JP2002016594A - Wireless communication device and key length control method for encryption / decryption processing applied to the device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To automatically set an upper limit value of the length of a key used for encryption / decryption processing in a wireless communication device to a value corresponding to an area where the wireless communication device is used. A position information detecting unit receives an electric wave from a GPS satellite by an antenna and inputs the electric wave to a GPS receiving unit. The GPS receiving unit 34 despreads and demodulates the spectrum-spread signal from the GPS satellite, and sends the demodulated signal to the positioning unit 35. The positioning unit 35 extracts information on the position when the wireless communication device is used from the demodulated signal and outputs the information to the CPU 37 of the specification control unit 32.
Upon receiving the position information sent from the position information detecting unit 31, the CPU 37 uses the table or the like in the memory 36 to perform encryption / decryption suitable for the current position of the wireless communication device based on the position information. A maximum key length for processing is obtained, and control is performed such that the key length for encryption / decryption processing in the communication unit 21 is limited by the maximum key length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radio communication apparatus and a key length control method for encryption / decryption processing applied to the apparatus.

[0002]

2. Description of the Related Art The maximum key length (key length upper limit value) of a key used for encryption / decryption processing in a wireless communication device is regulated by a competent supervisory organization of a country from which the wireless communication device is exported. Must be determined for each export destination based on the regulations.

The length of a key used for the encryption / decryption processing is determined by a predetermined number of bits (in the case of Japan, 56 bits).
If the wireless communication device is used, the area in which the wireless communication device is used is determined according to the regulations of the jurisdiction of the exporting country, and whether or not the wireless communication device can be exported is determined.

[0004]

However, even if the wireless communication device is exported via a regular route, it is brought out of the area originally assumed by the terminal user, and the jurisdiction overseeing organization of the country of the export source establishes it. It may be used out of the specified rules. In addition, in this case, there is a possibility that a problem may occur in the export control of strategic goods.

[0005] Therefore, even when the wireless communication device is brought out of the area originally assumed by the end user, the wireless communication device is used so as not to deviate from the regulations set by the jurisdiction overseeing organization of the country of the export source. It is necessary to take measures.

The present invention has been made in view of the above circumstances, and sets the upper limit of the length of a key used for encryption / decryption processing in a wireless communication device to a value corresponding to an area where the wireless communication device is used. An object of the present invention is to provide a wireless communication device that can be automatically set and a key length control method for encryption / decryption processing applied to the device.

[0007]

According to the present invention, there is provided a wireless communication apparatus for storing information defining a maximum key length of an encryption / decryption key for each region when the wireless communication apparatus is used. Means for detecting a position of the wireless communication device from a signal transmitted from a GPS satellite, means for deriving a maximum key length corresponding to an area to which the detected position belongs according to information stored in the storage means, Means for controlling such that the key length for encryption / decryption processing in the wireless communication device is limited by the maximum key length.

[0008] Further, a wireless communication apparatus according to the present invention comprises: means for storing information defining a maximum key length of an encryption / decryption key for each region when the wireless communication apparatus is used; Means for detecting the position of the wireless communication device from a signal transmitted from the base station, means for deriving a maximum key length corresponding to an area to which the detected position belongs according to information stored in the storage means, Means for controlling such that the key length for encryption / decryption processing in the wireless communication apparatus is limited by the maximum key length.

In each of the above wireless communication devices, the storage means stores a table in which a maximum key length of an encryption / decryption key is determined for each of an export-licensed country and an export-unlicensed country. It may be.

[0010] In each of the above wireless communication devices, the detecting means may detect the position in accordance with an operation command given when power is turned on.

In each of the above wireless communication devices, the detecting means may detect the position according to an operation command given by a switch operation.

[0012] The key length control method for encryption / decryption processing applied to the wireless communication apparatus according to the present invention is characterized in that the maximum key length of the encryption / decryption key when the wireless communication apparatus is used is set to a local area. The information determined for each is stored in advance in the wireless communication device, the position of the wireless communication device is detected from a signal transmitted from a GPS satellite, and the maximum key length corresponding to the area to which the detected position belongs is determined. And deriving according to the stored information, and controlling the key length for encryption / decryption processing in the wireless communication device to be limited by the derived maximum key length.

