JP2006059228A - Storage device and data management system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a storage device and a data management system capable of surely erasing, at the occurrence of a specific event, such data that is removed from a predetermined information processor and is temporarily stored. <P>SOLUTION: Data fetched from a personal computer through a USB terminal 102 is stored in a RAM 113 as a volatile memory. A timer section 115, after time selected by a user has elapsed, halts refreshing of the RAM 113 with respect to a refresh circuit 117. Thereby, data and a user's code number used for encryption are all completely erased. Even when an abnormal state such as the disassembly of the storage device 101 occurs, power supply to the RAM 113 is shut off and the data is erased. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a storage device having a memory for storing data and a data management system for managing leakage prevention of data stored in the memory.

  Storage media such as various memories, or data storage devices incorporating these (hereinafter collectively referred to as storage devices) are evolving steadily, increasing the capacity of stored data and downsizing the devices. Realized. On the other hand, troubles in which data stored in the storage device leaks frequently occur due to inadequate memory management, which is a social problem. As the amount of data that can be stored increases, the amount of data that flows out at one time also increases.

  Therefore, the previous use date and time of the storage device is stored, and if the preset set time has elapsed from this use date and time, the storage device is assumed to have passed to a third party, A first proposal has been made to execute security processing that prohibits use or prevents information leakage (see, for example, Patent Document 1). Specifically, when it is determined that the set time has elapsed, the application software is set to an inexecutable state, the display screen is set to an incapable display state, or the power cannot be turned on. It is set to a state, or a key input is set to an impossible state.

  However, in the first proposal, the security process is executed for the device including the storage device. Therefore, for example, if the storage device is taken out from the incorporated device and incorporated in another device such as a third party, data can be freely read from the incorporated storage device and used.

  Therefore, a proposal has been made to detect unauthorized access to a storage device by a third party, generate a power stop signal according to the detection result, and stop the supply of power to the storage device (for example, a patent). Reference 2). In the second proposal, an illegal access to the storage device is detected by monitoring a memory reference request on the memory bus. When unauthorized access occurs a predetermined number of times, a power supply stop request is generated for the storage device, and the power supply is turned off. As a result, if the storage device uses a volatile memory, its contents are erased.

  However, this second proposal requires a special circuit for reliably detecting unauthorized access to the storage device. This is because a non-illegal access should not be erased by determining it as an unauthorized access. For this reason, not only is the cost for the special circuit increased, but the power cannot be turned off as the unauthorized access actually occurs until the unauthorized access occurs a predetermined number of times. Therefore, in the case where illegal access actually occurs continuously, unauthorized access is permitted until a predetermined number of times is reached, and data leakage is allowed to some extent. Therefore, there is a problem that management of data leakage prevention becomes incomplete.

  In order to solve this problem, a third proposal is made in which the information in the memory is erased when a preset time has passed by the microprocessor by using the timed function in consideration of the first proposal. (For example, refer to Patent Document 3). There is also a proposal to monitor the timer value set in the initial state and delete specific data stored in the memory under the control of the microprocessor after a certain time corresponding to the timer value has elapsed. (For example, refer to Patent Document 4).

Of these, in the third proposal, a microprocessor is used to control data erasure with the passage of time. In the fourth proposal, the timer value is monitored, and when the timer value has passed a certain time, the specific data in the memory containing the battery is deleted.
JP 2001-117824 (paragraph 0005, FIG. 5) JP-A-4-199246 (second page, lower right column, 14th line to third page, upper left column, 19th line, FIG. 1) JP 63-54294 A (the second page, lower right column, lines 6 to 9) JP 62-287388 A (9, 10 paragraphs of claims)

  However, in the third proposal, since the microprocessor erases the information in the memory in a predetermined procedure, there is a possibility that the data stored in the memory is not erased if any failure occurs in the erase procedure. In the fourth proposal, the memory is composed of an IC (integrated circuit) card and includes a built-in battery. The built-in battery supplies specific data when a predetermined time elapses when power is supplied to the IC card instead of this external power supply when power is no longer supplied from the external power supply of the device or the like to which the IC card is attached. Is supposed to be erased. Therefore, also in the fourth proposal, the microprocessor needs to cut off the power supply in accordance with a predetermined procedure.

  As described above, in the fourth proposal, as in the third proposal, in the erase control of the data in the memory, the microprocessor itself executes the erase control procedure. Therefore, there is a problem that data may not be erased from the storage device if any abnormality occurs in the microprocessor itself or in the erase control procedure.

