JP2006186484A - Verification system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a verification system in which unauthorized access can be prevented even when the information of a key medium such as a card is read out. <P>SOLUTION: When verification is performed in a verification system 1 by reading out information held on a key medium 100 by means of a verifier, the verifier receives an ID and an operation number from the key medium 100, creates a restoration number based on the received operation number and stored number of times, and then decision is made based on the fact whether the restoration number matches an eigen-number corresponding to that ID or not. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a collation system that performs collation by ID (Identification) or the like.

  Traditionally, when opening a door of a building or operating a vehicle, a person with a valid key or card has to perform a predetermined operation to gain access by a malicious person. It is preventing.

However, for example, in a key having a concave and convex shape and its lock, illegal unlocking due to duplication of the key or so-called picking does not stop. Thus, as a countermeasure against such unauthorized unlocking, collation using a magnetic card, an IC (Integrated Circuit) card, or the like is also widespread.
Further, for example, Patent Document 1 discloses a technique that further increases security by limiting the number of times or time of use for an encryption key.
JP 2000-295209 A (paragraphs 0007 to 0012, FIG. 3)

However, with regard to key media such as cards (mediums held by the operator such as keys and cards) regardless of whether they are contact-type or non-contact-type, the above-mentioned readers have become more sophisticated, and the like None of the conventional techniques are perfect countermeasures. In other words, unauthorized access becomes possible because information held in the key medium is illegally read and used.
Therefore, an object of the present invention is to provide a verification system that can prevent unauthorized access even when information on a key medium such as a card is read.

In order to solve the above-mentioned problem, the invention according to claim 1 is a verification system in which a verification device reads information stored in a key medium and performs verification, and the verification device includes the ID of the key medium, the ID And a collation device storage unit for storing the unique number used in the computation and the number of times the key medium has been used, and collation device processing for creating the computation number from the computation based on the unique number and the number of times The key medium includes a key medium storage unit that stores the ID and the number of operations received from the verification device, and the verification device processing unit includes the ID and the ID from the key medium. The calculation number is received, and a restoration number is created from the calculation based on the received calculation number and the number of times corresponding to the ID stored in the collation device storage unit, and the restoration number is the eigennumber Judgment based on whether or not they match And performing.
The invention according to claim 2 is a verification system in which a verification device reads information stored in a key medium and performs verification, and the verification device is used for calculation corresponding to the ID of the key medium and the ID. An eigennumber, and a collation device storage unit that stores the number of times the key medium has been used, and a collation device processing unit that creates an operation number from an operation based on the eigennumber and the number of times, The key medium includes a key medium storage unit that stores the ID and the calculation number received from the verification device, and the calculation number includes a time length of a transmission time of all or part of communication information including the ID. And a key medium communication unit that transmits communication information to the collation device, and the collation device processing unit transmits all or part of the communication information received from the key medium communication unit. The number of operations is recognized from the time length of A restoration number is created from the computation based on the number of computations and the number of times corresponding to the ID stored in the collation device storage unit, and collation determination is performed based on whether or not the restoration number matches the eigennumber It is characterized by performing.

The invention according to claim 3 is characterized in that the collation device processing unit changes the unique number stored in the collation device storage unit to any other number at a predetermined timing. A collation system according to claim 2.
The invention according to claim 4 is a collation system in which the information held by the key medium is read by the reading device, and the receiving device collates based on the information received from the reading device. An ID, a unique number used for calculation corresponding to the ID, and a reception device storage unit that stores the number of times the key medium has been used; and a reception device processing unit that performs calculation processing; , A reader storage unit for storing the ID, the eigennumber and the number of times, a reader processing unit for generating a calculation number from an operation based on the eigennumber and the number of times, and communicating information to the receiver The key medium has a key medium storage unit that stores the ID and the number of operations received from the reader, and the key medium, the reader, and the receiver By The reading device processing unit creates a restoration number from a calculation based on the number of times stored in the reading device storage unit and the calculation number received from the key medium, and the reading device communication unit When transmitting the ID, the number of restorations, and the number of times to the receiving device, the number of times is converted into a time length with a predetermined voltage and transmitted, and the receiving device processing unit receives the number of restorations received and The collation is determined based on whether or not the number of times matches the unique number and the number of times stored in the receiving device storage unit.