Further, the key length control method for encryption / decryption processing applied to the wireless communication device according to the present invention is characterized in that the maximum key length of the encryption / decryption key when the wireless communication device is used. Is stored in the wireless communication device in advance, the position of the wireless communication device is detected from a signal transmitted from the base station of the cellular phone, and the information corresponds to the region to which the detected position belongs. A maximum key length to be obtained is derived in accordance with the stored information, and control is performed such that a key length for encryption / decryption processing in the wireless communication apparatus is limited by the derived maximum key length.

In each of the encryption / decryption key length control methods described above, the stored information is divided into an export-licensable country and a license-exempt country, and the maximum of the encryption / decryption key is divided into two. It may include a table that defines the key length.

In each of the above-described key length control methods for encryption / decryption processing, the position detection may be executed in accordance with an operation command given when power is turned on.

In each of the above-described key length control methods for encryption / decryption processing, the position detection may be performed according to an operation command given by a switch operation.

Further, according to the present invention, a wireless communication apparatus having a wireless communication function for performing wireless communication with another device includes a key used for encrypting / decrypting communication information when using the wireless communication function. Storage means for storing the maximum key length for each area, detection means for detecting the location area of the wireless communication device, and extracting the maximum key length corresponding to the area detected by the detection means from the storage means. Means for limiting the key to not more than the extracted maximum key length.

Further, according to the present invention, a wireless communication apparatus having a wireless communication function for performing wireless communication with another device stores a maximum key length for each region of a key used for encryption / decryption of information. Storing means, a detecting means for detecting a location area of the wireless communication device, and extracting a maximum key length corresponding to the area detected by the detecting means from the storing means, It is characterized by comprising means for setting the key length to be less than the key length, and communication means for performing wireless communication by encrypting / decrypting information using the key set by the setting means.

Further, according to the present invention, a wireless communication apparatus having a wireless communication function for performing wireless communication with another device is provided with a key used for encrypting / decrypting communication information when using the wireless communication function. Storage means for storing the maximum key length for each area, detection means for detecting the location area of the wireless communication device, acquisition means for acquiring information on the maximum key length from a partner device of wireless communication, and the acquisition means Means for comparing the maximum key length of the partner device obtained by the above and the maximum key length corresponding to the area detected by the detection means, and limiting the key to a smaller maximum key length or less. It is characterized by.

A key length control method for encryption / decryption processing applied to a wireless communication apparatus having a wireless communication function of performing wireless communication with another device according to the present invention has a wireless communication function. A maximum key length for each region of a key used for encryption / decryption of communication information when used is stored, a location area of the wireless communication apparatus is detected, and a maximum key length corresponding to the detected area is detected. Is extracted from the stored maximum key length for each area, and the key is limited to not more than the extracted maximum key length.

Further, according to the key length control method for encryption / decryption processing applied to a wireless communication apparatus having a wireless communication function of performing wireless communication with another device according to the present invention, there is provided a method for encrypting information. / The maximum key length for each area of the key used for decryption is stored, the location area of the wireless communication device is detected, and the maximum key length corresponding to the detected area is stored in the stored area. Extracting from another maximum key length, limiting and setting the key to be equal to or less than the extracted maximum key length, and performing wireless communication by encrypting / decrypting information using the set key. I do.

A key length control method for encryption / decryption processing applied to a wireless communication apparatus having a wireless communication function of performing wireless communication with another device according to the present invention has a wireless communication function. The maximum key length for each region of a key used for encryption / decryption of communication information at the time of use is stored, the location area of the wireless communication device is detected, and information on the maximum key length is received from a partner device of wireless communication. And comparing the obtained maximum key length of the partner device with the maximum key length corresponding to the detected area, and limiting the key to a smaller maximum key length or less.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 shows the overall schematic configuration of a communication system to which the present invention is applied. As shown in FIG. 1, for example, a wireless communication device 12 is mounted on a personal computer (hereinafter abbreviated as a personal computer) 11 and a wireless communication device 14 is mounted on a portable telephone 13. Then, wireless communication is performed between the personal computer 11 and the portable telephone 13 via the wireless communication devices 12 and 14. Further, the portable telephone 13 has a function of performing direct wireless communication with the base station 15.

