JP2009122749A - Program, portable storage medium, and control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To store the update of a system program in a portable storage medium such as a USB memory, and to guarantee that user data do not remain. <P>SOLUTION: This program includes: a step of judging whether or not system data including application data are the latest; a step of interrupting the reception of a user input when it is judged that the system data are not the latest; a step of making an update server acquire the update data of the system data through a network, and execute the update of the system data; a step of, when the completion of the update of the system data is detected, securing snap shot data for restoring a data recording part in which the system data are recorded, and user data may be stored to a state when the update of the system data is completed in the data recording part; and a step of stopping the interruption of the reception of the user input after the snap shot data are secured in the data recording part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a security maintenance technique when a portable storage medium is used.

  The storage capacity of portable storage media such as USB (Universal Serial Bus) memory and portable HDD (Hard Disk Drive) has been increasing year by year, and USB memory is also equipped with tens of gigabytes of flash memory. There are also products. The price is also decreasing, and the use of an application, a virtual machine or the like mounted on such a portable storage medium for operation is spreading.

  In such a situation, an OS (Operating System) image or application (also referred to as a system program. Also, system program data is also referred to as system data) and a user document (also referred to as user data) are stored in the USB memory. For example, it is also possible to use a mixture of documents and program sources created by the user, customer data obtained by the user from the customer, etc., and USB memories with built-in system programs are also available. Has appeared.

  A USB memory or the like is likely to be stolen or lost because it is carried outside, but in order to prevent information leakage at that time, some data in the USB memory is encrypted. In such a product, data in the USB memory can be browsed after successful user authentication. In addition, products that take security into account, such as publishing memory to the host side in cooperation with biometric authentication installed in USB memory, have appeared.

  However, considering the case of use in a company, there is a demand for not storing user data in a USB memory even in an encrypted state.

  For this reason, a system in which only a system program is installed in the USB memory and user data is not saved is possible. However, in this case, the user data created by using the system program must be saved on the local host or saved on a file server at the end of the network. Saving on the local host loses portability and saving on a file server degrades performance.

  Therefore, when the USB memory is used on a PC (Personal Computer), the user data is allowed to be saved in the USB memory. When the USB memory is removed from the PC and the use of the USB memory is terminated, the user data is saved at the time of use. Erase the data that was being saved. Then, when the work is completed, the user saves the data by uploading the created user data to the file server. As a result, the performance does not deteriorate during work, and no user data remains in the USB memory.

  However, the problem has not been completely solved yet. Normally, system programs must be updated. For example, OS update. However, this system program update and user data update cannot be distinguished.

  Specifically, consider a case where an updater, which is a module for updating a system program, updates files A and B, and a word processor application updates files C and D as a program for updating user data. Here, the OS does not recognize that the updater is updating the files A and B of the system program and that the word processor application is updating the user data. The updater recognizes that the system program is being updated, but cannot recognize that other applications (including the word processor application) are updating the files C and D. Similarly, the word processing application recognizes that it is updating user data, but cannot recognize that the updater is updating files A and B of the system program.

  That is, in a system composed of an OS and its process, it is not clear which file is a file for system update and which file is updated by a user, and system program update and user data update cannot be distinguished. . Therefore, it is difficult to automatically save the update of the system program in the USB memory while keeping no user data.

Japanese Patent Laid-Open No. 2003-345600 discloses a system program update method that can update a system program such as a BIOS program without considering the use state of an application program that is running on a personal computer. Specifically, when the rewriting of the BIOS-ROM is completed, the data of the application program activated on the personal computer and the data of the device are stored in the HDD, and the personal computer is turned off. After a predetermined time, the personal computer is turned on and the personal computer is activated. At this time, the application data and device data stored in the HDD before power-off are moved to the main memory. However, it does not solve the problem described above.
JP 2003-345600 A

  Therefore, an object of the present invention is to provide a technique for guaranteeing that no user data remains while a system program update is saved in a portable storage medium such as a USB memory.

  The program according to the first aspect of the present invention includes a step of determining whether the system data including application data is the latest, and accepting a user input when it is determined that the system data is not the latest. The step of blocking, the step of acquiring the update data of the system data from the update server via the network, the step of performing the update of the system data, and the detection of the completion of the update of the system data are recorded. And storing the snapshot data in the data recording unit for restoring the data recording unit in which the user data can be stored to the state when the update of the system data is completed, and the snapshot data is the data recording unit After being secured by the user, Sealed to one in which to perform the steps on a computer.

