JP2001320764A - Clone terminal detection system and clone terminal detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize improvement in security of a portable communication system by detecting existence of a clone terminal at an early stage to suppress regular user's damage to the minimum. SOLUTION: The clone terminal detection system holds status information in a portable communication terminal 20 and an exchange 50, respectively, and includes an updating means of the terminal status information to update the status information held in the portable communication terminal on the basis of communication time, an updating means of the exchange status information to update the status information held in the exchange on the basis of the communication time, and an authentication means to judge whether or not the communication is permitted on the basis of the status information held in the portable communication terminal and the status information held in the exchange.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clone terminal detection system and a clone terminal detection method for detecting a counterfeit terminal (clone terminal) that illegally copies internal information of a portable communication terminal such as a portable telephone terminal.

[0002]

2. Description of the Related Art For example, PHS (Personal Ha)
2. Description of the Related Art In a mobile phone system such as an ndyphone system, a call or communication impersonating a legitimate user has been conventionally performed using a forged terminal (clone terminal) in which the internal information of another mobile phone terminal is illegally copied. As a result, the legitimate user of the copy source is charged a large amount of call charges.

[0003] As a measure for avoiding damage caused by unauthorized use of clone terminals, means for detecting the presence of clone terminals has already been proposed. Means for detecting the presence of the clone terminal include, for example, an identification information unauthorized use detection method described in Japanese Patent Publication No. 8-28908 and an unauthorized use of a personal communication terminal described in, for example, JP-A-9-84124. There are methods for preventing use.

According to the method for detecting unauthorized use of identification information and the method for preventing unauthorized use of a personal communication terminal, first, the switching center transmits the number of successful accesses transmitted from the terminal at the time of calling (the number of past calls). And the number of accesses held by the exchange (the number of past calls of the terminal that has made the call request). If the access times do not match, it is detected as a counterfeit terminal.

[0005] On the other hand, if the numbers of calls match, the exchange determines that the terminal is a legitimate terminal and, at the same time, counts up the number of accesses it holds to store the number of accesses. To memorize it. Further, when the call is accepted, the terminal counts up the number of successful accesses and stores it in the storage area of the number of accesses.

With this configuration, the terminal device and the exchange can hold the same access count information counted up each time a call request is accepted. Based on this, a clone terminal can be detected.

[0007]

As described above, in the method of detecting unauthorized use of identification information and the method of preventing unauthorized use of a personal communication terminal, a legitimate terminal is determined by using information on the number of times of access counted up for each number of calls. Had been identified.
For this reason, if the number of accesses is recognized by illegally taking in the communication content during the transmission of the number-of-accesses information, the number of accesses used in the authentication at the next access can be easily predicted.

Therefore, if the number of accesses derived by the unauthorized user based on the information on the number of times of access obtained illegally is taken into the clone terminal as the number of times of access used for the authentication at the time of access, the clone terminal will be authorized by the clone terminal. The same access frequency information as that of the terminal is held.

As described above, the unauthorized user can escape the detection of the clone terminal by incorporating the access frequency information which can be easily predicted from the access frequency obtained from the communication content of the authorized terminal into the clone terminal. Would.
Therefore, the existence of the clone terminal cannot be known at an early stage, and there is a problem that the damage of the user of the legitimate terminal may increase.

It is also conceivable to encrypt the access frequency information so as not to be deciphered even if the access frequency information is obtained illegally. However, in order to perform encryption, a high-level encryption technique must be used, which not only complicates the configuration of the terminal device but also requires many costs. Therefore, the use of encryption technology is not always an appropriate measure.

The present invention solves the above-mentioned problems, and detects the presence of a clone terminal whose content information has been illegally copied at an early stage with a simple configuration, thereby minimizing the damage to authorized users. An object is to improve the security of a communication system.

[0012]

In order to solve the above problems, a clone terminal detection system according to the present invention comprises a portable communication terminal (for example, a PHS terminal device 20) and a base station which performs wireless communication with the portable communication terminal. In a clone terminal detection system including a base station (for example, the base station 40) and an exchange (for example, the exchange 50) connected to the base station, state information (for example, a state number) indicating the state of the mobile communication terminal includes the mobile communication terminal. Terminal status information updating means (for example, a PHS terminal device 20) which is held by the terminal and the exchange and updates the status information held in the portable communication terminal based on the communication time; Exchange status information updating means (for example, base station 40) for updating based on the communication time; status information held in the mobile communication terminal; Based on the status information that is perforated, the authentication means whether to allow communication is determined (e.g., switch 50) is included therein.