The wireless communication devices 12 and 14 are configured as shown in FIG. The wireless communication device 12, 1 shown in FIG.
No. 4 is equipped with a Bluetooth interface, which is a short-range wireless data communication technology, and can perform wireless communication with other devices equipped with a Bluetooth interface.
The function corresponding to the Bluetooth interface is implemented in the transmission / reception module 22 and the CPU 37 described later.

The communication unit 21 is controlled by the CPU 37 to communicate with a communication unit of another wireless communication device. The communication unit 21 includes a transmission / reception module 22 for realizing the function of the Bluetooth interface. When performing short-range wireless data communication, the transmission / reception module 2
2 are used.

The communication unit 21 is provided with an encryption / decryption processing unit 23 for performing an encryption process or a decryption process necessary for various data processing performed inside the communication unit 21. In particular, the maximum length of a key that can be used in the encryption / decryption processing is set by a CPU 37 described later or the communication unit 21 itself. In addition, the communication unit 21 compares the maximum key length of the other party obtained by negotiation with another wireless communication device with its own maximum key length, and uses the shorter maximum key length of the two for communication. Is controlled so that the key length in the encryption / decryption processing is restricted. For example, an encryption key of data to be transmitted to another wireless communication device cannot be used if the length exceeds the maximum key length.

When the communication section 21 receives a transmission signal sent from the personal computer 11 or the portable telephone 13, the communication section 21 modulates the signal with a predetermined carrier frequency, amplifies the signal, and then converts the radio signal from the antenna 24 to another signal. Send to device. When the communication unit 21 receives the wireless signal transmitted thereto by the antenna 24, the communication unit 21 amplifies the signal, demodulates the signal at a predetermined carrier frequency, and outputs the signal to the personal computer 11 or the portable telephone 13 as a reception signal. I do.

The position information detector 31 is a GPS (Global P
an antenna 33 for receiving radio waves from a satellite, a GPS receiving unit 34, and a positioning unit 35. For example, each time the wireless communication device is powered on, the specification control unit 32
Is activated by a start command from the CPU 37.

The position information detecting section 31 receives a radio wave from a GPS satellite with an antenna 33 and inputs the radio wave to a GPS receiving section 34. Since the signal from the GPS satellite is spread spectrum, the signal is despread in the GPS receiving unit 34 and the demodulated signal is sent to the positioning unit 35. The positioning unit 35 extracts information on the position when the wireless communication device is used from the demodulated signal, and outputs the information to the specification control unit 32. GPS
By receiving radio waves emitted from a plurality of GPS satellites (Navstar), 3
Dimension information (latitude, longitude, altitude) can be known.

The specification control unit 32 comprises a memory 36 for storing specifications of the maximum key length for encryption / decryption in each country (each region), and a CPU 37. The position information output from the position information detection unit 31 Is input to the CPU 37.

The memory 36 stores specifications (tables) in which the maximum key length for encryption / decryption of the wireless device is determined for each country. Specifically, for example, a table as shown in FIG. 3 is stored. In this example, the maximum key length of an encryption / decryption key when the device is used in a country subject to export license and the encryption / decryption when the device is used in a country not subject to export license The maximum key length of the application key is defined.

As the maximum key length corresponding to the export licensing target country, the maximum key length (for example, 128 bits) permitted by the authority at the time of export application is adopted. On the other hand, the maximum key length for countries not subject to export license is Wassenaar Arrang
A maximum key length (for example, 56 bits, which may be set to 64 bits in encryption / decryption of widely used software) according to export regulations is adopted.

As shown in FIG. 4, the memory 36 first stores the country (region) to which the position belongs from the latitude and longitude.
, And thereafter, an application program for deriving the maximum key length with reference to the table of FIG. 3 may be stored. Further, as shown in FIG.
An application program for automatically deriving either one of the maximum key length corresponding to the country subject to the license and the maximum key length corresponding to the country not subject to the license directly from the latitude and longitude may be stored. . Such an application program is executed by the CPU 37.

The CPU 37 is realized by a microprocessor, for example, and controls the entire wireless communication apparatus. The CPU 37 has a part of a function corresponding to the Bluetooth interface as described later, and this function is used when performing short-range wireless data communication.