According to the first aspect of the present invention, the number of operations used for collation is calculated from the eigennumber and the number of times, and therefore changes every time. As a result, even if the number of operations stored in the key medium is read, it is unlikely that it will be used for verification. Further, since the number of operations can be changed with arbitrary regularity, the risk of knowing the regularity is low, and the possibility of unauthorized access can be kept low.
According to the second aspect of the present invention, when communication information is transmitted from the key medium to the verification device, the number of operations is converted into a time length of all or part of the communication information and transmitted. Thus, unauthorized access by decoding communication information can be made more difficult.
Further, according to the invention of claim 3, by changing not only the number of times but also the eigennumber at a predetermined timing, even when information on a key medium such as a card is read, the rule of change in the number of operations The possibility of knowing sex can be further reduced.
According to the fourth aspect of the present invention, when the ID, the number of restorations, and the number of times are transmitted from the reading device to the receiving device, the number of times is converted into a time length with a predetermined voltage and transmitted, thereby transmitting information. Can be made more difficult and the possibility of unauthorized access can be further reduced.

Hereinafter, embodiments according to the verification system of the present invention will be described in the order of configuration and operation with reference to the drawings.
(Constitution)
FIG. 1 is an overall configuration diagram of the verification system. The verification system 1 includes a key medium 100, a reading device 200, and a receiving device 300. For example, the key medium 100 is realized by an IC card, the reading device 200 is realized by a card reader, and the receiving device 300 is realized by a PC (Personal Computer). In that case, the collation system 1 can perform entrance / exit management by connecting a PC to an electric lock or the like at the entrance / exit of a building.
Needless to say, the place where entrances and exits of buildings are managed can be widely applied not only to entrances and exits to the outside such as entrance doors, doors to doors, and emergency doors, but also to indoor doors in buildings.

When collation with the key medium 100 is performed in the collation system 1 (determination as to whether or not the person having the key medium 100 is a valid person), first, the reader 200 reads information held by the key medium 100. Next, the reading device 200 transmits the read information to the receiving device 300. The collation is performed by the receiving apparatus 300. The reading apparatus 200 and the receiving apparatus 300 are integrated as an apparatus (corresponding to “collating apparatus” in claims 1 and 2 of the claims). It may be configured.
In FIG. 1, only one key medium 100 exists, but a plurality of key media 100 may exist. Further, it is assumed that the key medium 100 and the reading device 200 perform wireless communication, and the reading device 200 and the receiving device 300 perform wired communication, but the communication method is not limited thereto.

Next, each configuration will be described in detail.
<Key medium>
The key medium 100 includes a storage unit (key medium storage unit) 110 and a communication unit 120. When the verification system 1 is used for building access control, the key medium 100 is realized by, for example, an IC card held by a person entering and exiting the building.
The storage unit 110 stores information, and functions as, for example, a part of an IC chip. The storage unit 110 stores at least an ID 111 that is an identifier of the key medium 100 and a total number (details will be described later) 112 received from the reading device 200.

The communication unit 120 performs communication, and is, for example, a wireless communication device. The communication unit 120 transmits the ID 111 and the total number 112 stored in the storage unit 110 to the reading device 200, and stores the total number received from the reading device 200 as the total number 112 in the storage unit 110. Further, the communication unit 120 may have a function of transmitting the communication information by converting the total number 112 into the time length of all or part of the communication information, in which case processing means (illustrated) None) may be included.
The key medium 100 may be operated by an internal power source (not shown), or may be of an electromagnetic induction type that converts radio waves from the reading device 200 into electric power. May be.

<Reader>
The reading device 200 includes a storage unit (reading device storage unit) 210, a processing unit 220 (reading device processing unit), a first communication unit 230, and a second communication unit 240 (reading device communication unit). When the verification system 1 is used for entrance and exit management of a building, the reader 200 is realized by a card reader that reads an IC card that is the key medium 100, for example.
The storage unit 210 stores information, and is, for example, a memory, a RAM (Random Access Memory), a ROM (Read Only Memory), or the like. The storage unit 210 stores at least the ID 211 that is the identifier of the key medium 100 and the unique number and the number of times received from the receiving device 300 as the unique number 212 and the number of times 213.

