partner, the data [134 decrypted with this device ID number [134]. .199.110.25] is extracted as the wireless unit MAC address of device B and stored in the nonvolatile storage unit 5a. Device A authenticates device B as a wireless transmission partner and ends the authentication mode.

  When the authentication mode ends in each of the devices A and B, the subsequent wireless transmission is performed by designating the stored wireless counterpart MAC address as the destination.

  As described above, according to the embodiment of the present invention, the authentication operation is performed only with the wireless AV transmission device whose device ID number is known, so that false recognition interference with other homes or offices during mutual authentication is avoided. Therefore, high security can be maintained in the wireless AV transmission system.

  Further, since the device ID number of the transmission partner can be easily recorded using a recording medium as a medium, it is possible to easily perform mutual authentication without requiring complicated processing means.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a functional block diagram which shows the whole structure of the radio | wireless AV transmission apparatus according to embodiment of this invention. 2 is a schematic diagram for explaining wireless transmission of AV data performed between two wireless AV transmission devices 10. FIG. It is the schematic for demonstrating the mutual authentication method in the radio | wireless AV transmission apparatus 10 of FIG. It is a flowchart for demonstrating the first half part (from the state 1 to the first half of the state 2) of the mutual authentication operation | movement shown in FIG. FIG. 4 is a flowchart for explaining a second half (from the second half of state 2 to state 3) of the mutual authentication operation shown in FIG. 3; It is a figure explaining the mutual authentication sequence performed between the apparatus A shown in FIG. 4 and 5 and the apparatus B. FIG. It is the schematic for demonstrating the general usage pattern of a radio | wireless AV transmission apparatus. It is a block diagram for demonstrating the mutual authentication system of patent document 1. FIG.

Explanation of symbols

  1, 1a, 1b Video / audio input / output unit, 2, 2a, 2b Radio unit, 3, 3a, 3b Antenna, 4, 4a, 4b Control unit, 5, 5a, 5b Non-volatile storage unit, 6, 6a, 6b Media slot 7, 7a, 7b Remote control unit 10, 10A, 10B, 70a-70c Wireless AV transmission device, 20, 20A, 20B Recording media, 40a-40c AV data display device, 50a, 50b AV data playback device, 60b Infrared Light emitting module, 80 household, 100 information carrier, 101 first storage means, 102 second storage means, 103 first decryption means, 104 combination means, 105 first encryption means, 106 random number generation means, 107 First comparison means 108 First transmission means 110 Information processing device 111 Third storage means 112 Data processing , 113 second encryption means, 114 separation means 115 second decoding means, 116 a key generating unit, 117 second comparison means, 118 second transmission means.

Claims (6)

A wireless transmission device that wirelessly transmits a video signal and an audio signal, including an identifier unique to the wireless transmission device and wireless unit identification information unique to the wireless transmission device,
The wireless transmission device is:
Mutual authentication means for mutually authenticating transmission partners between the wireless transmission devices performing wireless transmission;
Wireless transmission means for performing wireless transmission of the video signal and audio signal with the authenticated wireless transmission device,
The mutual authentication means includes
An identifier storage means for storing the second identifier in a non-volatile manner, using the identifier unique to the wireless transmission device as a transmission partner as a second identifier;
Encryption means for encrypting the wireless unit identification information using the identifier unique to the wireless transmission device as a first identifier, and using the first identifier as a key;
Identification information transmitting means for transmitting the encrypted wireless unit identification information;
Authentication means for decrypting the received wireless part identification information unique to the transmission partner wireless transmission apparatus using the second identifier as a key and extracting the wireless part identification information unique to the transmission partner wireless transmission apparatus When,
A wireless transmission device comprising: identification information storage means for storing the wireless unit identification information unique to the extracted wireless transmission device of the transmission partner in a non-volatile manner. The identifier storage means
Identifier writing means for writing the first identifier on a removable recording medium;
The wireless transmission device according to claim 1, further comprising: an identifier reading unit that reads the second identifier from the recording medium acquired from the wireless transmission device of the transmission partner. A mutual authentication method for mutually authenticating transmission partners between a first wireless transmission device and a second wireless transmission device that perform wireless transmission,
The first wireless transmission device includes a first identifier and first wireless unit identification information unique to the first wireless transmission device, and a first nonvolatile storage unit,
The second wireless transmission device includes a second identifier and second wireless unit identification information unique to the second wireless transmission device, and a second nonvolatile storage unit,
Writing the second and first identifiers to the first and second nonvolatile storage units, respectively;
In the first wireless transmission device, encrypting and transmitting the first wireless unit identification information using the first identifier as a key;
Decrypting the received first wireless unit identification information using the second identifier as a key and extracting the first wireless unit identification information in the second wireless transmission device; and
In the second wireless transmission device, encrypting and transmitting the second wireless unit identification information using the second identifier as a key;
Decrypting the received first wireless unit identification information using the first identifier as a key and extracting the first wireless unit identification information in the second wireless transmission device; and
Storing the extracted second and first wireless unit identification information in the first and second nonvolatile storage units, respectively. The step of writing the second and first identifiers to the first and second nonvolatile storage units, respectively,
Writing first and second identifiers to the first and second recording media respectively attached to the first and second wireless transmission devices;
Exchanging the first and second recording media between the first and second wireless transmission devices;
Reading and temporarily storing the second and first identifiers from the second and first recording media newly attached to each of the first and second wireless transmission devices. The mutual authentication method according to claim 3. A mutual authentication program for mutually authenticating a transmission partner between a first wireless transmission device and a second wireless transmission device that perform wireless transmission,
The first wireless transmission device includes a first identifier and first wireless unit identification information unique to the first wireless transmission device, and a first nonvolatile storage unit,
The second wireless transmission device includes a second identifier and second wireless unit identification information unique to the second wireless transmission device, and a second nonvolatile storage unit,
Writing the second and first identifiers to the first and second nonvolatile storage units, respectively;
In the first wireless transmission device, encrypting and transmitting the first wireless unit identification information using the first identifier as a key;
Decrypting the received first wireless unit identification information using the second identifier as a key and extracting the first wireless unit identification information in the second wireless transmission device; and
In the second wireless transmission device, encrypting and transmitting the second wireless unit identification information using the second identifier as a key;
In the second wireless transmission device, decrypting the received first wireless unit identification information using the first identifier as a key, and extracting the first wireless unit identification information;
A mutual authentication program for causing the first and second nonvolatile storage units to store the extracted second and first wireless unit identification information, respectively. The step of writing the second and first identifiers to the first and second nonvolatile storage units, respectively,
Writing first and second identifiers to the first and second recording media respectively attached to the first and second wireless transmission devices;
Exchanging the first and second recording media between the first and second wireless transmission devices;
Reading and temporarily storing the second and first identifiers from the second and first recording media newly attached to each of the first and second wireless transmission devices. The mutual authentication program according to claim 5.

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