When the CPU 37 receives the position information sent from the position information detecting section 31, it uses the table in the memory 36 or an application program to determine the current position of the wireless communication apparatus based on the position information. The maximum key length for the encryption / decryption process suitable for the country (region) to which the device belongs belongs, and control is performed such that the key length for the encryption / decryption process in the communication unit 21 is limited by the maximum key length. .

FIG. 6 is a diagram showing an outline of the layer structure of the Bluetooth interface provided in the wireless communication devices 12 and 14.

As shown in the figure, RF and baseband are layers realized as hardware, while LMP (Link Manager Protocol) and HCI (Host Con
troller Interface), L2CAP (Logical Link Control)
l and Adaptation Protocol), Service Discove (SDP)
ry Protocol) and RFCOMM are layers realized as firmware. RF, baseband, and LMP are implemented in module 22, and L2CAP, S2
The DP and the RFCOMM are mounted on the CPU 37.
The HCI is mounted on both the module 22 and the CPU 37.

The RF and baseband are R
It is realized in the form of an F transceiver LSI, a baseband signal processing LSI, or the like, and performs control related to a carrier frequency. L
The MP performs connection establishment, security, and control thereof. L2CAP performs integration, division, assembly, and the like of upper layer data and lower layer data. SDP is
Device information (device type, microprocessor,
Information about the OS, application software, etc.) is exchanged with another device equipped with a Bluetooth interface, and the currently effective service is confirmed. RFCO
The MM uses an existing serial interface (for example, RS-
232C) so that it can be used. The HCI controls the transport bus so that the transmission / reception module 22 and the CPU 37 can communicate with each other via a bus (transport bus).

Next, referring to the flowchart of FIG.
The operation in the present embodiment will be described. Position information detector 3
1 operates each time the power of the wireless communication apparatus is turned on.
Radio wave from PS satellite is received by antenna 33 and GP
It is input to the S receiver 34. The GPS receiving unit 34
The spectrum-spread signal sent from the satellite is despread and demodulated, and the demodulated signal is sent to the positioning unit 35. The positioning unit 35 extracts information on the position when the wireless communication device is used from the demodulated signal,
2 to the CPU 37. Thereby, the CPU 37
Specifies the position of the wireless communication device based on the positioning information sent from the positioning unit 35 (step A1).

Then, from the specified position, the CPU 37 uses a table or an application program in the memory 36 to apply to the country (region) to which the current position of the wireless communication device belongs, that is, the maximum key length (=
X) is obtained (step A2). This maximum key length X
Is sent from the CPU 37 to the communication unit 21 and the communication unit 2
1 is stored in a predetermined memory. At this time,
The key length used in the encryption / decryption processing of the decryption processing unit 23 is limited by the maximum key length X, and a key length exceeding X cannot be used.

The transmission / reception module 22 in the communication unit 21
In performing communication with another wireless communication device, negotiation with the communication partner is started (step A3).
The transmission / reception module 22 acquires the maximum key length (= Y) for encryption / decryption processing determined on the communication partner side from the result of the negotiation (step A).
4).

The communication unit 21 determines that the acquired maximum key length Y is
It is determined whether or not the key length is not less than the maximum key length X (step A5). If Y is not less than X, X is set as the key length upper limit value of the wireless communication device (step A6). On the other hand, if Y is not equal to or more than X, Y is set as the key length upper limit value in the wireless communication device (step A7). As described above, the smaller value of X and Y is adopted as the key length upper limit value.

The communication section 21 applies the finally adopted upper limit value to the encryption / decryption processing of the encryption / decryption processing section 23 (step A8). As a result, in the encryption / decryption processing relating to the communication with the communication partner or the like, a key length exceeding the finally adopted upper limit cannot be used.

As described above, according to the first embodiment, G
By using information from the PS satellite, the current position of the wireless communication device is determined, and encryption / decryption processing cannot be performed with a key length exceeding the maximum key length (key length upper limit value) corresponding to the area. Therefore, even if the wireless communication device is brought out of the area originally assumed by the end user, it will be used outside the provisions of the competent regulatory authority of the country of export. Can be prevented.