  By distinguishing the update time of system data and the update time of user data in this way, the update result of the system data is secured as snapshot data, and when the system is terminated, the state at the completion of the update is obtained. It can be restored. In other words, it is possible to guarantee that no user data remains while the update of the system program is held in the data storage unit.

  Further, when the end of the system based on the system data is detected, the computer may be caused to further execute a step of restoring the data recording unit to the state when the update of the system data is completed by the snapshot data. Data management in the data recording unit includes (1) a method for managing state data when updating is completed and differential data including user data, and (2) a system for saving state when update is completed. There is a method for managing data, user data, and all system data for work.

  Further, the data recording unit may be a portable storage medium connected to the computer via a universal serial bus. It may be a USB memory or a USB-HDD.

  In addition, when the system is started based on the system data, the step of determining whether the data recording unit is restored to the state at the completion of the update of the system data, and the state of the data recording unit at the completion of the update of the system data If not restored, the computer may further execute a step of restoring to the state at the time of updating the system data with the snapshot data. For example, if the restoration process using snapshot data is not executed at the time of system termination, but is abnormally terminated, for example, by removing the USB memory from the PC, user data may remain in the data recording unit. . Therefore, by automatically executing the processing described above at the time of starting the system, it is possible to cope with the abnormal end and prevent the user data from being read illegally.

  In addition, when the system based on the system data is started, a step of registering the start of use of the data recording unit in the management server via the network, and when the end of the system based on the system data is detected, the management server is notified via the network. The step of registering the end of use of the data recording unit may be further executed by the computer. In this way, the use status of the data recording unit can be managed by the management server. For example, when the use start is registered again without registering the end of use, since the end is incorrect, a measure such as setting so that the use cannot be started may be performed. .

  The program according to the second aspect of the present invention includes a first virtual machine control program, a virtual machine, a system program that operates on the virtual machine, and a second virtual machine control program that operates on the system program. Including. A step of determining whether the first virtual machine control program is the latest system program; and a step of causing the virtual machine to block acceptance of user input when it is determined that the system program is not the latest And let the computer run. Further, the second virtual machine control program causes the computer to execute the step of causing the update data of the system program to be acquired from the update server via the network and updating the system program. When the first virtual machine control program further detects completion of the update of the system program, a data recording unit in which the system program is recorded and user data can be stored is displayed when the update of the system program is completed. The virtual machine secures snapshot data for restoring to the state in the virtual machine in the data recording unit, and after the snapshot data is secured in the data recording unit, the virtual machine stops receiving and blocking user input And further causing the computer to execute the steps.

  The program is basically stored and distributed in a portable storage medium such as a USB memory. For example, the program is a storage medium such as a flexible disk, a CD-ROM, a magneto-optical disk, a semiconductor memory, a hard disk, or the like. In some cases, the data is stored in a storage device and distributed. Moreover, it may be distributed as a digital signal via a network or the like. The intermediate processing result is temporarily stored in a storage device such as a main memory.

  According to the present invention, the update of the system program can be saved in a portable storage medium such as a USB memory, while ensuring that no user data remains.

  FIG. 1 shows an outline of a system according to an embodiment of the present invention. The PC 300 is connected to a file server 400 and an update server 500 that holds update data of system programs such as an OS and applications via a network 1 such as the Internet. The PC 300 has a USB terminal as an external terminal, and can be connected to a portable storage medium 100 such as a USB memory or a USB-connected portable HDD. The portable storage medium 100 includes a USB target controller 102 for recognizing that a memory is connected to the PC 300, and a storage area 200. The USB target controller 102 is well known and will not be described further. The storage area 200 in the initial state stores a first virtual machine control application 203, a virtual machine 204, and a virtual machine OS image 205 including an application that runs on the OS. The virtual machine OS image 205 includes a second virtual machine control application 206 that operates on the virtual machine in cooperation with the first virtual machine control application 203.

  Next, processing when the portable storage medium 100 is connected to the PC 300 will be described with reference to FIGS. First, the user inserts the portable storage medium 100 into the USB terminal of the PC 300. The PC 300 accepts insertion of the portable storage medium 100 (step S1), and activates the first virtual machine control application 203 on the OS of the PC 300 (step S3). The first virtual machine control application 203 is activated as the first virtual machine control application 303 that is a process on the OS of the PC 300 (step S5). Note that user authentication may be performed before the storage area 200 is accessed. The first virtual machine control application 203 may be activated automatically as shown in FIG. 2 or may be activated according to a user instruction. FIG. 3 schematically shows a state when step S5 is completed. A state in which the portable storage medium 100 is connected to the PC 300 and the first virtual machine control application 303 is activated as a process on the OS of the PC 300 is shown.