  Accordingly, an object of the present invention is to provide a storage device and a data management system capable of reliably erasing data that is removed from a predetermined information processing apparatus and temporarily stored when a specific event occurs. is there.

  (1) Volatile memory for storing data and (b) Volatilization for preventing volatilization while consuming electric energy so that the data stored in this memory does not volatilize and disappear. And (c) a power source for supplying electric energy for preventing volatilization to the volatilization preventing unit, and (d) electricity for interrupting the supply of electric energy to the volatilization preventing unit when a specific event occurs. Energy storage blocking means is provided in the storage device.

  That is, according to the first aspect of the present invention, a volatile memory is used for data storage, and volatilization prevention means is used to prevent volatilization while consuming electric energy so that the data is not volatilized and lost. When the time limit for retaining the data has expired or when a specific event that causes a security problem occurs, the supply of electrical energy to the volatilization prevention means is shut off by the electrical energy supply prevention means. In this way, data is actively deleted. This erasure is realized simply by shutting off the supply of electrical energy to the volatilization prevention means, so that the data can be erased easily and reliably.

  According to the second aspect of the present invention, (b) a random access memory for storing data, and (b) an electric energy supply means for supplying electric energy so that the data stored in the random access memory is not lost. And (c) electrical energy supply blocking means for cutting off the supply of electrical energy to the random access memory by the electrical energy supply means when a specific event occurs.

  That is, according to the second aspect of the present invention, a random access memory as a volatile memory is used for data storage, and the electric energy supply means prevents the data stored in the random access memory from being lost. Energy is supplied. Then, when the time limit for retaining the data has expired or when a specific event occurs that causes a security problem, the electrical energy supply means prevents the electrical energy from being supplied to the random access memory. It is decided to actively erase the data by cutting off the supply of energy. This erasure is realized simply by cutting off the supply of electrical energy to the random access memory, so that the data can be easily and reliably erased.

  In the invention according to claim 5, the data management system includes (a) the storage device according to any one of claims 1 to 4 and (b) an information processing device for storing data in the storage device.

  That is, in the invention according to claim 5, by configuring a data management system with the storage device according to any one of claims 1 to 4 and the information processing device that stores data in the storage device, The risk of leakage of data stored in the storage device to a third party is avoided.

  As described above, according to the present invention, data to be considered for security is stored in a volatile memory such as a random access memory in a storage device, and is retained using electric energy. Therefore, when a specific event occurs, the data can be completely erased from the memory by a simple method of cutting off the supply of electrical energy. Therefore, the reliability of data erasure can be improved as compared with the conventional method in which the data erasure process using a program is realized by overwriting invalid data, for example.

  In addition, since a method of cutting off the supply of electrical energy to the volatile memory is adopted, the data is actively transferred when an abnormality such as decomposition of the storage device occurs by adding a simple mechanism or the like. By erasing, the risk of data leakage can be avoided.

  Hereinafter, the present invention will be described in detail with reference to examples.

  FIG. 1 shows an outline of a data management system in an embodiment of the present invention. The data management system 100 includes a storage device 101 and a personal computer 104 including a USB terminal connection unit 103 that connects a USB (Universal Serial Bus) terminal 102 provided in the storage device 101.

  FIG. 2 shows the configuration of the storage device. The storage device 101 includes an external interface (IF) unit 111 connected to the USB terminal 102 and a RAM (random access) that inputs and outputs data 112 to and from the personal computer 104 shown in FIG. A memory) 113, which is also connected to the personal computer 104 via the external interface unit 111, a timer unit 115 that inputs a timer setting signal 114 to set a timer value, and an internal power source 116 that supplies power to the RAM 113. It has. A large capacity RAM 113 is prepared according to the price of the storage device 101.

  For example, the internal power supply 116 includes a rechargeable battery as a secondary battery and a charger that charges the rechargeable battery 102 using a DC power supply obtained from the USB terminal 102. Of course, the above-described rechargeable battery may be charged from the outside using a commercial power source such as 100 volts without going through the USB terminal 102. The internal power supply 116 supplies power to the refresh circuit 117 and periodically refreshes the RAM 113 with a refresh signal 118 output from now. The timer unit 115 supplies a refresh request signal 119 to the refresh circuit 117 until the set time has come.