(Second Embodiment) Next, a second embodiment of the present invention will be described. FIG. 8 is a diagram illustrating a configuration of a wireless communication device according to the second embodiment. Elements common to those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof will be omitted. The overall schematic configuration of the communication system including the wireless communication device according to the second embodiment is the same as that shown in FIG.

The second embodiment shows an example in which information from a base station of a cellular telephone is used as the position information detecting means. That is, this second
In the second embodiment, a position information detector 41 using information from a base station of a cellular telephone is provided as shown in FIG. 8 instead of the position information detector 31 using GPS satellites in the first embodiment. I have.

The position information detecting section 41 includes an antenna 42 for receiving a radio wave from a base station of a cellular telephone, a cellular telephone receiving section 43 for demodulating a received signal, and a base station based on the signal demodulated by the cellular telephone receiving section 43. It consists of a positioning unit 44 that extracts information on the latitude and longitude of the station,
For example, each time the wireless communication device is powered on, the CPU 37
A start command is given from the controller to operate.
The information on the latitude and longitude output from the positioning unit 44 is sent to the specification control unit 32. Other configurations are the first
This is the same configuration as that of the embodiment.

In a CDMA portable mobile telephone system based on ARIB STD T53, which is one of the cellular telephones, a paging channel is used to transmit control information from a base station to a mobile station. One is a system parameter message, which includes information indicating the latitude and longitude of the base station, such as BASE LAT and BASE LONG, respectively. The latitude of the base station,
Although the longitude and the position of the communication device receiving the radio wave from the base station are strictly different, if the cell size of the base station is sufficiently small for the range where a certain specification is adopted, both are almost the same. Can be considered to be in the same position. Therefore, the position information detecting unit 41 can detect information on the latitude and longitude of the base station, and can control the maximum key length in the wireless communication device according to the information.

That is, the position information detecting section 41 receives a radio wave from the cellular base station by the antenna 42 every time the power of the radio communication apparatus is turned on, and inputs the received signal to the cellular telephone receiving section 43. The cellular telephone receiving section 43 demodulates a signal from the base station and sends it to the positioning section 44. The positioning unit 44 extracts information on the latitude and longitude of the base station from the demodulated signal and transmits the information to the CPU 37 in the specification control unit 32.

When the CPU 37 receives the position information sent from the position information detecting section 41, it uses the table in the memory 36 and an application program to determine the current position of the wireless communication apparatus based on the position information. The maximum key length for the encryption / decryption process suitable for the country (region) to which the device belongs belongs, and control is performed such that the key length for the encryption / decryption process in the communication unit 21 is limited by the maximum key length. . Note that the configuration and functions of the communication unit 21 are as described in the first embodiment.

Next, referring to the flowchart of FIG.
The operation in the present embodiment will be described. Position information detector 4
1 operates each time the power of the wireless communication apparatus is turned on, receives a radio wave from the base station of the cellular telephone by the antenna 42, and inputs it to the cellular telephone receiving unit 43. Cellular telephone receiving section 43 demodulates the received signal and sends the demodulated signal to positioning section 44. The positioning unit 44 extracts information on the position when the wireless communication device is used from the demodulated signal and outputs the information to the CPU 37 of the specification control unit 32. Thereby, the CPU 37 specifies the position of the wireless communication device based on the positioning information sent from the positioning unit 44 (Step B1).

The following steps B2 to B8 are performed in the first
Since this is the same as steps A2 to A8 in FIG. 7 described in the embodiment, the description thereof is omitted here.

As described above, according to the second embodiment, by using information from the base station of the cellular telephone,
The current position of the wireless communication device is determined, and encryption / decryption processing cannot be performed with a key length exceeding the maximum key length (key length upper limit value) corresponding to the region. Even if the user brings the product out of the originally anticipated area, it can be prevented from being used in a manner that deviates from the regulations set by the competent supervisory organization of the country of export.

The present invention is not limited to the above embodiment, but can be implemented with various modifications within the scope of the invention.

In the above embodiments, the wireless communication device is blue.
Although the case where the tooth interface is mounted has been described, the present invention is not limited to this, and instead, for example, IEEE802.11b, IEEE802.12, IE
The present invention is also applicable to a case where an interface specified by EE 802.15 or the like is mounted.

