Communication device, communication system, and communication method

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a communication device corresponding to a plurality of different communication methods, a communication system including the communication device, and a communication method in the communication system.

【0002】

[Conventional technology]

Conventionally, when data communication is performed between electronic devices such as personal computers, PDAs (Personal Digital Assistants), and mobile phones, a method of connecting each other's electronic devices with a cable has been used. However, the method using a cable is inconvenient because it takes time and effort to connect the cable to an electronic device and the cable must be carried. Therefore, recently, wireless communication technology has come to be used for data communication between a plurality of electronic devices.

【0003】

In particular, in recent years, in order to improve the convenience of electronic devices, a plurality of highly compatible wireless communication standards have been established. If a communication device conforming to these communication standards is used, data communication with various electronic devices can be easily performed.

【0004】

[Problems to be Solved by the Invention]

However, when data communication is performed using wireless communication technology, it is necessary to pay attention to data leakage. In particular, when conforming to communication standards that enable communication with various devices, it was necessary to be careful not to accidentally receive data by other unrelated devices. As described above, in the data communication using the wireless communication technology, it has been an issue to improve the reliability in security.

【0005】

An object of the present invention is to improve security reliability without impairing the convenience of wireless communication when data is transmitted and received by wireless communication between a plurality of electronic devices.

【0006】

[Means for solving problems]

The present invention has the following features in order to solve such a problem. In the explanation of the means shown below, the configuration corresponding to the embodiment is shown as an example in parentheses. The reference numerals and the like are drawing reference codes and the like described later.

【0007】

The communication device (2) of the invention according to claim 1 uses a first communication means for transmitting and receiving radio signals (for example, the wireless communication unit 24 shown in FIG. 1) and a communication method different from the first communication means. It has a second communication means for transmitting and receiving signals (for example, the infrared communication unit 26 shown in FIG. 1) and a key information holding means for holding encryption key information (for example, the primitive encryption information storage area 101 shown in FIG. 2). The key information transmission control means (for example, the process shown in FIG. 3A) for transmitting the memory 22) and the encrypted key information held by the key information holding means to another communication device by the second communication means. The communication control means (for example, the process shown in FIG. 5) that encrypts the information based on the encryption key information held by the CPU 21) and the key information holding means and causes the first communication means to transmit the information. It is characterized by having a CPU 21) to perform.

【0008】

According to the invention according to claim 1, a first communication means for transmitting and receiving a radio signal and a second communication means for transmitting and receiving a signal by a communication method different from the first communication means are provided, and key information is provided. The encryption key information is held by the holding means, and the encrypted key information held by the key information holding means is transmitted to another communication device by the second communication means under the control of the key information transmission control means. The information transmitted by this communication device is transmitted by the first communication means after encrypting the information based on the encryption key information held in the key information holding means by the control of the communication control means. The encryption key information transmitted by the second communication means can be received only by the communication device that has received the encryption key information. As a result, security reliability can be ensured for wireless communication by the first communication means. In particular, when the wireless communication by the first communication means conforms to the wireless communication method whose specifications and standards are open to the public or widely used and compatibility is maintained, such as the Bluetooth standard, for example. It cannot be denied that information may be received by an unrelated communication device. However, by applying the present invention, the communication partner can be limited to the communication device that has received the encryption key information transmitted by the second communication means. Therefore, the confidentiality of information can be maintained and the reliability of security can be ensured without impairing the convenience of wireless communication, such as the positional relationship with the device of the communication partner being relatively free.

【0009】

The invention according to claim 2 refers to an external communication device according to claim 1, which does not hold the same encryption key information as the encryption key information held by the key information holding means. The first communication means is further provided with a communication refusal means (for example, a CPU 21 that performs the process shown in step S45 of FIG. 5) that rejects transmission / reception of a radio signal by the first communication means.

【0010】

According to the invention described in claim 2, for an external communication device that does not hold the same encryption key information as the encryption key information held in the key information holding means, the communication refusal means is used for the first method. Since the transmission / reception of the radio signal by the communication means of the above is rejected, the communication device to be the communication partner can be strictly limited, and the confidentiality of the information can be more reliably maintained.

【0011】

The invention according to claim 3 is the communication device according to claim 1 or 2, wherein the first communication means transmits / receives a wireless signal by a communication method conforming to the Bluetooth standard, and the second communication means. The communication means of the above is characterized in that a wireless signal is transmitted and received by a communication method using an infrared signal.

【0012】

According to the invention of claim 3, the first communication means transmits and receives a wireless signal by a communication method conforming to the Bluetooth (Bluetooth) standard, and the second communication means is a communication method using an infrared signal. Since wireless signals are transmitted and received by Bluetooth, the specifications are widely disclosed and it is highly convenient, but it is possible to ensure the confidentiality of information in the wireless communication of the Bluetooth (Bluetooth) standard, which is difficult to reliably conceal information. In particular, since a communication method using an infrared signal is used as the second communication means, it is possible to reduce the size, weight, cost, and power consumption of the second communication means, which is easily realized. .. Further, in the communication method using an infrared signal, the communication devices need to be close to each other and face each other within a predetermined solid angle, so that the confidentiality of information can be further enhanced.