  In addition, the first virtual machine control application 303 activates the virtual machine 204 (step S7). The virtual machine 204 is activated as a virtual machine 304 that is a process on the OS of the PC 300 (step S9). Further, the virtual machine 304 loads and activates the virtual machine OS image 205 (step S11). The virtual machine OS image 305 is a virtual machine OS image 205 loaded and activated on the virtual machine 304, and operates as a virtual machine OS 305 '(step S13). The virtual machine OS 305 'activates the second virtual machine control application 206 on the virtual machine OS 305' (step S15). The second virtual machine control application 306 is activated as a process on the virtual machine OS 305 '(step S17).

  At this stage, the first virtual machine control application 303 and the second virtual machine control application 306 generate a communication session 310. A communication session can be generated by using a socket or using an interprocess shared memory. FIG. 4 schematically shows the state after the processing has progressed to this stage. As shown in FIG. 4, the first virtual machine control application 303 and the virtual machine 304 operate as processes on the OS of the PC 300, and the virtual machine OS image 305 is activated on the virtual machine 304. Further, the second virtual machine control application 306 operates as a process on the virtual machine OS 305 ′. The first virtual machine control application 303 and the second virtual machine control application 306 have a communication session 310 so that they can communicate with each other.

  Next, the first virtual machine control application 303 outputs a confirmation request for confirming whether or not the virtual machine OS image 305 is the latest one to the second virtual machine control application 306 via the communication session 310 (step S19). . The second virtual machine control application 306 receives the confirmation request from the first virtual machine control application 303 (step S21), and proceeds to the processing of FIG.

  Shifting to the description of the processing in FIG. 5, the second virtual machine control application 306 requests the update server 500 for the latest state information such as the OS (step S23). When the update server 500 receives a request for the latest status information such as the OS from the PC 300 (step S25), the update server 500 transmits the latest status information such as the OS to the transmission source PC 300 (step S27). The second virtual machine control application 306 receives the latest state information such as the OS from the update server 500 (step S29). The second virtual machine control application 306 acquires current OS state information (system version and update status information) from the virtual machine OS image 305 (step S31). For example, read from the registry or a specific file.

  Then, the second virtual machine control application 306 compares the latest state information such as the OS with the current OS state information (step S33). Then, the comparison result is output to the first virtual machine control application 303 via the communication session 310 (step S35). The first virtual machine control application 303 receives the comparison result between the latest state information such as the OS and the current OS state information from the second virtual machine control application 306 (step S37), and sends an input suppression request to the virtual machine 304. Output (step S41). The virtual machine 304 receives the input suppression request and performs input suppression (step S42). In addition, the first virtual machine control application 303 confirms whether the comparison result received from the second virtual machine control application 306 indicates the latest (step S43). If it is the latest, the process proceeds to the process of FIG. On the other hand, if it is not the latest, the first virtual machine processing shifts to the processing in FIG.

  The input suppression will be described with reference to FIG. Normally, keyboard input from the keyboard 320 connected to the PC 300 is output to the virtual machine 304, which is an OS process of the PC 300, via the keyboard input controller 331 and the driver 332 ((1) to (3)). . The keyboard input data is transferred from the virtual machine 304 to the virtual machine OS image 305 ((4)). In step S42, the first virtual machine control application 303 causes the virtual machine 304 to suppress transfer to the virtual machine OS image 305. Not only the keyboard but also the mouse input may be similarly suppressed.

  By doing so, input from the PC 300 is suppressed while the virtual machine OS images 305 and 205 are being updated, so that no application is executed on the virtual machine 204. In other words, the user cannot create a new document or download the document from the file server 400 via the network 1.

  Processing after the terminal C will be described with reference to FIG. The first virtual machine control application 303 outputs an update request for the virtual machine OS image 305 to the second virtual machine control application 306 via the communication session 310 (step S45). The second virtual machine control application 306 receives an update request for the virtual machine OS image 305 from the first virtual machine control application 303 (step S47), and updates the update module in the virtual machine OS image 305 with the OS and the like. An update request is output (step S49). When the update module in the virtual machine OS image 305 receives an update request for the OS or the like from the second virtual machine control application 306 (step S51), the update module transmits a status update information request for the OS or the like to the update server 500 (step S53). . When the update server 500 receives a status update information request such as an OS from the PC 300 (step S55), the update server 500 transmits status update information such as the OS to the transmission source PC 300 (step S57). At this time, necessary authentication processing may be performed. Further, since what kind of information is extracted and transmitted is well known, description thereof is omitted here. The update module in the virtual machine OS image 305 receives status update information such as the OS from the update server 500, and performs an update process (step S59). When the update server 500 finishes transmitting the state update information, the update server 500 transmits an update end notification to the requesting PC 300 (step S61). On the other hand, the update module in the virtual machine OS image 305 receives the update end notification (step S63) and ends the update. The processing shifts to the processing in FIG.