In each of the above embodiments, the case where the position information detecting units 31 and 41 are operated every time the wireless communication apparatus is turned on is described. Detectors 31, 4
1 may be arbitrarily operated. In this case, even if the position information detecting units 31 and 41 are operated only by manual operation, or the start instruction from the CPU 37 at power-on and an arbitrary start instruction by manual operation are combined, the position information detecting units 31 and 41 are combined. May be operated. As described above, the position information detector 3 is manually operated.
By providing the means for operating the wireless communication devices 1 and 41, for example, even when the wireless communication device is moved to an area having a different specification while the wireless communication device is turned on, the position information detecting units 31 and 41 can be started arbitrarily and the key The length can be immediately adapted to local specifications.

[0057]

As described above in detail, according to the present invention, G
Using the information from the PS satellite or the information from the base station of the cellular phone, the current position of the wireless communication device is determined, and encryption is performed for a key length exceeding the maximum key length (key length upper limit value) corresponding to the area. Encryption / decryption process, so that even if the wireless communication device is taken out of the area originally assumed by the end user, it is determined by the competent supervisory authority of the country of export. It can be prevented from being used out of regulation.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall schematic configuration of a communication system to which the present invention is applied.

FIG. 2 is a block diagram showing a configuration of the wireless communication device according to the first embodiment of the present invention.

FIG. 3 is an exemplary view showing an example of a table stored in a memory according to the embodiment.

FIG. 4 is an exemplary view showing a procedure for calculating a corresponding country (region) from latitude and longitude in the embodiment.

FIG. 5 is an exemplary view showing a procedure for directly deriving a maximum key length from latitude and longitude in the embodiment.

FIG. 6 is a diagram illustrating a Blueto provided in the wireless communication apparatus according to the embodiment;
The figure which shows the outline of the layer structure of an oth interface.

FIG. 7 is a flowchart for explaining the operation in the embodiment.

FIG. 8 is a block diagram showing a configuration of a wireless communication device according to a second embodiment of the present invention.

FIG. 9 is a flowchart for explaining the operation in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Personal computer (personal computer) 12, 14 ... Wireless communication apparatus 13 ... Portable telephone 15 ... Base station 21 ... Communication part 22 ... Transmission / reception module 23 ... Encryption / decryption processing part 24 ... Antenna 31 ... Position information detection part 32 ... Specification control unit 33 ... Antenna 34 ... GPS receiving unit 35 ... Positioning unit 36 ... Memory 37 ... CPU 41 ... Position information detecting unit 42 ... Antenna 43 ... Cellular telephone receiving unit 44 ... Positioning unit

Claims (16)