【0013】

The invention according to claim 4 is a communication system (1) including a transmitting side device (for example, the communication device 2 shown in FIG. 1) and a receiving side device (for example, the communication device 3 shown in FIG. 1). The transmitting side device transmits / receives a signal by a first communication means for transmitting / receiving a wireless signal (for example, the wireless communication unit 24 shown in FIG. 1) and a communication method different from the first communication means. A communication means (for example, the infrared communication unit 26 shown in FIG. 1), a key information holding means for holding the encryption key information (for example, a memory 22 having a primitive encryption information storage area 101 shown in FIG. 2), and the key. The key information transmission control means (for example, the CPU 21 that performs the process shown in FIG. 3A) for transmitting the encrypted key information held by the information holding means to the receiving side device by the second communication means, and the above. A communication control means (for example, a CPU 21 that performs the process shown in FIG. 5) that encrypts information based on the encryption key information held in the key information holding means and transmits the information to the receiving device by the first communication means. ), And the receiving side device receives the encryption key information transmitted by the second communication means included in the transmitting side device (for example, the infrared communication unit 36 shown in FIG. 1 and the infrared communication unit 36). The CPU 31) that performs the processing shown in FIG. 3 (b), the receiving key information holding means (for example, the memory 32 shown in FIG. 1) that holds the encrypted key information received by the key information receiving means, and the transmitting side. It is characterized by including an encrypted information receiving means (for example, a wireless communication unit 34 shown in FIG. 1) for receiving information transmitted by the first communication means included in the device.

【0014】

According to the invention of claim 4, the communication system includes a transmitting side device and a receiving side device, and the transmitting side device is a first communication means for transmitting and receiving a radio signal and the first communication. It is equipped with a second communication means that transmits and receives signals by a communication method different from the means, holds the encrypted key information by the key information holding means, and transmits the encrypted key information held by the key information holding means. The control means transmits the information to the receiving device by the second communication means, and the control of the communication control means encrypts the information based on the encryption key information held in the key information holding means. It is transmitted to the receiving device by the communication means, and the receiving device receives the encrypted key information transmitted by the second communication means of the transmitting device by the key information receiving means and received by the key information receiving means. The encryption key information is held by the receiving key information holding means, and the information transmitted by the first communication means included in the transmitting side device is received by the encrypted information receiving means.

【0015】

The invention according to claim 8 transmits and receives a signal by a first communication means for transmitting and receiving a wireless signal (for example, the wireless communication unit 24 shown in FIG. 1) and a communication method different from the first communication means. A transmitting side device (for example, the communication device 2 shown in FIG. 1) having a second communication means (for example, the infrared communication unit 26 shown in FIG. 1) and a receiving side device (for example, the communication device 3 shown in FIG. 1). A communication method in a communication system (1) comprising the above, wherein the transmitting side device transmits encryption key information to the receiving side device by the second communication means, and the receiving side device comprises. , The step of receiving and storing the encryption key information transmitted by the second communication means of the transmitting side device, and the transmitting side device encrypting the information based on the encryption key information. It is characterized by including a step of transmitting to the receiving side device by the first communication means.

【0016】

Therefore, the information transmitted by the transmitting side device can be received only by the receiving side device. As a result, security reliability can be ensured for wireless communication in the communication system using the first communication means included in the transmitting side device. In particular, when the wireless communication by the first communication means conforms to the wireless communication method whose specifications and standards are open to the public or widely used and compatibility is maintained, such as the Bluetooth standard, for example. It cannot be denied that it may be received by an unrelated communication device. However, by applying the present invention, the communication partner can be limited to the receiving device that holds the encryption key information transmitted by the second communication means. Therefore, the confidentiality of information can be maintained and the reliability of security can be ensured without impairing the convenience of wireless communication such as the positional relationship between the devices being relatively free.

【0017】

The invention according to claim 5 is the communication system according to claim 4, wherein the transmitting side device has the same encryption key information as the encryption key information held in the key information holding means, and the receiving side device has the same encryption key information. Further provided is a communication refusal means (for example, a CPU 21 that performs the process shown in step S45 of FIG. 5) that rejects transmission / reception of a radio signal by the first communication means when it is not held by the received key information holding means. It is characterized by.

【0018】

According to the invention of claim 5, in the transmitting side device, the same encryption key information as the encryption key information held in the key information holding means is held in the receiving key information holding means of the receiving side device. If not, the communication refusal means rejects the transmission and reception of the radio signal by the first communication means, so that the communication device to be the communication partner can be more strictly limited and the confidentiality of the information can be more reliably maintained. ..

【0019】

According to the invention of claim 6, in the communication system according to claim 4 or 5, the first communication means included in the transmitting side device and the encrypted information receiving means included in the receiving side device are Bluetooth (Bluetooth). A wireless signal is transmitted and received by a communication method conforming to a standard, and the second communication means possessed by the transmitting side device and the key information receiving means possessed by the receiving side device communicate with each other using an infrared signal. It is characterized by transmitting and receiving wireless signals by a method.