  The processing unit 220 performs various arithmetic processes, and is, for example, a CPU (Central Processing Unit). The processing unit 220 creates a calculation number by performing a calculation based on the unique number 212 and the number of times 213 stored in the storage unit 210, or communicates with the key medium 100 via the first communication unit 230. The communication with the receiving device 300 is performed via the second communication unit 240. In addition, when the key medium 100 transmits the communication information by converting the total number 112 into the time length of all or part of the communication information, the processing unit 220 uses the communication information received from the key medium 100. It has a function of recognizing the total number 112.

The first communication unit 230 is a device that relays communication between the processing unit 220 and the key medium 100, and is, for example, a wireless communication device.
The second communication unit 240 is a device that relays communication between the processing unit 220 and the reception device 300, and is, for example, a wired communication interface.

<Receiving device>
The receiving device 300 includes a storage unit (receiving device storage unit) 310, a collation unit (receiving device processing unit) 320, a numerical value updating unit 330, and a communication unit 340. When the verification system 1 is used for building access management, the receiving device 300 is realized by, for example, a control device (such as a PC) that controls (opens and closes) an electric lock of an entrance door of the building.
The storage unit 310 stores information, and is, for example, a memory, a RAM, a ROM, or the like. The storage unit 310 stores at least ID 311 that is an identifier of the key medium 100, a unique number 312 corresponding to the ID 311, and the number of times the key medium 100 has been used as the number of times 313.
Note that the eigennumber 312 is a source of the number of calculations created by being calculated together with the number of times 213 in the reading apparatus 200, and is set as appropriate by setting means (not shown) such as a button of the receiving apparatus 300. It is a numerical value that can be.

The collation unit 320 determines whether the ID, the number of restorations (described later in detail) and the number of times received from the reading device 200 match the ID 311, the unique number 312 and the number of times 313 stored in the storage unit 310. The function is performed by the CPU, for example.
The numerical value updating unit 330 updates the number of times 313 stored in the storage unit 310 every time it recognizes the use of the key medium 100 (for example, 1 is added), and it is a unique number at a predetermined timing (for example, once a day). 312 is updated (for example, 1 is added), and the function is performed by the CPU, for example.
The communication unit 340 is a device that relays communication between the verification unit 320 and the reading device 200, and is, for example, a wired communication interface.

(Operation)
Next, the operation of the verification system 1 according to the present embodiment will be described with reference to FIG. 3 (see FIG. 1 as appropriate).
FIG. 3 is a flowchart showing a flow of operations of the key medium, the reading device, and the receiving device. Hereinafter, the operation will be described in detail by dividing it into a preparatory preparatory operation and a collation operation.

<Preparation operation>
The preparatory operation before collation of the collation system 1 is that when the previous collation result is good, the total number (calculation number) for the next collation is transmitted from the receiving device 300 to the key medium 100 via the reading device 200. This corresponds to S1 (abbreviation of step 1; the same applies hereinafter) to S4 in the flowchart of FIG.
First, immediately after the previous verification, the communication unit 340 of the receiving device 300 transmits the unique number 312 (for example, 405) and the number of times 313 (for example, 16) in the storage unit 310 to the reading device 200 (S1).
The information transmission in S1 is realized by transmitting the information current 43 shown in FIG. 2A from the communication unit 340 of the reception device 300 to the second communication unit 240 of the reading device 200, for example. FIG. 2A is a schematic diagram showing a state in which information is converted into a current value, and information is expressed by an information current 43.
The information current 43 is an alternating current, and how far the current value peak (timing l, m, n) value differs from the current value peak value (timing l, m, n) of the reference current 42. Can express information. In this case, if the value at the current value peak (timing l, m, n) is h to d (A), information “0”, if d to e (A) or i to h (A), information “1”, If e to f (A) or j to i (A), information "2" is indicated. If f to g (A) or k to j (A), information "3" is indicated. That is, the timing l represents the information “3”, the timing m represents the information “2”, and the timing n represents the information “1”.

Although the information is expressed as a quaternary number here, other information such as a binary number or a quinary number can be similarly expressed.
Further, the eigennumber may be a larger number for increasing the security level, or may be a smaller number for reducing the processing load in the collation system 1, and is appropriately set to a convenient numerical value. be able to. The number of times may be the actual number of times the key medium 100 is used, but is not limited thereto, and a larger numerical value (for example, 123456) may be used to increase the security level.