  By using the RAM 113 as a volatile storage medium in this way, the stored data is erased when the refresh signal 118 is no longer supplied thereto. In the storage device 101 of the present embodiment, for data erasure, a first method in which the refresh signal 118 for supplying electrical energy to a volatile storage medium is mechanically interrupted, and supply of electrical energy by the electrical signal By adopting two methods of the second method for blocking the data, a mechanism is realized in which the data stored in the storage device 101 is erased in a predetermined case.

  FIG. 3 shows a mechanical mechanism for erasing data in this embodiment. The storage device 101 includes a bowl-shaped case main body 131 formed of a resin and a lid portion 132 made of a flat plate resin that covers an opening of the case main body 131. The lid portion 132 is fixed to the case main body 131 by a metal screw 133. At the location of the cylindrical hole 136 into which the threaded portion 133A of the metal screw 133 in the case body 131 is screwed, the inner surfaces of the pair of conductive rings 134 and 135 are in contact with the inner surface of the hole. So that it is pre-molded. These conductive rings 134 and 135 are made of, for example, a soft metal such as lead or a conductive rubber material, and are arranged at a predetermined interval, and each has a separate lead wire 137, 138.

  One lead wire 137 has its end connected to the internal power supply 116 shown in FIG. 2, and the other lead wire 138 has its end connected to the refresh circuit 117. Therefore, when the metal screw 133 is screwed into the hole 136, the conductive rings 134 and 135 are electrically connected, and the power is supplied from the internal power supply 116 to the refresh circuit 117 by the lead wires 137 and 138. .

  Assume that data is stored in the RAM 113 shown in FIG. 2, and the refresh circuit 117 performs the refresh operation. At this time, it is assumed that someone tries to remove the metal screw 133 in order to remove the lid 132 fixed to the case main body 131 of the storage device. As a result, when the screw part 133A of the metal screw moves in the direction opposite to the screwed direction, the conductive ring 135 is first brought into non-contact with the screw part 133A, and at this time, the power supply to the refresh circuit 117 is not supplied. Refused. Accordingly, all data stored in the RAM 113 is erased at this point. That is, when someone tries to disassemble the storage device 101, all the data stored in the threaded portion 133A is erased when the threaded portion 133A stops physical contact with at least one of the pair of conductive rings 134 and 135. Will be. Thereby, there is no risk that the data stored in the RAM 113 is leaked to a third party.

  In order to detect the decomposition of the storage device 101, various known techniques can be applied. For example, if a magnetic sensor (not shown) is arranged in the case body 131 and a magnet is arranged at a corresponding position in the lid portion 132, the magnetic sensor will not detect magnetism when the lid portion 132 is opened. Thus, the supply of power to the refresh circuit 117 can be cut off, or the refresh signal 118 supplied from the refresh circuit 117 to the RAM 113 can be cut off.

  Similarly, using an optical sensor, for example, checking for the presence of external light at a rate of once every few minutes, the lid 132 is opened or a hole is formed in a part of the case body 131. In this case, this may be detected.

  FIG. 4 shows still another method for detecting the removal of the lid and erasing the data stored in the RAM. The other end of the lead wire 137 whose one end is connected to the internal power supply 116 shown in FIG. 2 is connected to the male terminal 142 fitted to the female terminal 141, and the female terminal 141 connects one end to the refresh circuit 117. The other end of the lead wire 138 is connected. After all the adjustment of the circuit of the storage device 101 is completed with the female terminal 141 and the male terminal 142 connected, either one of the lead wires 137 and 138 is connected with some tension on both the lead wires 137 and 138. The lid 132 is fixed to the case body 131 so as to be fixed to the inner surface of the lid 132 (FIG. 3) with an adhesive or an adhesive tape.

  In this way, when someone opens the lid 132, a pulling force acts between the lead wires 137 and 138, and the female terminal 141 and the male terminal 142 are separated. As a result, the data stored in the RAM 113 can be erased as in the mechanical mechanism shown in FIG.

  Next, electrical data erasure using the timer unit 115 will be described. The storage device 101 of this embodiment is configured to set a time as a timer by a personal computer 104 (see FIG. 1) that uses this as an external storage device. When the set time arrives, the output of the refresh request signal 119 is stopped, whereby the data stored in the RAM 113 is erased all at once. When the time until data is erased is managed by the timer unit 115 shown in FIG. 2, a display made of liquid crystal or the like is arranged in the timer unit 115 as described below, and the remaining time May be displayed.