【0020】

According to the invention of claim 6, the first communication means of the transmitting side device and the encrypted information receiving means of the receiving side device transmit and receive wireless signals by a communication method conforming to the Bluetooth (Bluetooth) standard. The second communication means of the transmitting side device and the key information receiving means of the receiving side device transmit and receive wireless signals by a communication method using an infrared signal, so that the specifications are widely disclosed. Information confidentiality can be ensured in Bluetooth (Bluetooth) standard wireless communication, which is highly convenient but difficult to reliably conceal information. In particular, since the second communication means and the key information receiving means use a communication method using an infrared signal, the second communication means and the key information receiving means are miniaturized, lightened, cost-reduced, and power-saving. Is possible and easily feasible. Further, in the communication method using an infrared signal, the transmitting side device and the receiving side device need to be close to each other and face each other within a predetermined solid angle, so that the confidentiality of information can be further improved.

【0021】

The invention according to claim 7 is the communication system according to any one of claims 4 to 6, wherein the key information transmission control means included in the transmitting side device encrypts the encrypted key information and performs the second communication. It is characterized in that it is transmitted by means.

【0022】

According to the invention of claim 7, since the key information transmission control means possessed by the transmitting side device encrypts the encrypted key information and transmits the encrypted key information by the second communication means, the information at the time of transmitting the encrypted key information. Leakage can be prevented more reliably. As a result, security reliability can be further enhanced.

【0023】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

【0024】

[First Embodiment] FIG. 1 is a block diagram showing a configuration of a communication system 1 as a first embodiment to which the present invention is applied. As shown in the figure, the communication system 1 is composed of a communication device 2 and a communication device 3 capable of communicating with each other. A wireless communication link A using radio waves and an infrared communication link B using infrared rays are formed between the communication device 2 and the communication device 3.

【0025】

The communication device 2 and the communication device 3 shown in FIG. 1 are both communication devices having the same configuration, but in the first embodiment, the communication device 2 is the device on the access request side and the communication device 3. Will be described as a device on the access receiving side.

【0026】

The communication device 2 includes a CPU (Central Processing Unit) 21, a memory 22, an input unit 23, a wireless communication unit 24, an antenna 25, an infrared communication unit 26, an infrared light receiving / emitting unit 27, and an interface unit 28. To.

【0027】

The CPU 21 reads and executes the system program stored in the memory 22 according to the instruction operation in the input unit 23, and drives and controls each unit of the communication device 2. Specifically, the CPU 21 controls the wireless communication unit 24 according to the program in the memory 22 and establishes the wireless communication link A with the communication device 3. Subsequently, the CPU 21 establishes the infrared communication link B by the infrared communication unit 26 and the infrared light receiving / receiving unit 27. Then, the CPU 21 transmits various information related to encryption stored in the memory 22 to the communication device 3 via the infrared communication link B.

【0028】

After that, the CPU 21 receives the information transmitted from the communication device 3 via the infrared communication link B, confirms the content of the information, and disconnects the wireless communication link A and the infrared communication link B with the communication device 3. To do.

【0029】

Further, the CPU 21 controls the wireless communication unit 24 according to the instruction input from the input unit 23, and outputs a wireless signal for scanning the communication device existing in the vicinity of the communication device 2 from the antenna 25. When a communication device that can be connected via the wireless communication line is detected by this scanning operation, the wireless communication unit 24 receives and analyzes the information transmitted from the detected communication device.

【0030】

Then, the received information is collated with the primitive encrypted information stored in the memory 22, and if they match, the connection is permitted and wireless communication with the detected communication device is started. If the received information does not match the primitive encrypted information, communication with the communication device is refused.

【0031】

The memory 22 is configured to include a non-volatile storage element such as an EEPROM or a flash memory. The memory 22 stores programs such as system programs executed by the CPU 21 and data and the like related to these programs. Further, the memory 22 temporarily holds the data processed by the CPU 21 and the data input from the input unit 23.

【0032】

Here, the data stored in the memory 22 will be described. FIG. 2 is a diagram schematically showing the configuration inside the memory 22. In the memory 22, in addition to the storage area (not shown) for storing the various programs, the primitive encryption information storage area 101 and the transfer specification information storage area 102 are provided as shown in FIG.

【0033】

The primitive encryption information storage area 101 contains an encryption key information used as a "key" for encryption and a history of transmitting the encryption key information to other electronic devices. Management information is stored. Various types of information stored in the primitive encryption information storage area 101 are collectively referred to as primitive encryption information.

【0034】

The primitive encryption information stored in the primitive encryption information storage area 101 may be stored in the primitive encryption information storage area 101 in advance, or may be input at any time by the operation of the input unit 23. You may.