Returning to the flowchart of FIG. 3, the processing unit 220 of the reading apparatus 200 that has received the eigennumber (405) and the number of times (16) via the second communication unit 240 then stores the number of times (16) in the storage unit 210. This is stored as 213 (S2). In S2, the eigennumber (405) is also temporarily stored as the eigennumber 212 in the storage unit 210, but may be deleted after the next calculation in S3.
Next, the processing unit 220 of the reading apparatus 200 adds the eigennumber 212 (405) and the number of times 213 (16) to create a total number (421) (S3).
In S3, more complicated operations such as four arithmetic operations such as subtraction or addition of the square of the number of times to the eigennumber may be performed instead of addition. In this case, the numerical value created as a result of the calculation is called the calculation number. In that case, the calculation number is stored in the total number 112 of the key medium 100 in the next S4.
Subsequently, the processing unit 220 of the reading device 200 transmits the total number (421) to the key medium 100 via the first communication unit 230 (S4), and the storage unit 110 of the key medium 100 receives the total number (421). Is stored as the total number 112.

  In this way, by storing only the total number (the number of operations) in the key medium 100, even if the data in the key medium 100 is illegally read, the data can be used. Even if it exists, it is only once immediately after that, and the risk of unauthorized access to the verification system 1 can be reduced. Also, if the method for generating the number of operations is complicated, it is difficult to guess the regularity even when the data of the key medium 100 is illegally read several times, and unauthorized access to the verification system 1 is prevented. can do.

<Verification operation>
After the preparation operation is completed as described above, a user of the key medium 100 (hereinafter simply referred to as a user) can perform a collation operation using the key medium 100 at a desired timing. Hereinafter, the collation operation will be described in detail with reference to S5 to S9 in the flowchart of FIG.

First, when the user operates the key medium 100 with respect to the reader 200, the ID 111 and the total number 112 (421) stored in the storage unit 110 of the key medium 100 are transmitted to the reader 200 (S5). . In this case, the communication information can also be transmitted by converting the total number 112 into the time length of all or part of the communication information. The specific means will be described later.
The processing unit 220 of the reading apparatus 200 that has received the ID and the total number (421) determines whether the ID is valid depending on whether or not the received ID matches the ID 211 stored in the storage unit 210. It is determined whether or not (S6).
When it is determined that the ID is not valid (No in S6), the reading device 200 ends the process. In this case, the reader 200 may notify the key medium 100 or the receiver 300 that the verification result is defective. In this case, the key medium 100 and the receiving device 300 may store the received verification result failure.

  When it is determined that the ID is valid (Yes in S6), the processing unit 220 of the reading device 200 subtracts the number of times 213 (16) stored in the storage unit 210 from the total number received (421) ( S7), a subtraction number (405) is created. Note that when an operation other than addition is performed in S3, in S7, an operation that should be able to create the original eigennumber (405) (inverse operation of S3) is performed instead of subtraction. . In this case, a numerical value created by the calculation is called a restoration number.

Next, the processing unit 220 of the reading device 200 transmits the ID 211 and the number of times 213 (16) stored in the storage unit 210 and the subtraction number (405) created in S7 to the receiving device 300 (S8). .
The information transmission in S8 is realized by transmitting, for example, a current having the information voltage shown in FIG. 2B from the second communication unit 240 of the reading device 200 to the communication unit 340 of the receiving device 300. . FIG. 2B is a schematic diagram showing a state in which information is converted into voltage, and information is converted into a current having an information voltage 41.

The information voltage 41 is information “0” when it is a reference voltage, information “1” when it is higher than the reference voltage by a predetermined voltage, and information “2” when it is twice the reference voltage higher than the reference voltage. When the reference voltage is three times higher than the reference voltage, information “3” is indicated.
Although the information is expressed as a quaternary number here, other information such as a binary number or a quinary number can be similarly expressed. Further, not only the case where the voltage is higher than the reference voltage but also the case where the voltage is lower than the reference voltage may be used as information representation.