  FIG. 5 shows the external appearance of the storage device of this embodiment provided with a liquid crystal display. In this embodiment, a liquid crystal display 151 is arranged on the case body 131 side of the storage device 101, and the time until data is erased all at once (in this example, 3 hours and 25 minutes) is displayed. It has come to be. An authorized user of the storage device 101 can change the time by connecting the storage device 101 to the personal computer 104 before this time elapses. In addition, when storing data in the storage device 101, the user designates the time until the data is erased and, if necessary, the data to be erased, or sets a preset default value. To be adopted.

  In addition, in order to perform such control related to data erasure management, application software (hereinafter abbreviated as management software) corresponding to data management of the storage device 101 is stored in advance on the personal computer 104 side. It has become. Therefore, even if the storage device 101 is connected to a personal computer that does not store management software corresponding to the storage device 101, the time until the data is erased cannot be updated. Cannot be read and used.

  FIG. 6 shows an outline of processing of management software stored in the personal computer when the storage device is connected. When the storage device 101 is connected to the personal computer 104 via the USB terminal 102, a CPU (central processing unit) (not shown) in the personal computer 104 determines whether a new storage device is connected (step S201). If the storage device 101 is not in a predetermined format, it is regarded as a new storage device 101 (Y).

  In the case of the new storage device 101, an inquiry as to whether or not the storage device 101 can be formatted is displayed on the display of the personal computer 104 (step S202). When the user inputs a response indicating that the format is possible (Y), the format corresponding to the storage device 101 is executed (step S203). In this format, the user is requested to input a personal identification number. The user can appropriately change the password every time formatting is performed. Of course, the user needs to remember the set password.

  On the other hand, if the user designates that formatting is impossible in step S202 (N), a storage device that is not originally intended for the management software is connected to the personal computer 104. Therefore, in this case, an error is displayed on the display of the personal computer 104 (step S204), and the processing by the management software ends (END).

  When the storage device 101 that has already been formatted is connected to the personal computer 104 (step S201: N), the user is requested to input a personal identification number (step S205). At this time, it is not necessary to read the remaining time as the time for holding data from the timer unit 115 of the storage device 101 and determine whether it is within the remaining time. This is because when the remaining time becomes zero, the storage device 101 of this embodiment completely erases the contents of the RAM 113, so that it is determined as a new storage device 101.

  When the user inputs the password requested in step S205, the personal computer 104 compares it with the password set by the user in step S203. If the passwords match (step S206: Y), various processes desired by the user are executed (step S207) as will be described later.

  When the personal identification number entered by the user does not match the personal identification number stored in the personal computer 104 at the time of formatting (step S206: N), it is checked whether the personal identification number is within the allowable number of times of input. Is performed (step S208). If the number is within the allowable number, the numerical value “1” is added to the number m of input of the personal identification number (step S209), and the process again proceeds to step S205 to request the user to input the personal identification number.

  On the other hand, if it is determined in step S208 that the allowable number has been exceeded (step S208: N), there is a high possibility that a person who is not a regular user has been impersonated as a user. Therefore, in this case, the process proceeds to step S204, an error display is performed, and the process ends (END).

  FIG. 7 specifically shows the contents of various processes shown in step S207 of FIG. Here, the CPU described above determines whether the process requested by the user is data storage in the storage device 101 (step S221), data read from the storage device 101 (step S222), or the user's own process. It is determined whether or not the data is erased from the storage device 101 at will (step S223). If it is not any processing (step S223: N), the remaining time at the present time is calculated based on the remaining time read from the storage device 101 at the time of connection or the remaining time calculated based on the time set in the storage device 101. The process of notifying the storage device 101 is repeated at predetermined intervals (step S224).

  As described above, in this embodiment, the personal computer 104 notifies the remaining time in a state where the storage device 101 is connected to the personal computer 104, so that no time management error occurs between the two. Yes. Note that, unlike the present embodiment, while the storage device 101 is connected to the regular personal computer 104, the remaining time is stopped, or the remaining time is set to a default value or a remaining time set in advance by the user. It is also possible to reset to the initial value (life).

  Incidentally, when the user selects to store the data stored in the personal computer 104 or the like in the storage device 101 of this embodiment (step S221: Y), first, the data to be stored is designated (step S221). S225). The CPU checks whether or not the designated data can be stored in the storage device 101 (step S226). If the amount of data that can be stored is exceeded (N), it is determined whether or not the amount or number of data stored by the user is to be changed (step S227). If the change is not made (N), the data cannot be stored in the storage device 101, so the process proceeds to step S204 in FIG. 6 to display an end due to an error. In the case of changing (step S227: Y), the data to be stored is redesignated (step S225), and the processing after step S226 is performed.