  The processing after the terminal D will be described with reference to FIG. The update module in the virtual machine OS image 305 outputs an update end notification to the second virtual machine control application 306 (step S65). When the second virtual machine control application 306 receives the update end notification from the update module in the virtual machine OS image 305 (step S67), the second virtual machine control application 306 outputs the update end notification to the first virtual machine control application 303 via the communication session 310. (Step S69). When receiving the update end notification from the second virtual machine control application 306 (step S71), the first virtual machine control application 303 outputs a snapshot generation request to the virtual machine 304 (step S73). The virtual machine 304 receives the snapshot generation request from the first virtual machine control application 303, generates a snapshot image, and stores it in the storage area 200 of the portable storage medium 100 (step S75).

  The snapshot data is data as shown in FIG. 9, for example. As shown in FIG. 9, the snapshot image is an image of an OS, a word processor application, and other applications, and is the virtual machine OS image 205 itself at the time of step S75. If the virtual machine OS image is not the latest and needs to be updated, the same snapshot data as the virtual machine OS image 205 after the update is generated in step S59 is generated. If the virtual machine OS image is the latest and no update is required, a snapshot image is generated without updating.

  FIG. 10 is a diagram conceptually showing the transition of the virtual machine OS image 205 and snapshot data stored in the storage area 200. Prior to step S75, as shown in FIG. 10A, the virtual machine OS image 205 “A” is stored in the storage area 200. As illustrated in FIG. 9, when the snapshot image is generated in step S <b> 75, “A” that is the same snapshot image as “A” that is the virtual machine OS image 205 is generated. "Will be held. Note that A (for saving) is a snapshot image, and A (Current) is a virtual machine OS image 205 that may be changed in the future. The following will be described in the process described below.

  Returning to the description of FIG. 8, the virtual machine 304 updates the snapshot management table (step S77). The snapshot management table manages virtual machine OS images 205 and snapshot images stored in the storage area 200. The virtual machine OS image 205 is updated by data writing by various application programs as described below. Since such an update is an update that should not be saved when the portable storage medium 100 is removed from the PC 300, a snapshot image is separately stored, and the storage area 200 is stored with the snapshot image. Return to the original state. Therefore, as shown in FIG. 11, the snapshot management table 350 is a restore snapshot image (also referred to as snapshot data) 207, which is the currently used virtual machine OS image 205. A record specifying whether the current is (Current) is held. For example, in step S77, as shown in FIG. 11, according to the notation of FIG. 10, a record such as “A (for saving)”-> “A (Current)” is held. “A (Current)” indicates the virtual machine OS image 205, and “A (for storage)” indicates the snapshot image 207. Note that the snapshot management table 350 is also stored in the storage area 200.

  Further, the first virtual machine control application 303 outputs an input suppression stop instruction to the virtual machine 304 (step S79). The virtual machine 304 receives the input suppression stop instruction and stops the input suppression (step S81). And it transfers to the process of FIG. The processing after the terminal A is also the processing in FIG.

  Shifting to the description of the processing in FIG. 12, here, it is assumed that the user selects, for example, a word processor application and inputs an activation instruction to the PC 300. In such a case, the activation instruction is transmitted to the virtual machine OS 305 'via the virtual machine 304, and the word processor application is activated (step S81). Here, consider a case where the user edits a specific document file stored in the file server 400. That is, the user inputs an instruction to download a specific document file from the file server 400. Then, the word processor application requests the file server 400 to download a specific document file in accordance with the instruction (step S83). The file server 400 receives a download request for a specific document file (step S85), and transmits the requested document file to the requesting PC 300 (step S87). The word processor application receives the document file from the file server 400 and displays the content of the document on the display device (step S89).