【0035】

Further, in the transfer specification information storage area 102, various information such as product information, unique function information, user information, serial number, etc. of the communication device 2 is stored. Various types of information stored in the transfer specification information storage area 102 are collectively referred to as transfer specification information. The information stored in the transfer specification information storage area 102 may be stored in the memory 22 in advance, may be input by an operation of the input unit 23, or may be input to the interface unit 28. It may be input from the connected electronic device 4.

【0036】

The input unit 23 includes input devices such as a plurality of keys to which information that can be input is assigned, and generates an operation signal corresponding to the operation content and outputs the operation signal to the CPU 21.

【0037】

The wireless communication unit 24 has a built-in encoder, decoder, RF, amplifier, etc., converts a signal input from the CPU 21 to generate a wireless signal, and transmits the wireless signal to the communication device 3 via the antenna 25. Further, the wireless communication unit 24 receives the wireless signal transmitted from the communication device 3 by the antenna 25, converts the received wireless signal, and outputs the obtained signal to the CPU 21.

【0038】

Here, as the wireless communication unit 24, for example, a wireless communication unit conforming to the Bluetooth (Bluetooth) standard can be mentioned. The Bluetooth standard is a wireless communication standard established by the Bluetooth SIG (Special Interest Group) and a promoter composed of a plurality of businesses that manufacture communication devices, electronic devices, software, and the like. The Bluetooth standard uses wireless signals with a frequency in the 2.4 GHz (gigahertz) band to perform wireless communication between multiple electronic devices within approximately several meters.

【0039】

Electronic devices equipped with a wireless communication unit conforming to the Bluetooth standard form a group called piconet with each other. Then, it is possible to communicate with each other between electronic devices belonging to the same piconet. Many electronic devices can belong to the same piconet at the same time. It is also possible for one communication device to belong to multiple piconets at the same time. For this reason, it is attracting attention as a communication method for connecting various devices such as a portable telephone, a personal computer, a handheld computer called a PDA (Personal Digital Assistant), a printer, and a music player to each other. Hereinafter, the wireless communication unit 24 is a communication unit conforming to the above Bluetooth standard, and wireless communication (wireless communication via the wireless communication link A) executed using the wireless communication unit 24 and the antenna 25 is based on the Bluetooth standard. It will be described as being performed by the radio wave of the 2.4 GHz band according to the above.

【0040】

The infrared communication unit 26 has a built-in encoder, decoder, and the like, and is connected to the infrared light receiving / receiving unit 27. The infrared communication unit 26 converts the signal input from the CPU 21 and outputs it to the infrared light receiving / receiving unit 27. The infrared light receiving / emitting unit 27 has a built-in LED (Light Emitting Diode), a photo sensor, etc., and emits the built-in LED based on the signal input from the infrared communication unit 26, and directs the built-in LED to the communication device 3 as an infrared signal. Output.

【0041】

Further, when the infrared light receiving / emitting unit 27 receives infrared light from the communication device 3 by the built-in photo sensor, the infrared light receiving / emitting unit 27 converts the light receiving pattern into a predetermined signal and outputs it to the infrared communication unit 26. Further, the infrared communication unit 26 converts the signal input from the infrared light receiving / emitting unit 27 and outputs the signal to the CPU 21.

【0042】

The interface unit 28 is an interface for connecting the communication device 2 and an external electronic device of the communication device 2, and includes a connector and the like. Here, examples of the electronic device 5 connected to the interface unit 28 include, but are not limited to, a portable telephone, a personal computer, a PDA, and the like. Further, the communication device 2 has a built-in secondary battery such as a lithium ion battery or a nickel-cadmium battery (not shown), a dry battery, or the like, and operates by using these batteries as a power source, but the communication device 2 does not have a built-in battery. , The configuration may be such that power is supplied to the communication device 2 via the interface unit 28.

【0043】

Further, instead of the input unit 23 included in the communication device 2, the input device provided by the device connected to the interface unit 28 may be used. In this case, the CPU 21 may operate according to the signal input from the device connected to the interface unit 28, and may not include the input unit 23.

【0044】

Next, the configuration of the communication device 3 will be described. The communication device 3 includes a CPU 31, a memory 32, an input unit 33, a wireless communication unit 34, an antenna 35, an infrared communication unit 36, an infrared light receiving / emitting unit 37, and an interface unit 38. Here, each part of the memory 32, the input unit 33, the wireless communication unit 34, the antenna 35, the infrared communication unit 36, the infrared light receiving / emitting unit 37, and the interface unit 38 has the memory 22 and the input unit 23 of the communication device 2. It has the same configuration as each part of the wireless communication unit 24, the antenna 25, the infrared communication unit 26, the infrared light receiving / emitting unit 27, and the interface unit 28, and the description thereof will be omitted.

【0045】

The CPU 31 reads and executes the system program stored in the memory 32 according to the instruction operation in the input unit 33, and drives and controls each unit of the communication device 3. Specifically, the CPU 31 controls the wireless communication unit 34 according to the program in the memory 32, and establishes the wireless communication link A with the communication device 2.