  By the way, if it is determined in step S226 that the data selected by the user can be stored in the storage device 101 (step S226: Y), is the user setting the lifetime in the storage device 101? It is determined whether or not (step S228). In the case where the lifetime is particularly lengthened or shortened depending on the type of data, the user designates the lifetime. In such a case (Y), the life input by the user is set as the life in the storage device 101 (step S229). In other cases (step S228: N), a default value prepared in advance is set as the life (step S230).

  When the data lifetime in the storage device 101 is set as described above, the setting value is transmitted from the personal computer 104 to the storage device 101 (step S231). Then, the corresponding data is encrypted based on the password set by the user (step S232). As described above, each time the storage device 101 is formatted, the user can change the personal identification number. Therefore, every time data is newly stored in the storage device 101, even if it is the same data, the data content after encryption can be changed, and the security of the data can be improved.

  The encrypted data is sent from the personal computer 104 to the storage device 101 via the USB terminal 102 (step S233). In this way, the encrypted data is stored in the RAM 113 of the storage device 101.

  On the other hand, when the user selects to read data from the storage device 101 (step S222: Y), the encrypted data is read from the storage device 101 (step S234). Therefore, even if the data in the storage device 101 is read from a computer on which no management software is installed, it is very difficult to decrypt the data into the original data. Also, when a user of another computer that has installed the same management software reads this data, a unique number is registered for each owner of the management software, and encryption is set by this unique number and the user's settings. If the processing is performed with the combination of the passwords, it is difficult to decrypt the data. Of course, in this embodiment, since a method of erasing data in a predetermined case is employed, the security of data stored in the storage device 101 is extremely high.

  Next, a case where the user selects to voluntarily delete the data in the storage device 101 in step S223 will be described. In this case (Y), the corresponding data is deleted from the storage device 101 in the same manner as the personal computer 104 deletes the data from the normal external storage device (step S235).

  FIG. 8 shows an outline of processing when the storage device is removed from the personal computer in this embodiment. The storage device 101 includes a CPU (not shown) and a ROM (Read Only Memory) that stores a control program. Then, it is periodically checked whether or not the USB terminal 102 is extracted from the USB terminal connection unit 103 shown in FIG. 1 (step S241). When the USB terminal 102 is extracted from the USB terminal connection unit 103 (Y), It is checked whether data is stored in the RAM 113 (step S242). If there is no data (N), there is no need to perform further processing. Therefore, in this case, the processing is ended until the USB terminal 102 is connected to the USB terminal connection unit 103 again and power is supplied (end).

  On the other hand, if data is stored in the RAM 113 (step S242: Y), the latest one of the remaining times sequentially notified from the personal computer 104 in step S224 in FIG. 7 is displayed on the liquid crystal display 151 (see FIG. 7). Step S243). Therefore, the user can check the remaining time at this point.

  Thereafter, the storage device 101 subtracts the remaining time with the passage of time and displays the value on the liquid crystal display 151 (step S244). The subtraction and remaining time display processes are continued until the remaining time becomes zero (step S245: N). When the remaining time becomes zero (step S245: Y), the CPU stops supplying the refresh request signal 119 to the refresh circuit 117, and erases the data and password stored in the RAM 113 (step S246). Thereafter, the CPU ends the process until the USB terminal 102 is connected to the USB terminal connection unit 103 again and power is supplied (end).

  As described above, according to the present embodiment, for the data stored in the storage device 101 connected to the personal computer 104 via the USB terminal, the remaining time is actively managed according to the user's will, and the remaining time is When it became zero, not only the data but also the password was deleted. Thus, even if a malicious third party temporarily removes the storage device 101 from the personal computer, analyzes it, connects it to the original personal computer, and prepares to read the next stored data, When the user sequentially changes the password, the security level of encryption combined with the password is not lowered.

  In addition, since the RAM as the volatile memory is used in the present embodiment, all the data stored in the RAM is surely erased by disconnecting the power supply when the apparatus is disassembled or some trouble occurs. can do.

  Furthermore, in this embodiment, dedicated application software (management software) for managing the storage device 101 is installed in the personal computer 104 to which the storage device 101 is connected. This makes it possible to actively manage the remaining time according to the importance of the data and the like, unlike the conventional technique in which a timer preset in the storage device itself performs uniform time management. Further, since the storage device 101 itself has a function of erasing data independently even if the personal computer 104 as the parent device does not directly delete the data in the storage device 101, the storage device after being removed from the personal computer 104 The security of the data 101 can be ensured.