[0013] With the above configuration, it is possible to authenticate whether or not the terminal is a legitimate terminal by using the state information changed according to the communication time. It is possible to make it impossible to easily predict, and it is possible to detect the presence of the clone terminal at an early stage. Therefore, with a simple configuration, it is possible to early detect the presence of a clone terminal whose content information has been illegally copied, minimize damage to authorized users, and improve the security of the mobile communication system. it can.

Further, the portable communication terminal and the base station each include a timer for measuring a predetermined time, and the terminal state information updating means updates the state information held in the portable communication terminal.
The mobile communication terminal updates the status information to the status information changed according to the number of times a predetermined time (for example, 30 seconds) is measured by a timer (for example, the timer 33), and the exchange status information updating means is provided in the exchange. The status information may be updated to status information that has been changed according to the number of times the predetermined time has been measured by the timer of the base station.

[0015] With the above configuration, it is possible to authenticate whether or not the terminal is a legitimate terminal by using the status information changed by using the timer measured during the communication time.
The state information used in the next communication cannot be easily predicted, and the presence of the clone terminal can be detected at an early stage.

The status information is a numerical value (for example, a status number) within a predetermined range, and the terminal status information updating means and the exchange status information updating means each determine the number of times the predetermined time has been counted by the timer. May be updated by adding or subtracting from.

[0017] With the above configuration, it is possible to authenticate whether or not the terminal is a legitimate terminal by using a numerical value changed according to the communication time. State information used at the time of communication cannot be easily predicted, and the presence of a clone terminal can be detected at an early stage.

The terminal status information updating means updates the status information based on a communication time from when the portable communication terminal receives a start signal indicating the start of timekeeping to when an end signal indicating the end of timekeeping is transmitted. The switch state information updating means may update the state information based on a communication time from when the base station transmits the start signal to when the base station receives the end signal.

With the above configuration, the terminal status information updating means and the switching equipment status information updating means can change the status information according to substantially the same time, respectively. The held state information can be changed to the same state information.

Further, the exchange status information updating means includes a timer value of a timer of the base station when the base station receives the end signal, and a timer value of the timer of the mobile communication terminal when the portable communication terminal transmits the end signal. Compare with the timer value,
Adjustment means for adjusting the updated state information may be included.

With the above configuration, even if there is a difference in the time for driving the timer between the terminal status information updating means and the exchange status information updating means, the status information to be changed can be adjusted and matched. The status information held by the terminal and the exchange can be changed so that they are the same status information.

Further, the clone terminal detecting method of the present invention comprises:
When performing communication using a mobile communication terminal, in a clone terminal detection method that detects whether there is a clone terminal by checking whether the communication is a legitimate terminal, state information held in the mobile communication terminal, A step of determining whether to permit communication based on the state information held by the exchange, and a step of updating the state information held in the mobile communication terminal based on the communication time; and Updating the status information based on the communication time.

With the above configuration, it is possible to authenticate whether the terminal is a legitimate terminal by using the state information changed according to the communication time. It is possible to make it impossible to easily predict, and it is possible to detect the presence of the clone terminal at an early stage. Therefore, with a simple configuration, it is possible to early detect the presence of a clone terminal whose content information has been illegally copied, minimize damage to authorized users, and improve the security of the mobile communication system. it can.

Updating the status information held by the mobile communication terminal to status information changed according to the number of times a timer of the mobile communication terminal has counted a predetermined time;
Updating the status information held by the exchange to status information changed according to the number of times the timer of the base station has counted a predetermined time.

[0025] With the above configuration, it is possible to authenticate whether or not the terminal is a legitimate terminal by using the status information changed using the timer measured during the communication time.
The state information used in the next communication cannot be easily predicted, and the presence of the clone terminal can be detected at an early stage.

The state information held by the portable communication terminal is updated based on the communication time from when the portable communication terminal receives the start signal indicating the start of timekeeping to when the portable communication terminal transmits the end signal indicating the end of timekeeping. And updating the state information held by the exchange based on the communication time from when the base station transmits the start signal to when the base station receives the end signal.

With the above configuration, the state information held by the portable communication terminal and the state information held by the exchange can be changed at substantially the same time, and the state information held by the terminal and the state information held by the exchange can be changed. Status information can be changed to the same status information.