【0046】

Subsequently, the CPU 31 establishes the infrared communication link B by the infrared communication unit 36 and the infrared light receiving / receiving unit 37. Then, the CPU 31 receives the infrared signal emitted from the infrared receiving / emitting unit 27 of the communication device 2 by the infrared receiving / emitting unit 37, and receives various information related to encryption transmitted from the communication device 2.

【0047】

Here, the CPU 31 stores various information transmitted from the communication device 2 in the memory 32, and transmits the information to the communication device 2 via the infrared communication unit 36 and the infrared light receiving / emitting unit 37. Then, when the radio signal output from the antenna 25 of the communication device 2 is received and the received signal requests the disconnection of the wireless communication link A and the infrared communication link B, the wireless communication with the communication device 2 is performed. Disconnect communication link A and infrared communication link B.

【0048】

Next, the operation of this embodiment will be described. FIG. 3 is a flowchart showing the operation of the communication system 1 in the first embodiment. FIG. 3A shows the operation of the device on the access request side, that is, the communication device 2, and FIG. 3B shows the operation of the device on the access reception side, that is, the communication device 3. In the figure, the signal indicated by the solid line arrow is a wireless signal conforming to the above Bluetooth standard transmitted / received via the wireless communication link A (Fig. 1), and the signal indicated by the broken line arrow is the infrared communication link B (Fig. 1). It is an infrared signal transmitted and received via 1).

【0049】

First, as shown in FIG. 3A, the CPU 21 starts operation according to an instruction input from the input unit 23, generates a connection request signal for connecting to the communication device 3, and is generated by the wireless communication unit 24. It is transmitted to the communication device 3 (step S11).

【0050】

The CPU 31 starts operation by inputting an instruction from the input unit 33, and shifts to a state in which the wireless communication unit 34 can receive the wireless signal transmitted from the communication device 2. Then, when the connection request transmitted from the wireless communication unit 24 is received by the wireless communication unit 34 (step S21), a connection confirmation signal for confirming the connection is generated and transmitted by the wireless communication unit 34 (step S22).

【0051】

When the wireless communication unit 24 receives the connection confirmation signal transmitted from the wireless communication unit 34 under the control of the CPU 31, the CPU 21 receives the transfer specification information stored in the transfer specification information storage area 102 of the memory 22 (step S12). It is read out and transmitted as an infrared signal to the communication device 3 by the infrared communication unit 26 and the infrared light receiving / receiving unit 27 (step S13).

【0052】

When the CPU 31 receives the transfer specification information transmitted as an infrared signal by the infrared communication unit 26 of the communication device 2 by the infrared communication unit 36 (step S23), the CPU 31 is stored in the transfer specification information storage area 102 of the memory 32. The transfer specification information is read out and transmitted by the infrared communication unit 36 (step S24).

【0053】

When the CPU 21 receives the transfer specification information transmitted from the communication device 3 by the infrared communication unit 26 (step S14), the CPU 21 reads the primitive encryption information stored in the primitive encryption information storage area 101 in the memory 22. , The infrared communication unit 26 transmits the information to the communication device 3 (step S15).

【0054】

When the CPU 31 receives the primitive encryption information transmitted from the communication device 2 (step S25), the CPU 31 stores the received primitive encryption information in the primitive encryption information storage area 101 in the memory 32 (step S26). Here, the primitive encryption information previously stored in the primitive encryption information storage area 101 of the memory 32 may be overwritten by the newly received primitive encryption information, or may be newly received. It may be stored in an area different from the received primitive encrypted information.

【0055】

Subsequently, the CPU 31 receives in step S25 and transmits the primitive encryption information stored in the primitive encryption information storage area 101 in the memory 32 to the communication device 2 by the infrared communication unit 36 (step S27).

【0056】

When the CPU 21 receives the primitive encryption information transmitted from the communication device 3 (step S16), the CPU 21 receives the received primitive encryption information and the primitive encryption information stored in the primitive encryption information storage area 101 of the memory 22. And confirm that they match (step S17). That is, by confirming that the primitive encryption information transmitted to the communication device 3 in step S15 and the primitive encryption information transmitted from the communication device 3 match, the primitive encryption in steps S15, S16, S25, and S26 Confirm that the transmission and reception of the encryption information was executed without any problem.

【0057】

Then, the CPU 21 generates a disconnection request signal requesting the disconnection of the communication, and causes the wireless communication unit 24 to transmit the disconnection request signal to the communication device 3 (step S18). When the CPU 31 receives the disconnection request signal transmitted from the communication device 2 by the wireless communication unit 34 (step S28), the CPU 31 generates a disconnection confirmation signal confirming the reception of the disconnection request, and the wireless communication unit 34 sends the disconnection request signal to the communication device 2. It is transmitted (step S29), and this process is terminated.

【0058】

Further, when the CPU 21 receives the disconnection confirmation signal transmitted from the communication device 3 by the wireless communication unit 24 (step S19), the CPU 21 ends this process.