The information transmission in S8 will be described in more detail with reference to FIG. FIG. 2C is a schematic diagram showing a state in which ID, subtraction number (operation number), and number of times are converted to voltage. In the information voltage 44, an ID and a subtraction number (operation number) are expressed in the first predetermined time length (timing p to q). In this case, the portion of the information voltage 44 is expressed by a binary number of information “0” when the reference voltage is 12V, and information “1” when the reference voltage is 13V. This is the same as in FIG.
In the information voltage 44, the number of times is expressed by the length of time that is 11V from the timing q. That is, in this case, for example, if 0.05 (second) is defined as one time, 16 times can be expressed as 16 × 0.05 (second) = 0.8 (second).
Note that the time length for one time may not be 0.05 (seconds) but may be another length such as 0.04 (seconds). Further, the range of the portion expressing the number of times may be limited to a predetermined time length (for example, 2.00 seconds) from timing q.
In addition, the part expressing the number of times may not be after the part expressing the ID or the subtraction number (the number of operations), or may be before it.

Conventionally, information on an IC card (corresponding to the key medium 100) is read by a card reader (corresponding to the reading device 200) and collation is performed, and when the collation result is good, a control device (receiving device) such as an electric lock from the card reader. In a verification system that transmits an ON / OFF-only control signal or contact signal to an equivalent to 300), a malicious person transmits a control signal for unauthorized access from an unauthorized device to the control device to perform an unauthorized operation of the control device. Was also relatively easy.
However, as described above, according to the verification system 1, information transmission from the reading device 200 to the receiving device 300 is performed by a current obtained by converting information into voltage, and the number of times is different from that of other information. By expressing in length, if a malicious person tries to intercept information from the communication line between the reading device 200 and the receiving device 300 or tries to send information for unauthorized access from the unauthorized device to the receiving device 300 Even in such a case, it can be difficult to realize them.

  In S5, the total number 112 may be converted into the time length of all or part of the transmission time of the communication information, and the communication information may be transmitted in the same manner as in FIG. That is, when communication is performed from the key medium 100 to the reading device 200, the total number 112 is set to one piece of communication information in the key medium 100, for example, in the same way that 0.8 seconds represents the number of times in FIG. It can be expressed as the transmission time of the part, and the communication information may be transmitted. Similarly, the total number 112 can be expressed not as a part of the communication information but as a time length of the entire transmission time. At that time, the reading device 200 obtains the time length representing the total number 112 in the communication information from the length of time that the values of voltage, current, impedance, electromagnetic wave (infrared rays, etc.) are equal to or greater than the threshold value. So that the total number 112 can be recognized.

Returning to the flowchart of FIG. 3, after S8, the collation unit 320 of the receiving device 300 that has received the ID, the number of times (16), and the subtraction number (405) determines that the number of times of reception (16) and the subtraction number (405) are Collation is performed by determining whether or not the ID 311, the number of times 313, and the unique number 312 stored in the storage unit 310 match (S 9). Although not shown, if the collation result is good, the receiving apparatus 300 performs control such as unlocking the electric lock.
Further, although not shown in FIG. 3, for the next use of the key medium 100, the receiving apparatus 300 transfers to the key medium 100 via the reading apparatus 200 in the same procedure as S <b> 1 to S <b> 4 in FIG. 3. The total number (422) based on the unique number (405) and the number of times (17: a value obtained by adding 1 to 16 by the numerical value updating unit 330) is registered. At that time, the value of the unique number 312 may also be changed, and the total number (423) of the unique number (406) and the number of times (17) may be registered in the storage unit 112 of the key medium 100.

As described above, according to the collation system 1 according to the present embodiment, the key medium 100 is collated with respect to the key medium 100 by using not only the ID that is invariant information but also the number of times (information) that is variable information. Even if the information is stolen, it is possible to achieve a high security level that makes unauthorized access difficult.
In addition, when communication information is transmitted from the key medium 100 to the verification device, the number of computations is converted into the length of the transmission time of all or part of the communication information and transmitted, so that unauthorized access by decrypting the communication information is performed. Can be made more difficult.
Furthermore, by using the number of operations calculated / created based on the number of times (information) and the eigennumber for verification, it becomes more difficult to decrypt when the information of the key medium 100 is stolen, and a higher security level is obtained. Can be realized.
Further, a higher security level can be realized by changing the unique number at a predetermined timing.
Further, when information is transmitted from the reading apparatus 200 to the receiving apparatus 300, the possibility of unauthorized access to the receiving apparatus 300 or the like can be reduced by converting the number of times (information) into a time length with a predetermined voltage added. it can.