Further, the timer value of the timer of the base station when the base station receives the end signal is compared with the timer value of the timer of the mobile communication terminal when the mobile communication terminal transmits the end signal. And adjusting the status information to be updated.

With the above configuration, even if there is a difference in the time for driving the timer between the portable communication terminal and the base station,
Since the state information to be changed can be adjusted and matched, the state information held in the terminal and the state information held in the exchange can be changed so as to be the same state information.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. In this example,
The configuration and processing of the clone terminal detection system when detecting a clone terminal in which the internal information (for example, ROM) of the PHS terminal device that is a mobile communication terminal has been illegally copied will be described.

FIG. 1 shows the configuration of the clone terminal detection system 10 of the present embodiment. The clone terminal detection system 10 includes a PHS terminal device 20, a base station 40, an exchange 50, and a subscriber information database 51.

The PHS terminal 20 is, for example, a base station 40
The wireless communication terminal device is connected to a communication device such as a telephone (for example, another mobile phone terminal) via the PHS system, and performs a telephone call, information communication, and the like using a PHS system.

As shown in FIG. 2, for example, the PHS terminal device 20 includes an antenna unit 21, a transmission / reception unit 22, a baseband processing unit 23, a CPU 24, a receiver 25, a microphone 26, a display unit 27, Input unit 28, vibrator 29, sounder 30, driver unit 31
And a terminal information storage unit 32 and a timer 33.

The antenna section 21 transmits and receives a radio signal. The transmission / reception unit 22 performs signal amplification, frequency conversion, and the like. The baseband processing unit 23 modulates and demodulates the signal. The CPU 24 is a control device that performs various controls of the entire device 20. The display unit 27 is configured by, for example, an LCD, and displays various information such as a telephone number and time.

The input section 28 includes, for example, a number button and an off-hook button, and is used to input various information. The vibrator 29 is a vibration motor that notifies a user of an incoming call by vibration. Sounder 30
For example, it is configured by a speaker or the like, and outputs a ringtone or the like.

In the present embodiment, the terminal information storage section 32 stores various terminal information such as a terminal ID and a state number.
The state number is state information indicating the state of the terminal device 20, and is stored in, for example, a rewritable storage area constituted by a RAM. The timer 33 is connected to the CPU 24
Is measured for a predetermined time based on the control of.

The base station 40 is, for example, the PHS terminal 20
For example, information is transmitted to and received from a subscriber terminal using a wireless signal. Further, the base station 40 calls the PHS terminal device 20 that made the call and the exchange 50 by specifying a communication channel, and calls the called mobile phone terminal device in response to the incoming call notification from the base station 50, It has various functions such as a function of wirelessly connecting the exchange 50 and a destination mobile phone terminal by designating a communication channel.

The transmission and reception of information using a radio signal between the base station 40 and the PHS terminal device 20 is performed in this example by TD
This is realized by the MA (Time Division Multiple Access) method. Therefore, in wireless communication between the base station 40 and the PHS terminal device 20, when receiving data (control data or PCM voice data), data is extracted from a predetermined time slot corresponding to the control channel or the communication channel. Received. When transmitting data, the data is inserted into a predetermined time slot and transmitted.

In this example, the base station 40 has a storage area (not shown) for temporarily holding the status numbers of the terminals using the communication channels corresponding to the plurality of communication channels of the base station 40. are doing. In this example, the base station 40 has a timer (not shown) for measuring time corresponding to each communication channel. That is, the base station 40 has, for example, a storage area for holding a state number and a timer for each communication channel that can be assigned to the terminal side.

The exchange 50 is connected to a plurality of base stations such as the base station 40. The exchange 50 has, for example, IS
A line network such as a DN line or a PSTN line is connected. The exchange 50 executes a procedure for setting up a call with the PHS terminal device 20 that has originated a call via the base station 40, and performs various functions such as a function of connecting the PHS terminal device 20 to a communication device of the other party. have.

In addition to the function of confirming whether or not the calling terminal is a subscriber terminal based on the terminal ID, the exchange 50 also confirms whether or not the calling terminal is a legitimate subscriber terminal based on the status number in this example. It also has the function of performing

The exchange 50 has a subscriber information database 5
1 and authenticates the calling terminal using the information stored in the subscriber information database 51. Therefore, the subscriber information database 51 stores various information including the ID of each subscriber terminal and the state number corresponding to each subscriber terminal. In the subscriber information database 51, for example, the telephone number is used as a key, and the ID and the state number of each terminal are registered in association with each other.