【0059】

By the process shown in FIG. 3 above, the memory 22 of the communication device 2 and the memory 32 of the communication device 3 have previously stored the primitive encryption information stored in the primitive encryption information storage area 101 in the memory 22. It will be in the stored state.

【0060】

In the process shown in FIG. 3, the transfer specification information and the primitive encrypted information are transmitted and received via the infrared communication link B (FIG. 1). In general, when performing wireless communication using an infrared signal, it is necessary that the electronic devices to be communicated are close to each other and the infrared receiving and emitting units of the electronic devices are opposed to each other. In particular, the infrared receiving and emitting parts of each other's electronic devices must face each other so as to fit in a relatively narrow solid angle, and the possibility of being intercepted by unrelated electronic devices is low, and security concerns are small. It is a thing. However, by applying the encryption described below, the security reliability in the communication via the infrared communication link B can be further ensured.

【0061】

FIG. 4A illustrates a hierarchical model showing a protocol configuration in infrared communication when performing encryption. Further, FIG. 4 (b) schematically shows the configuration of the data unit in infrared communication.

【0062】

Generally, in infrared communication, if compatibility is maintained in the data link layer, link management layer, and transport layer, protocol compatibility is maintained even if the service data unit in the higher layer is encrypted. be able to. Therefore, as shown in FIG. 4A, a security data exchange protocol in which a layer higher than the transport layer is used as an encryption layer and the upper layer is used as the above-mentioned transfer specification information and primitive encryption information. If it is a layer, it is possible to maintain the confidentiality of the transferred information while maintaining the protocol compatibility.

【0063】

Specifically, as shown in Figure 4 (b), the service data unit following the LAP (Data Link Layer), LMP (Link Management Layer), and TP (Transport Layer) protocol data units is encrypted. Just do it. Therefore, by encrypting and decrypting the signal transmitted and received via the infrared communication link B in both the communication device 2 and the communication device 3, the transfer specification information and the primitive encryption transmitted and received in the process shown in FIG. The confidentiality of information can be made more reliable.

【0064】

FIG. 5 is a flowchart showing the operation of the communication device 2 after the processing shown in FIG. 3 is executed. In the process shown in FIG. 5, the communication device 2 operates as a Master device defined by the Bluetooth standard. The wireless signal transmitted and received in the process shown in FIG. 5 is a 2.4 GHz band wireless signal conforming to the Bluetooth standard.

【0065】

First, the CPU 21 starts the operation according to the instruction input from the input unit 23, controls the wireless communication unit 24 to execute the Page Scan operation, and detects a communication device capable of communicating according to the Bluetooth standard (step). S41).

【0066】

Then, when a connectable communication device is detected, the information transmitted from the detected device is received in response to the Page Scan operation by the CPU 21 (step S42), and the received information and the primitive encryption information in the memory 22 are received. The collation with the primitive encrypted information stored in the storage area 101 is performed (step S43).

【0067】

Here, when the communication device 2 detects the communication device 3, the communication device 3 already holds the primitive encryption information stored in the primitive encryption information storage area 101 in the memory 22, and therefore Page Scan. The information encrypted according to the primitive encryption information is transmitted according to the operation. When a communication device unrelated to the communication device 2 and the communication device 3 is detected, a normal wireless signal is transmitted from the unrelated communication device according to the Page Scan operation. Therefore, it is possible to determine whether or not the communication device detected in step S41 is the communication device 3 by the collation in step S43.

【0068】

If, as a result of the collation in step S43, the radio signal received in step S42 is irrelevant to the primitive encrypted information (step S44; No), the CPU 21 refuses to connect to the detected communication device (step S45). ), End this process.

【0069】

Further, if the radio signal received in step S42 conforms to the primitive encryption information by the collation in step S43 (step S44; Yes), the CPU 21 stores the primitive encryption information with the detected communication device. The transmission / reception of the radio signal encrypted by the primitive encryption information in the area 101 is started (step S46). The information encrypted by the primitive encryption information stored in the primitive encryption information storage area 101 can be decrypted based on the primitive encryption information. Therefore, the CPU 21 encrypts the information transmitted by the wireless communication unit 24 and decodes the information received by the wireless communication unit 24.

【0070】

Then, the CPU 21 permits the use in the application after the negotiation with the detected communication device is completed (step S47). After that, the CPU 21 executes a process of transmitting and receiving an encrypted wireless signal in response to a request of an application program executed on the communication device 2 or the electronic device 4 connected to the interface unit 28 (step S48). , This process is terminated by inputting an instruction from the input unit 23.

【0071】

As described above, according to the first embodiment of the present invention, the wireless communication unit 24 and the antenna 25 that perform wireless communication according to the Bluetooth standard, and the infrared communication unit 26 and the infrared communication unit 26 that perform wireless communication using infrared signals. Primitive encrypted information is transferred in advance between the communication device 2 provided with the infrared light receiving / receiving unit 27 and the communication device 3 having the same configuration as the communication device 2 by infrared communication, and then transferred to the transferred primitive encrypted information. Information encrypted based on this is transmitted and received by wireless communication according to the Bluetooth standard. As a result, it is possible to perform highly convenient communication in accordance with the Bluetooth standard while maintaining high confidentiality.