  <Deformability of invention>

  In the embodiment described above, the storage device is connected to various information processing apparatuses represented by a personal computer via the USB terminal. However, the connection means is not limited to the USB terminal. . For example, it may be connected by PCMCIA (Personal Computer Memory Card International Association) or SCSI (Small Computer System Interface).

  In addition, the RAM for storing data according to the present invention is of course applicable to all storage media in which normal storage of data cannot be maintained by stopping or preventing the supply of power. Therefore, for example, an optical disk used in combination with a cooling device as a volatilization prevention means for preventing volatilization while consuming electric energy under the premise that it is always used in a high temperature environment is also cut off in power supply. In an environment where the data stored on the optical disk cannot be held in a normal state, the RAM as the volatile memory referred to in the present invention is used.

  Next, in this embodiment, data as one management target is stored in one RAM 113, but the present invention is not limited to this. For example, multiple units of data may be managed by setting the remaining time independently. At this time, the RAM and the power supply path for these may be separated for each unit data. In addition, when an abnormality occurs when the storage device is disassembled or the like, the data security can be ensured by erasing these plural units of data at once.

  Of course, the storage device of the present invention does not have to be composed of a RAM as a volatile memory. For example, a memory that stores data related to the owner of a storage device or data that is not subject to security, such that the data can be maintained normally even if the power supply is cut off. Of course, it may be included.

  In the embodiment, the storage device 101 itself has a simple configuration in which only the liquid crystal display 151 is arranged. However, an erase key may be attached to the storage device 101. Thus, the user can easily erase the built-in data without having to bother to connect the storage device 101 to the personal computer 104. In this case, a device such as a switch for protecting erasure may be added.

1 is a system configuration diagram showing an outline of a data management system in an embodiment of the present invention. It is a block diagram of the memory | storage device of a present Example. It is principal part sectional drawing of the memory | storage device in a present Example. It is explanatory drawing which showed methods other than the Example which erase | eliminates the data stored in RAM. It is the top view which showed the external appearance of the memory | storage device of a present Example. It is a flowchart which shows the process of a personal computer when a memory | storage device is connected. It is a flowchart which expressed the contents of various processing concretely. It is a flowchart which shows the outline | summary of a process when a memory | storage device is removed from a personal computer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Data management system 101 Memory | storage device 102 USB terminal 103 USB terminal connection part 104 Personal computer 113 RAM
115 Timer part 116 Internal power supply 119 Refresh request signal 133 Metal screw 133A Screw part 134, 135 Conductive ring 137, 138 Lead wire 141 Female terminal 142 Male terminal

Claims (7)

Volatile memory for storing data,
Volatilization prevention means for preventing volatilization while consuming electric energy so that data stored in this memory does not volatilize and disappear,
A power source for supplying electric energy for preventing volatilization to the volatilization preventing means;
A storage device comprising: an electrical energy supply blocking unit that blocks supply of electrical energy to the volatilization blocking unit when a specific event occurs. Random access memory to store data;
Electrical energy supply means for supplying electrical energy so that data stored in the random access memory is not lost;
A storage device comprising: an electrical energy supply blocking unit that blocks supply of electrical energy to the random access memory by the electrical energy supply unit when a specific event occurs.   3. The storage device according to claim 2, wherein the electric energy supply means is a refresh circuit or a power supply for supplying electric energy to the refresh circuit. Comprising a disassembly detection means for detecting disassembly of the device;
3. The storage device according to claim 1, wherein the electric energy supply blocking means is means for blocking the supply of electric energy when the decomposition detecting means detects the decomposition of the apparatus. A storage device according to any one of claims 1 to 4;
A data management system comprising an information processing device for storing data in the storage device.   The storage device includes a display for displaying a remaining time as a time during which electric energy for data retention is supplied when a connection for data transfer with the information processing device is disconnected. The data management system according to claim 5.   The information processing apparatus includes a personal identification number setting unit that sets a personal identification number of a user of the storage device that stores data each time new data is stored, and a personal identification number set by the personal identification number setting unit. And encryption means for encrypting data stored in the storage device, and decryption means for decrypting the encrypted data stored in the storage device into the data before encryption when read. The data management system according to claim 5.

Images