Next, the clone terminal detection system 1 of this embodiment
0 will be described with reference to FIG. 3 and FIG.

FIG. 3 is a timing chart showing clone terminal detection processing and processing timing in the clone terminal detection system 10 of this embodiment.

First, when the input unit 28 is operated and the PHS terminal device 20 makes a call by designating, for example, the number of the other terminal to be communicated with (step S301), the number of the other terminal and the terminal information storage unit 32 Own terminal I stored in
D and the state number are transmitted to the base station 40.

Upon receiving a call request from PHS terminal device 20, base station 40 stores a storage area having a state number contained in the received data (in this example, a call area assigned to PHS terminal device 20). (The storage area corresponding to the channel) (step S302), and
The received data relating to the call request is transferred to 0 (step S303).

Upon receiving data related to a call from the PHS terminal device 20 via the base station 40, the exchange 50
The terminal ID input from the PHS terminal device 20 is compared with the terminal ID stored in the subscriber information database 51 (in this example, the terminal ID associated with the telephone number of the PHS terminal device 20) to make a call. PHS terminal device 2
Check whether 0 is a subscriber terminal (step S3).
04).

Terminal ID input from PHS terminal device 20
And the terminal I stored in the subscriber information database 51
If D does not match, exchange 50 determines that the call is from a non-subscriber terminal and refuses to accept communication (step S305).

If the terminal IDs match and it is confirmed that the terminal is a subscriber terminal, the exchange 50 stores the state number input from the PHS terminal 20 via the base station 40 and the subscriber information database 51. And confirms whether or not the calling PHS terminal device 20 is a legitimate subscriber terminal by comparing the state number (in this example, the state number associated with the telephone number of the PHS terminal device 20). (Step S306).

If the status number input from PHS terminal device 20 does not match the status number stored in subscriber information database 51, exchange 50 determines that a clone terminal is present and switches the clone terminal. Since there is a possibility that the call was used, the reception of the communication is rejected (step S305).

Then, the base station 50 notifies the system administrator that the presence of the clone terminal has been detected, for example, by displaying a warning on a display unit (not shown). When the detection of the presence of the clone terminal is notified, the system administrator sets, for example, such that communication based on the terminal ID of the calling terminal is not accepted, and the normal After that, the terminal user is notified of the existence of the clone terminal, and other measures are taken.

When the status numbers match and it is confirmed that the subscriber terminal is a legitimate subscriber terminal, the exchange 50 sets the base station 4
0 is notified that a call from the PHS terminal device 20 will be accepted (step S307).

When the PHS terminal device 20 that has made the call is authenticated and notified that the call is to be accepted, the base station 40
Selects a communication channel from available channels and
It is specified for the S terminal device 20. When the communication channel is specified, the PHS terminal device 20 sets the communication channel according to the instruction from the base station 40.

When a communication channel is set in the PHS terminal device 20, in the clone terminal detection system 10 of this embodiment, radio communication using the communication channel is started between the PHS terminal device 20 and the base station 40. If the partner terminal responds to the incoming call, communication between the PHS terminal device 20 and the partner terminal is started.

In this case, in this example, the base station 40
When the first time slot is transmitted to the S terminal device 20 using the communication channel (step S30)
8) The timer is started by a timer provided corresponding to the communication channel (step S309).

In this example, the PHS terminal device 20
When the first time slot transmitted from the base station 40 is received using the communication channel (step S31).
0), the timer 33 starts counting time (step S3)
11).

Therefore, in the base station 40 and the PHS terminal device 20, clocking by the timer is started almost simultaneously.
It should be noted that the timers of the base station 40 and the PHS terminal are started almost simultaneously (in this example, the timer of the base station 40 is configured to start the timer first). If so, another timing may be used.

When the timer 33 starts counting time, PH
For example, as shown in FIG.
Each time 3 measures a predetermined time (for example, 30 seconds), the state number is counted up and the timer 33 is returned to the initial value.

Similarly, the base station 40 is, for example,
As shown in (2), when the timer starts counting, each time the timer corresponding to the communication channel measures a predetermined time (for example, the same time as the predetermined time measured by the timer 33), the storage area corresponding to the communication channel. The timer increments the state number held in, and returns the timer to the initial value.

In this example, when the state number is counted up to a certain number, the state number returns to the initial value by making a round. In this case, the larger the maximum value of the state number is, the lower the possibility of overlapping with the state number of the clone terminal can be. However, the storage medium capacity of the PHS terminal device 20 and the base station 40 is increased. I have to. Therefore, the maximum value of the state number is determined to be an appropriate value in consideration of the above benefits and disadvantages.