【0072】

That is, when wireless communication conforming to the Bluetooth standard is used, it is possible to form a piconet and start communication simply by bringing the communication devices close to each other. Further, each communication device during communication can form a piconet with another communication device at the same time, and can perform flexible communication. Further, the communication devices forming the piconet need only be close to each other within a predetermined distance, and their positions are less likely to be constrained. On the other hand, in wireless communication conforming to the Bluetooth standard, it is difficult to transmit information only to a specific communication device, and it cannot be denied that the information may be mistakenly received by an unrelated communication device. However, according to the communication system 1 in the first embodiment, the primitive encrypted information is transferred between the communication device 2 and the communication device 3 in advance by infrared communication, so that the communication device is affected by the unrelated communication device. Primitive encrypted information is shared without any need, and information encrypted using this primitive encrypted information is transmitted and received by wireless communication conforming to the Bluetooth standard. Therefore, highly convenient wireless communication can be performed while ensuring security reliability.

【0073】

In the above embodiment, the communication device 2 and the communication device 3 perform wireless communication via a wireless communication link A conforming to the Bluetooth standard, but the present invention is not limited to this. However, it can be applied to a wireless communication system whose specifications and standards are open to the public or widely used and compatibility is maintained, and has the same effect as the above-mentioned communication system 1.

【0074】

Further, when the present invention is applied to various electronic devices such as a portable telephone, a PDA, a personal computer, a printer, and a music player, the electronic device 4 is applied to the communication device 2 and the communication device 3 as shown in FIG. Not limited to the configuration in which 5 is connected, it is of course possible to incorporate the functions of communication devices 2 and 3 into the above-mentioned various electronic devices.

【0075】

Further, in the first embodiment, the communication device 2 and the communication device 3 both include input units 23 and 33, and the processing shown in FIG. 3 is started by the instruction input in these input units 23 and 33. However, the configuration does not necessarily have to include the input units 23 and 33. Hereinafter, this case will be described as a second embodiment.

【0076】

[Second Embodiment] FIG. 6 is a block diagram showing a configuration of a communication system 10 according to a second embodiment of the present invention.

【0077】

As shown in the figure, the communication system 10 is composed of a communication device 2 and a communication device 3a. The communication system 10 has the same configuration as the communication system 1 in the first embodiment except for the memory 61 and the switch 62 included in the communication device 3a, and the common parts are designated by the same reference numerals. The explanation will be omitted.

【0078】

The switch 62 includes one or more switches, and generates an operation signal each time it is operated and outputs it to the CPU 31.

【0079】

FIG. 7 is a diagram schematically showing the internal configuration of the memory 61. As shown in the figure, a primitive encryption information storage area 103 and a transfer specification information storage area 102 are provided in the memory 61, and the transfer specification information storage area 102 contains product information, unique function information, and the like. Transfer specification information such as user information and serial number is stored. On the other hand, the primitive encryption information is not stored in advance in the primitive encryption information storage area 103.

【0080】

In the communication system 1 described in the first embodiment, in the process shown in FIG. 3, the primitive encryption information is transferred from the communication device 2 to the communication device 3 and stored in the primitive encryption information storage area 101 of the memory 22. The primitive encryption information that has been stored is stored in the primitive encryption information storage area 101 of the memory 32. In the communication system 10 according to the second embodiment, when the primitive encryption information is transferred from the communication device 2 to the communication device 3a, the transferred primitive encryption information is transferred to the primitive encryption information storage area 103 of the memory 61. It is stored. Therefore, the communication device 3a can operate in the same manner as the communication device 3.

【0081】

Further, in the communication system 1 described in the first embodiment, the process shown in FIG. 3 is started by the instruction input in the input unit 23 of the communication device 2 and the input unit 33 of the communication device 3. did. In the communication system 10 according to the second embodiment, the same processing as that shown in FIG. 3 is executed by the instruction input in the input unit 23 of the communication device 2 and the switch operation of the switch 62 of the communication device 3a. Will be done.

【0082】

That is, the communication device 3a is a device provided only with the switch 62 as an input means, but is used as a device that only performs an operation of receiving access by the communication device 2 instead of the communication device 3 in the first embodiment. It is possible. Further, since it is not used as a device on the access request side instead of the communication device 2, it is not necessary to store the primitive encryption information in advance in the primitive encryption information storage area 103 of the memory 61.

【0083】

Therefore, the communication system 10 in the second embodiment has the same effect as that in the first embodiment by using the communication device 3a having only the input switch 62. As a result, in wireless communication conforming to the Bluetooth standard, a device that functions only as a Slave device can obtain the same effect as that of the communication system 1 by simply providing a switch as an input means.