This is the end of the description of the embodiments, but the aspects of the present invention are not limited to these. For example, if the present invention is used for hotel entrance / exit management, the information used for verification changes every time. Therefore, even if a malicious person illegally reads (copies) the information on the key medium, the administrator returns it. Once the key medium is operated once, a malicious person cannot use the information, and the registration work of the key medium is not required every time the user changes. In such a case, even if the key medium is lost, the lost key medium cannot be used by performing a single operation with the newly created key, and there is no need to delete the registration. Media management can be realized.
Further, the present invention can be applied not only to entrance / exit management of buildings but also to use / management of vehicles and equipment (for example, vehicle immobilizer). In addition, about a concrete structure, it can change suitably in the range which does not deviate from the main point of this invention.

It is a whole block diagram of a collation system. (A) It is the schematic diagram showing the mode at the time of converting information into an electric current value. (B) It is the schematic diagram showing the mode at the time of converting information into voltage. (C) It is the schematic diagram showing the mode at the time of converting ID, a subtraction number (the number of calculation), and a frequency | count into voltage. It is the flowchart which showed the flow of operation | movement of the collation system.

Explanation of symbols

100 key medium 110 storage unit (key medium storage unit)
120 communication unit 200 reading device 210 storage unit (reading device storage unit)
220 processing unit (reading device processing unit)
230 1st communication part 240 2nd communication part (reading device communication part)
300 Receiving Device 310 Storage Unit (Receiving Device Storage Unit)
320 Verification unit (receiving device processing unit)
330 Numeric Updater 340 Communication Unit

Claims (4)

A verification system in which a verification device reads information stored in a key medium and performs verification,
The verification device includes an ID of the key medium, a unique number used for calculation corresponding to the ID, a verification device storage unit that stores the number of times the key medium has been used, the unique number, and the number of times. And a verification device processing unit that creates the number of operations from the operation based on
The key medium has a key medium storage unit that stores the ID and the number of operations received from the verification device;
The verification device processing unit receives the ID and the number of operations from the key medium, and from the calculation based on the received number of operations and the number of times corresponding to the ID stored in the verification device storage unit A collation system characterized in that a restoration number is created and a collation is determined based on whether or not the restoration number matches the eigennumber. A verification system in which a verification device reads information stored in a key medium and performs verification,
The verification device includes an ID of the key medium, a unique number used for calculation corresponding to the ID, a verification device storage unit that stores the number of times the key medium has been used, the unique number, and the number of times. A verification device processing unit that creates the number of operations from the operation based on
The key medium includes a key medium storage unit that stores the ID and the number of calculations received from the verification device, and the number of calculations for the transmission time of all or part of the communication information including the ID. A key medium communication unit that converts the information into a length and transmits communication information to the verification device,
The verification device processing unit recognizes the calculation number from the time length of all or part of the communication information received from the key medium communication unit, and stores the calculation number and the verification device storage unit. A collation system, wherein a restoration number is created from an operation based on the number of times corresponding to the ID, and collation is determined based on whether or not the restoration number matches the eigennumber.   The collation system according to claim 1, wherein the collation device processing unit changes the eigennumber stored in the collation device storage unit at a predetermined timing. A verification system in which information held by a key medium is read by a reading device, and the receiving device performs verification by using information received from the reading device,
The receiving device includes a receiving device storage unit that stores an ID of the key medium, a unique number corresponding to the ID and used for calculation, and the number of times the key medium has been used, and a receiving device process for performing calculation processing. Part
The reader includes a reader storage unit that stores the ID, the unique number, and the number of times, a reader processing unit that creates a calculation number from a calculation based on the unique number and the number of times, and the reception device. A reader communication unit for communicating information;
The key medium includes a key medium storage unit that stores the ID and the number of operations received from the reading device;
When collation is performed by the key medium, the reader, and the receiver, the reader processor is based on the number of times stored in the reader storage and the number of operations received from the key medium. The restoration number is created from the calculation, and when the reader communication unit sends the ID, the restoration number, and the number of times to the receiving device, the number of times is converted into a time length with a predetermined voltage and transmitted, The receiving device processing unit makes a matching determination based on whether or not the received restoration number and the number of times coincide with the eigennumber and the number of times stored in the receiving device storage unit. .

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