Then, the input unit 2 for terminating the communication
8 is operated, the PHS terminal device 20
To the client (step S3).
12) Stop the timer 33 and transmit the timer value at the time of stopping (step S313). That is, in this example,
The PHS terminal device 20 stops the timer 33 when transmitting the release request.

In addition, the PHS terminal device 20 displays the counted number of the state (if the timer 33 has not counted a predetermined time (30 seconds in this case) during communication, it has not
The same state number as at the start of communication) is stored and updated in the terminal information storage unit 32 (step S314).

When receiving the release request from the PHS terminal device (step S315), the base station 40 transfers the release request to the exchange 50, and stops counting the time corresponding to the PHS terminal device 20 (step S31).
6). The exchange 50 that has received the release request disconnects the communication between the PHS terminal device 20 and the partner terminal. in this way,
In this example, the base station 40 stops the timer when receiving the release request.

When the timer stops counting, the base station 40
Performs an adjustment process for matching the new state number obtained by the processing of the PHS terminal device 20 with the new state number obtained by itself.

In this example, the timer 3 of the PHS terminal 20
The internal timer of the base station 40 starts counting time earlier than the timer of the base station 3, and the base station 4
The internal timer of 0 is stopped later. Therefore, the new state number obtained by the processing of the base station 40 may have a larger value than the new state number obtained by the processing of the PHS terminal device 20.

That is, when the state number is counted up every 30 seconds, for example, the timer 33 of the PHS terminal device 20 is stopped at 29.99 seconds, for example, and the timer of the base station 40 is stopped at 0.01 seconds. Means that the base station 40 has counted up the state number one more time. Therefore, the state number obtained by the base station 40 becomes one larger than the state number obtained by the PHS terminal device 20. As a countermeasure in such a case, the base station 40 performs an adjustment process.

In the PHS system, since the distance between the terminal and the base station is relatively short, the timer value shifts in milliseconds, and the state number does not shift by 2 or more. Further, in a mobile phone system including a PHS system, for example, a configuration may be employed in which a state number is not shifted by two or more by adjusting a set time of a timer for counting up a state number.

In the adjustment process, the base station 40
The timer value input from the terminal device 20 is compared with the timer value of the stopped internal timer (step S317).

If the value of the timer value input from PHS terminal device 20 is larger (Y in step S317), base station 40 is stored in the storage area corresponding to the communication channel used by PHS terminal device 20. Then, the status number is decremented by one and transmitted to the exchange (step S319).

On the other hand, if the value of the timer value input from PHS terminal device 20 is smaller (N in step S 317), base station 40 stores in the storage area corresponding to the communication channel used by PHS terminal device 20. The held state number is transmitted to the exchange as it is (step S31).
9).

When a state number is input from the base station 40,
The exchange 50 updates the status number corresponding to the PHS terminal device 20 stored in the subscriber information database 51 to the received status number (Step S320).

Next, when communication is performed using the PHS terminal device 20 next time, a new state number (if the timer 33 has not counted for a predetermined time or more, the communication start The same state number as at the time) confirms whether the terminal is a legitimate subscriber terminal.

If the communication does not end normally for some reason, the PHS terminal 20 and the base station 40
Returns the state number to the initial value (the value at the start of communication).

As described above, in the clone terminal detection system 10 of the present embodiment, the state number used for detecting the clone terminal at the time of the next communication is updated in the PHS terminal device 20 and the subscriber information database. Then, the clone terminal detection processing ends.

As described above, since the state number held in the terminal and the subscriber information database is changed and updated according to the communication time, the state number used in the next communication can be easily changed. Prediction cannot be made, and the presence of a clone terminal can be detected early. Therefore, with a simple configuration, it is possible to early detect the presence of a clone terminal whose content information has been illegally copied, minimize damage to authorized users, and improve the security of the mobile communication system. it can.

Further, as described above, the state number is transmitted only once between the terminal and the base station before the communication with the other party is started, and the state number is changed and updated according to the communication time. With this configuration, the risk of acquiring the state number can be minimized, and even if the state number has been acquired, the state changed with the passage of time thereafter. Since it is possible to prevent the number from being easily predicted, it is possible to prevent the state number used in the next communication from being predicted and being easily escaped from the detection of the clone terminal,
The presence of the clone terminal can be detected at an early stage.