  Further, it is assumed that the user instructs to temporarily store the received document file in the storage area 200 of the portable storage medium 100 for work. Then, in response to the instruction, the word processor application requests the virtual machine OS 305 'to save the document file (step S91). In response to a request from the word processor application, the virtual machine OS 305 'saves the document file in the storage area 200 of the portable storage medium 100 (step S93). At this stage, as shown in FIG. 10C, the virtual machine OS image 205 (that is, “A (Current)” on the right side) in the storage area 200 of the portable storage medium 100 is changed to “A +”. Changes occur as described in (After change).

  Thereafter, the user edits the document file, and the word processor application executes the document file editing process in accordance with the editing instruction (step S95). When the user instructs saving, the word processor application requests the virtual machine OS 305 'to save the editing result in accordance with the instruction (step S97). The virtual machine OS 305 'saves the edited result in the storage area 200 of the portable storage medium 100 in response to a request from the word processor application (step S99). Since the document file cannot be held in the portable storage medium 100, when editing is completed, the user instructs the word processor application to upload to the file server 400. The word processor application uploads the edited document file to the file server 400 in accordance with an instruction from the user (step S101). The file server 400 receives the edited document file from the PC 300 and stores it in the storage device of the file server 400 (step S103). The processing shifts to the processing in FIG.

  Shifting to the description of the processing in FIG. 13, when the use of the portable storage medium 100 ends, the user first instructs the end of the word processor application. Then, the word processor application is terminated according to the instruction (step S105). Further, the user gives an instruction to end the virtual machine OS 305 ', and the virtual machine OS 305' is ended in response to the instruction (step S107). When the virtual machine 304 detects the end of the virtual machine OS 305 ′ (step S109), the virtual machine 304 deletes the virtual machine OS image 205 in the storage area 200 of the portable storage medium 100, and saves the snapshot image. By leaving only 207, a process for returning the snapshot to the previous one is performed (step S111). Further, the snapshot management table 350 is updated so as to delete the record corresponding to the virtual machine OS image 205 that has been changed so far (step S113). Regarding the snapshot management table 350, not only the table on the memory of the PC 300 but also the table in the storage area 200 of the portable storage medium 100 is updated.

  The state of the system at this stage is schematically shown in FIG. As shown in FIG. 14, in the snapshot management table 350, “A (Current)” that is a record corresponding to the virtual machine OS image 205 is deleted, and “A (Current)” that is a record corresponding to the snapshot image 207 is “A”. (For preservation) "only remains. A snapshot management table 250 having the same contents is held in the storage area 200 of the portable storage medium 100. In the storage area 200, the virtual machine OS image 205 is also deleted in order to delete the document file and other data saved by the user. In this manner, the state returns to “A” (FIG. 10D), which is the same as the state after the update of the virtual machine OS image 205, from the state of FIG.

  Thereafter, the virtual machine 304 is terminated (step S115). Further, the first virtual machine control application 303 detects the end of the virtual machine 304 and is ended (step S117). After such processing, the user can remove the portable storage medium 100 from the PC 300 and carry it.

  By performing the processing as described above, the updated state of the virtual machine OS image 205 can be retained without leaving user data in the storage area 200 of the portable storage medium 100. become able to. Therefore, when the portable storage medium 100 is inserted into the PC 300 again, it can be activated using the snapshot image 207.

  However, if the processing described above is normally completed until the end, the snapshot image 207 remains and the record of the snapshot management table 350 indicates that the snapshot image 207 is retained. There may be a case where the user or another person forcibly removes the portable storage medium 100 from the PC 300 without performing normal termination processing.

  In such a case, the virtual machine OS image 205 including user data remains, and a record corresponding to the virtual machine OS image 205 also remains in the snapshot management table 350. If so, user data may be extracted later, leading to information leakage.

  Therefore, for example, after step S3 in FIG. 2, processing as shown in FIG. 15 is performed. That is, the first virtual machine control application 303 checks the snapshot management table 350 (step S201), and determines whether a plurality of records exist (step S203). Note that it may be determined whether a plurality of virtual machine OS images are stored in the storage area 200.

  If it is determined here that there is only one record, no special processing is required, and the next processing may be performed. On the other hand, as shown in FIG. 16B, in the case of illegal termination, a record “A + (Current)” corresponding to the virtual machine OS image 205 that may contain a change by user data. There may be a plurality of records such as a record “A (for saving)” corresponding to the snapshot image 207 after the OS update. In such a case, two virtual machine OS images may remain in the storage area 200 as shown in FIG. Accordingly, when there are a plurality of records, the first virtual machine control application 303 deletes the latest snapshot image in the storage area 200 (step S205). The latest is a snapshot image including a change by user data, and is the virtual machine OS image 205. Then, the snapshot management table 250 is updated to delete the record corresponding to the deleted snapshot image (step S207). Then, the process proceeds to the next process.