【0084】

[Effect of the invention]

According to the communication device of the invention according to claim 1, the transmitted information can be received only by the communication device that has received the encryption key information transmitted by the second communication means. As a result, security reliability can be ensured for wireless communication by the first communication means. In particular, when the wireless communication by the first communication means conforms to the wireless communication method whose specifications and standards are open to the public or widely used and compatibility is maintained, such as the Bluetooth standard, for example. It cannot be denied that it may be received by an unrelated communication device. However, by applying the present invention, the communication partner can be limited to the communication device that has received the encryption key information transmitted by the second communication means. Therefore, the confidentiality of information can be maintained and the reliability of security can be ensured without impairing the convenience of wireless communication, such as the positional relationship with the device of the communication partner being relatively free.

【0085】

According to the communication device of the invention according to claim 2, the communication refusal means is used for an external communication device that does not hold the same encryption key information as the encryption key information held in the key information holding means. Since the transmission / reception of the radio signal by the first communication means is rejected, the communication device to be communicated with can be strictly limited, and the confidentiality of information can be more reliably maintained.

【0086】

According to the communication device of the invention according to claim 3, the specifications are widely disclosed and the information is highly convenient, but the confidentiality of information is ensured in the wireless communication of the Bluetooth (Bluetooth) standard in which it is difficult to reliably conceal information. Can be done. In particular, since a communication method using an infrared signal is used as the second communication means, it is possible to reduce the size, weight, cost, and power consumption of the second communication means, which is easily realized. .. Further, in the communication method using an infrared signal, the communication devices need to be close to each other and face each other within a predetermined solid angle, so that the confidentiality of information can be further enhanced.

【0087】

According to the communication system of the invention according to claim 4 and the communication method of the invention according to claim 8, the information transmitted by the transmitting side device can be received only by the receiving side device. As a result, security reliability can be ensured for wireless communication in the communication system using the first communication means included in the transmitting side device. In particular, when the wireless communication by the first communication means conforms to the wireless communication method whose specifications and standards are open to the public or widely used and compatibility is maintained, such as the Bluetooth standard, for example. It cannot be denied that it may be received by an unrelated communication device. However, by applying the present invention, the communication partner can be limited to the receiving device that holds the encryption key information transmitted by the second communication means. Therefore, the confidentiality of information can be maintained and the reliability of security can be ensured without impairing the convenience of wireless communication such as the positional relationship between the devices being relatively free.

【0088】

According to the communication system of the invention according to claim 5, in the transmitting side device, the same encryption key information as the encryption key information held in the key information holding means is transmitted to the receiving key information holding means held in the receiving side device. If it is not retained, the communication refusal means rejects the transmission and reception of the radio signal by the first communication means, so that the communication device to be communicated with is more strictly limited and the confidentiality of the information is more reliably maintained. be able to.

【0089】

According to the communication system of the invention according to claim 6, the specifications are widely disclosed and the information is highly convenient, but the confidentiality of information is ensured in the wireless communication of the Bluetooth (Bluetooth) standard in which it is difficult to reliably conceal information. Can be done. In particular, since the second communication means and the key information receiving means use a communication method using an infrared signal, the second communication means and the key information receiving means are miniaturized, lightened, cost-reduced, and power-saving. Is possible and easily feasible. Further, in the communication method using an infrared signal, the transmitting side device and the receiving side device need to be close to each other and face each other within a predetermined solid angle, so that the confidentiality of information can be further improved.

【0090】

According to the communication system of the invention according to claim 7, the key information transmission control means included in the transmitting side device encrypts the encrypted key information and transmits the encrypted key information by the second communication means, so that the encrypted key information is transmitted. Leakage of information can be prevented more reliably. As a result, security reliability can be further enhanced.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram which shows the structure of the communication system 1 in the 1st Embodiment to which this invention is applied.

[Figure 2]

It is a figure which shows typically the internal structure of the memory 22, 32 of FIG.

[Fig. 3]

It is a flowchart which shows the operation of the communication system 1 of FIG. 1, (a) shows the operation of a communication device 2, and (b) shows the operation of a communication device 3.

[Fig. 4]

It is explanatory drawing which shows the protocol structure when the process shown in FIG. 3 is encrypted, (a) shows the hierarchical model which shows the protocol structure in infrared communication at the time of performing encryption, and (b) is an infrared ray. The configuration of the data unit in communication is schematically shown.

[Fig. 5]

It is a flowchart which shows the operation when the communication device 2 of FIG. 1 performs wireless communication conforming to the Bluetooth standard.

[Fig. 6]

It is a block diagram which shows the structure of the communication system 10 in the 2nd Embodiment to which this invention is applied.

[Fig. 7]

It is a figure which shows typically the internal structure of the memory 61 shown in FIG.

[Explanation of symbols]

1,10 communication system A few communication devices 21,31 CPU 22,32 memory 23,33 Input section 24,34 Wireless communication unit 25,35 antenna 26,36 Infrared communication unit 27,37 Infrared light receiving / emitting unit 28,38 Interface section 61 memory 62 switch 101,103 Primitive encryption information storage area 102 Transfer specification information storage area