Further, as described above, since the adjustment processing in base station 40 is performed based on the timer value, the state number is known even if the timer value is obtained by a third party. Therefore, it is possible to prevent the state number used in the next communication from being predicted, and to detect the presence of the clone terminal at an early stage.

In the above-described embodiment, when a call is received, a status number is transmitted to authenticate whether the terminal is a legitimate terminal. The configuration may be such that the terminal is transmitted to the base station to authenticate whether the called terminal is a legitimate terminal. Further, at another time, for example, at the time of location registration of the terminal, the status number may be transmitted to the corresponding base station to authenticate whether the terminal is a legitimate terminal.

In the above-described embodiment, the state number is counted up each time the timer measures a predetermined time, and the timer is returned to the initial value.
Each time the timer measures a predetermined time, the state number may be counted down and the timer may be returned to the initial value. In this case, in the adjustment processing in the base station 40, if the value of the timer value input from the PHS terminal device 20 is larger, the state number held in the storage area provided corresponding to the communication channel is incremented by one. Then, it may be transmitted to the exchange.

Further, in the above-described embodiment, a timer for counting up time and counting time is assumed, and the state number is counted up each time the timer counts a predetermined time, and the timer is returned to the initial value. However, when measuring the predetermined time, a timer that counts down the time and measures the time may be used. In this case, in the adjustment process in the base station 40, if the value of the timer provided for the corresponding communication channel of the base station 40 is larger, the value is stored in the storage area provided for the communication channel. It is sufficient to subtract 1 from the status number that is present and transmit it to the exchange.

In the above-described embodiment, the processing at the time of handover (the function of switching the base station which performs wireless communication and maintaining communication with the other party when the PHS terminal device 20 moves during communication) is described. Is not particularly described, but at the time of handover, for example, the following processing may be performed.

For example, the PHS terminal 20 first starts the timer 3 when the wireless communication with the base station of the switching source is disconnected.
3 is initialized. On the other hand, when the wireless communication with the PHS terminal device 20 is disconnected, the switching source base station changes the currently held state number (the changed state number if changed) to the switching destination base station. Transfer to the station. In addition, as in the above-described embodiment, the switching destination base station starts a timer provided according to the communication channel when wireless communication with the PHS terminal device 20 is started. And PHS
The terminal device 20 restarts the timer 3 when the wireless communication with the switching destination base station is started, as in the above-described embodiment.
Start 3

When the base station of the switching source disconnects the wireless communication with the PHS terminal device 20, the initial value of the state number (the state number at the start of communication) is transmitted to the base station of the switching destination. You may make it transfer. In this case, when the wireless communication with the switching source base station is disconnected, the PHS terminal device 20 initializes the timer 33 and also initializes the state number (returns to the state number when communication was started). ).

As described above, if the processing at the time of handover is performed, even if the terminal moves and is handed over during communication, the state number is set so that the terminal and the exchange maintain the same state number. Can be changed. Further, at the time of handover, there is no need to wirelessly transmit the state number from the terminal, so that the state number is not acquired by a third party.

Further, in the above-described embodiment, the state number is used as the state information indicating the state of the terminal, but information other than the number such as, for example, character information is ordered according to a predetermined rule (for example, , Alphabet, etc.).

Further, in the above-described embodiment, the PHS
The driving time of the timer 33 of the terminal device 20 is longer than the base station 4
Although the driving time of the timer 0 is configured to be longer, the reverse may be possible. In this case, if the driving time of the timer 33 of the PHS terminal device 20 is configured to be longer, the adjustment process in the base station 40 may be performed in accordance with the driving time.

In the above-described embodiment, the PHS terminal device 20 is used as an example of the portable communication terminal.
Needless to say, the present invention can be applied to a mobile phone terminal device and a mobile communication terminal device other than the terminal device.

Further, in the above-described embodiment, when transmitting the first time slot using the communication channel, the base station 40 starts counting time using a timer,
The PHS terminal 20 starts time counting by the timer 33 when receiving the first time slot transmitted from the base station 40 using the communication channel, and the PHS terminal 20 sets the timer 33 when transmitting the release request. And the base station 40 terminates the time measurement by the timer when the release request is received, but any other timing may be used as long as the communication is started or terminated. Of course.