[Claims] Claims: 1. An encryption / decryption system when a wireless communication device is used.
Means for storing information defining the maximum key length of the decryption key for each area; means for detecting the position of the wireless communication device from a signal transmitted from a GPS satellite; Means for deriving a corresponding maximum key length according to the information stored in the storage means; and means for controlling such that the derived maximum key length limits a key length for encryption / decryption processing in the wireless communication device. A wireless communication device comprising: 2. Encryption / decryption when a wireless communication device is used.
Means for storing information defining the maximum key length of the decryption key for each region; means for detecting the position of the wireless communication device from a signal transmitted from a base station of a cellular telephone; Means for deriving the maximum key length corresponding to the region to which the user belongs, in accordance with the information stored in the storage means; and control so that the key length for encryption / decryption processing in the wireless communication device is limited by the derived maximum key length. A wireless communication device comprising: 3. The storage means stores a table in which a maximum key length of an encryption / decryption key is determined for each of a country subject to export license and a country not subject to export license. The wireless communication device according to claim 1. 4. The wireless communication apparatus according to claim 1, wherein said detecting means detects said position in accordance with an operation command given when power is turned on. 5. The wireless communication apparatus according to claim 1, wherein the detection unit detects the position according to an operation command given by a switch operation. 6. A key length control method for encryption / decryption processing applied to a wireless communication device, wherein a maximum key length of an encryption / decryption key when the wireless communication device is used is set for each region. The determined information is stored in the wireless communication device in advance, a position of the wireless communication device is detected from a signal transmitted from a GPS satellite, and a maximum key length corresponding to an area to which the detected position belongs is determined by:
The key length for encryption / decryption processing is controlled such that the key length for encryption / decryption processing in the wireless communication device is limited by the derived maximum key length in accordance with the stored information. Control method. 7. A key length control method for encryption / decryption processing applied to a wireless communication device, wherein a maximum key length of an encryption / decryption key when the wireless communication device is used is set for each region. The determined information is stored in the wireless communication device in advance, the position of the wireless communication device is detected from a signal transmitted from the base station of the cellular phone, and the maximum key length corresponding to the area to which the detected position belongs. To
The key length for encryption / decryption processing is controlled such that the key length for encryption / decryption processing in the wireless communication device is limited by the derived maximum key length in accordance with the stored information. Control method. 8. The stored information includes a table in which a maximum key length of an encryption / decryption key is determined for each of a country subject to export license and a country not subject to export license. Item 8. The key length control method for encryption / decryption processing according to item 6 or 7. 9. The apparatus according to claim 6, wherein the position detection is performed in accordance with an operation command given when power is turned on.
Or a key length control method for encryption / decryption processing according to 7. 10. The key length control method for encryption / decryption processing according to claim 6, wherein the position detection is performed according to an operation command given by a switch operation. 11. A wireless communication device having a wireless communication function of performing wireless communication with another device, wherein a key used for encryption / decryption of communication information when the wireless communication function is used is classified into the maximum by region. Storage means for storing a key length; detection means for detecting a location area of the wireless communication device; and a maximum key length corresponding to an area detected by the detection means is extracted from the storage means, and the key is extracted. Means for limiting the key length to not more than the set maximum key length. 12. A wireless communication device having a wireless communication function of performing wireless communication with another device, comprising: storage means for storing a region-specific maximum key length of a key used for encrypting / decrypting information; Detecting means for detecting a location area of the wireless communication device; extracting a maximum key length corresponding to the area detected by the detecting means from the storage means, and limiting the key to the extracted maximum key length or less. A wireless communication device comprising: a communication unit that encrypts / decrypts information using a key set by the setting unit and performs wireless communication. 13. A wireless communication device having a wireless communication function for performing wireless communication with another device, wherein a key used for encrypting / decrypting communication information when using the wireless communication function is set to be the maximum for each region. Storage means for storing a key length; detecting means for detecting a location area of the wireless communication device; acquiring means for acquiring information on a maximum key length from a partner device for wireless communication; and a partner device acquired by the acquiring unit. And a means for comparing the maximum key length corresponding to the area detected by the detection means with a maximum key length corresponding to the area detected by the detection means, and limiting the key to a smaller maximum key length or less. Communication device. 14. A key length control method for encryption / decryption processing applied to a wireless communication device having a wireless communication function for performing wireless communication with another device, wherein communication is performed when the wireless communication function is used. A maximum key length for each area of a key used for encryption / decryption of information is stored, a location area of the wireless communication device is detected, and a maximum key length corresponding to the detected area is stored. A key length control method for encryption / decryption processing, wherein the key length is extracted from the maximum key length for each region set in advance and the key is limited to the maximum key length or less. 15. A key length control method for encryption / decryption processing applied to a wireless communication device having a wireless communication function of performing wireless communication with another device, wherein the key length control method is used for information encryption / decryption. The key, the maximum key length by area is stored, the location area of the wireless communication device is detected, and the maximum key length corresponding to the detected area is obtained from the stored maximum key length by area. Extracting and setting the key by limiting it to the extracted maximum key length or less, and performing wireless communication by encrypting / decrypting information using the set key. Key length control method for data processing. 16. A key length control method for encryption / decryption processing applied to a wireless communication device having a wireless communication function of performing wireless communication with another device, the communication being performed when the wireless communication function is used. Storing a maximum key length by area of a key used for encryption / decryption of information, detecting a location area of the wireless communication device, acquiring information on a maximum key length from a partner device of wireless communication, Comparing the acquired maximum key length of the partner device with the maximum key length corresponding to the detected area, and limiting the key to a smaller maximum key length or less. Key length control method.