[0089]

As described above, according to the clone terminal detection system of the present invention, a clone terminal including a portable communication terminal, a base station for performing wireless communication with the portable communication terminal, and an exchange connected to the base station. In the detection system, state information indicating the state of the mobile communication terminal is held by the mobile communication terminal and the exchange, respectively, terminal state information updating means for updating the state information held in the mobile communication terminal based on the communication time, Exchange state information updating means for updating the state information held in the exchange based on the communication time;
Since it includes authentication means for determining whether to permit communication based on the status information held in the mobile communication terminal and the status information held in the exchange, it is changed according to the communication time. Can be used to authenticate whether the terminal is a legitimate terminal, so that the state information used in the next communication cannot be easily predicted, and the presence of a clone terminal Can be detected early. Therefore, with a simple configuration, it is possible to early detect the presence of a clone terminal whose content information has been illegally copied, minimize damage to authorized users, and improve the security of the mobile communication system. it can.

Further, each of the portable communication terminal and the base station includes a timer for measuring a predetermined time, and the terminal state information updating means updates the state information held in the portable communication terminal.
The mobile communication terminal updates the status information with the status information changed according to the number of times the predetermined time is counted by the timer provided in the mobile communication terminal, and the exchange status information updating means updates the status information held in the exchange by the timer provided in the base station. If the status is updated to the status information changed according to the number of times the time is measured, whether the terminal is a legitimate terminal using the status information changed using the timer clocked during the communication time Since it is possible to authenticate whether or not the state information used in the next communication can not be easily predicted, the presence of the clone terminal can be detected at an early stage.

The status information is a numerical value within a predetermined range, and the terminal status information updating means and the exchange status information updating means add or subtract the number of times the predetermined time is counted by the timer to or from the status information, respectively. In the case of updating, it is possible to authenticate whether the terminal is a legitimate terminal by using the numerical value changed according to the communication time, so the simple configuration of changing the numerical value enables the next communication In this case, it is possible to prevent the state information used in such a case from being easily predicted, and it is possible to detect the presence of the clone terminal at an early stage.

Further, the terminal status information updating means updates the status information based on the communication time from when the portable communication terminal receives the start signal indicating the start of timing to when it transmits the end signal indicating the end of timing. When the base station updates the state information based on the communication time from when the base station transmits the start signal to when the base station receives the end signal, the switch state information updating means includes a terminal state information updating means. ,
The switching unit status information updating means can change the status information according to substantially the same time, and can change the status information held by the terminal and the switching device to the same status information.

Further, the exchange status information updating means includes a timer value of a timer of the base station when the base station receives the end signal, and a timer value of the timer of the mobile communication terminal when the mobile communication terminal transmits the end signal. Compare with the timer value,
When the updated state information includes adjusting means for adjusting the state information, the state information to be changed is changed even if there is a difference in the time for driving the timer between the terminal state information updating means and the exchange state information updating means. Since adjustment and matching can be performed, it is possible to change the state information held by the terminal and the exchange to be the same state information.

Further, according to the clone terminal detecting method of the present invention, when performing communication using a portable communication terminal, the clone terminal detects whether or not the communication is by a legitimate terminal and detects the presence of the clone terminal. In the detection method, the method includes a step of determining whether to permit communication based on state information held in the mobile communication terminal and state information held by the exchange, wherein the state information held in the mobile communication terminal is included. Updating based on the communication time;
And updating the state information held in the exchange based on the communication time. Authentication can be performed. For this reason, it is possible to prevent the state information used in the next communication from being easily predicted, and it is possible to detect the presence of the clone terminal at an early stage. Therefore,
With a simple configuration, the presence of a clone terminal whose content information has been illegally copied can be detected at an early stage, damage to an authorized user can be minimized, and the security of the mobile communication system can be improved.

Updating the status information held by the mobile communication terminal to status information changed according to the number of times a timer of the mobile communication terminal has counted a predetermined time;
And updating the status information held by the exchange to status information changed according to the number of times the timer of the base station has counted the predetermined time. Since it is possible to authenticate whether the terminal is a legitimate terminal by using the state information changed by using, it is possible to make it impossible to easily predict the state information used in the next communication, The presence of the clone terminal can be detected at an early stage.

Further, the state information held by the portable communication terminal is updated based on the communication time from when the portable communication terminal receives the start signal indicating the start of timekeeping to when the portable communication terminal transmits the end signal indicating the end of timekeeping. And the step of updating the state information held by the exchange based on the communication time from when the base station transmits the start signal to when the base station receives the end signal. The state information held by the mobile communication terminal and the state information held by the exchange can be changed according to the time of the mobile communication terminal, and the state information held by the terminal and the state information held by the exchange can be changed to the same state information. it can.

Further, the timer value of the timer of the base station when the base station receives the end signal is compared with the timer value of the timer of the mobile communication terminal when the mobile communication terminal transmits the end signal. In the case where the step of adjusting the state information to be updated is included, the state information to be changed can be adjusted to match even if there is a difference in the time for driving the timer between the mobile communication terminal and the base station. Therefore, it is possible to change the status information held by the terminal and the exchange so that they are the same status information.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a clone terminal detection system according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a PHS terminal device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an example of clone terminal detection processing and processing timing of the clone terminal detection system according to one embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an example of a process of changing a state number according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 clone terminal detection system 20 PHS terminal device 21 antenna unit 22 transmitting / receiving unit 23 baseband processing unit 24 CPU 32 terminal information storage unit 33 timer 40 base station 50 exchange 51 subscriber information database

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04L 11/00 310B F-term (Reference) 5J104 AA07 KA02 PA02 5K027 AA11 BB09 EE01 GG08 HH11 5K033 AA08 CB06 DA01 DA19 DB20 EA03 5K051 CC07 DD01 DD15 EE06 FF02 FF21 HH02 HH12 KK00 5K067 AA32 BB04 DD30 EE02 EE10 EE16 FF05 HH23

Claims (9)

[Claims] 1. A clone terminal detection system including a mobile communication terminal, a base station that performs wireless communication with the mobile communication terminal, and an exchange connected to the base station, wherein state information indicating a state of the mobile communication terminal is provided. Is held by the mobile communication terminal and the exchange, respectively, terminal status information updating means for updating the status information held in the mobile communication terminal based on the communication time, the state information held in the exchange An exchange status information updating unit that updates based on the communication time, status information held in the portable communication terminal, and status information held in the exchange determine whether to permit communication. A clone terminal detection system, comprising: 2. The mobile communication terminal and the base station, respectively,
A timer for measuring a predetermined time, wherein the terminal status information updating means changes the status information held in the mobile communication terminal according to the number of times the predetermined time has been measured by the timer of the mobile communication terminal. The state information is updated, and the exchange state information updating means updates the state information held in the exchange to state information changed according to the number of times that a predetermined time is measured by a timer of the base station. The clone terminal detection system according to claim 1, wherein: 3. The status information is a numerical value within a predetermined range, and each of the terminal status information updating means and the exchange status information updating means adds or subtracts the number of times a predetermined time is counted by the timer to or from the status information. 3. The clone terminal detection system according to claim 2, wherein the system is updated. 4. The terminal state information updating means updates the state information based on a communication time from when the portable communication terminal receives a start signal indicating the start of timekeeping to when an end signal indicating the end of timekeeping is transmitted. The switching unit status information updating means updates the status information based on a communication time from when the base station transmits the start signal to when the base station receives the end signal. 3. The clone terminal detection system according to 3. 5. The exchange status information updating means includes a timer value of a timer of the base station when the base station receives the end signal, and the portable communication terminal when the mobile communication terminal transmits the end signal. 5. The clone terminal detection system according to claim 4, further comprising an adjusting unit that compares the updated state information with a timer value of the timer. 6. When performing communication using a portable communication terminal,
In a clone terminal detection method for detecting the presence of a clone terminal by confirming whether communication is performed by a legitimate terminal, based on state information held in the mobile communication terminal and state information held by the exchange, A step of determining whether to permit communication; a step of updating state information held in the mobile communication terminal based on a communication time; and a step of updating state information held in the exchange based on the communication time. Updating the clone terminal. 7. A step of updating state information held by the mobile communication terminal to state information changed according to the number of times a timer of the mobile communication terminal has counted a predetermined time; 7. The method according to claim 6, further comprising the step of: updating the status information to the status information changed according to the number of times the timer of the base station has counted the predetermined time. 8. The state information held by the mobile communication terminal based on a communication time from when the mobile communication terminal receives a start signal indicating the start of timekeeping to when an end signal indicating the end of timekeeping is transmitted. Updating, based on a communication time from when the base station transmits the start signal to when the base station receives the end signal, updating the state information held by the exchange. The clone terminal detection method according to claim 6 or 7. 9. A timer value of a timer of the base station when the base station receives the end signal is compared with a timer value of a timer of the mobile communication terminal when the mobile communication terminal transmits the end signal. 9. The method according to claim 8, further comprising the step of adjusting the status information to be updated.