  By executing such a process, only the virtual machine OS image that does not include user data is stored in the storage area 200 of the portable storage medium 100 before the virtual machine OS image is read. Thus, it is possible to prevent unauthorized reading of user data.

  In addition, when a company employee is a user, the company may grasp the usage status of the portable storage medium 100 and use it for preventing information leakage. In such a case, as shown in FIG. 17, the management server 600 is newly provided in the network 1, and the processing described below is performed in the storage area 200 of the portable storage medium 100. A virtual machine control application 203b is provided.

  In such a case, steps S301 to S311 shown in FIG. 18 are executed after step S3 in FIG. 2, and steps S313 to S317 shown in FIG. 18 are executed before step S117 in FIG.

  When the first virtual machine control application 303b is activated on the PC 300 as a process from the first virtual machine control application 203b, the first virtual machine control application 303b is activated and the identification information of the portable storage medium 100 (for example, A use start notification including a production number and the like is generated and transmitted to the management server 600 (step S301). The management server 600 receives the use start notification from the PC 300 and stores it in a storage device such as a main memory (step S303). Then, a random number is generated (step S305), and the activation date and time, the identification information of the portable storage medium 100 and the random number included in the use start notification are stored in, for example, the management table (step S307). Then, the management server 600 transmits a random number to the PC 300 that is the transmission source of the use start notification (step S309).

  The first virtual machine control application 303b of the PC 300 receives the random number from the management server 600 and stores it in the main memory or the storage area 200 of the portable storage medium 100 (step S311).

  On the other hand, before the first virtual machine control application 303b is terminated, when the first virtual machine control application 303b detects the termination of the virtual machine 304, the random number received in step S311 and the identification information and use of the portable storage medium 100 are used. A use end notification including the end date and time is generated and transmitted to the management server 600 (step S313). When the management server 600 receives a usage end notification including a random number, identification information of the portable storage medium 100 and the usage end date and time from the PC 300 (step S315), the management server 600 searches the management table with the identification information of the portable storage medium 100, for example. If it is confirmed that the random number is correct, the use end date and time is registered in the corresponding record of the management table (step S317).

  If the process as described above is performed, it is possible to determine whether the portable storage medium 100 is appropriately used based on the data stored in the management server 600. Specifically, if the pair of start date / time and end date / time of use is not registered, it is actually in use or has not ended normally during use. If is not registered, it is understood that the process has not been completed normally.

  Furthermore, when there is a record in which the use end date / time is not registered, but the use start notification is received again for the same portable storage medium 100, there is a possibility that the user has been stolen in the middle. A lock instruction is transmitted from the management server 600 to the first virtual machine control application 203b so that loading of the virtual machine 204 and the virtual machine OS image 205 is prohibited, and access to the portable storage medium 100 is prohibited. Information leakage may be prevented. Further, the management server 600 and the file server 400 are linked so that when the use end date / time is not registered and the normal use time exceeds the start date / time, the corresponding user area of the file server 400 is locked. May be.

  In the above example, in the snapshot generation, the same data as the virtual machine OS image 205 is generated and the snapshot image 207 is generated. However, in this example, the virtual image is stored in the storage area 200 of the portable storage medium 100. The storage capacity is almost twice that of the machine OS image 205. This makes the portable storage medium 100 expensive. Therefore, when a snapshot is generated for the virtual machine OS image 205 (FIG. 19A) “A”, “A” is retained for read-only storage (FIG. 19B). When a change occurs due to user data generation or the like by a word processor application or the like, only the changed part is stored as “a +” separately from the virtual machine OS image 205 “A” (FIG. 19C). ). At the end, the original virtual machine OS image 205 “A” is restored by deleting the changed part “a +” (FIG. 19D). In this way, since the necessary storage capacity is increased by “a +”, the price of the portable storage medium 100 to be used can be reduced.

  Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, as long as the same result can be obtained, the order of the processing steps described above may be changed or may be executed simultaneously. Further, for example, the function sharing between the first virtual machine control application 303 and the virtual machine 304 may be changed.

  In the above-described PC 300, file server 400, update server 500, and management server 600, as shown in FIG. 20, a memory 2501 (storage unit), a CPU 2503 (processing unit), a hard disk drive (HDD) 2505, A display control unit 2507 connected to the display device 2509, a drive device 2513 for a removable disk 2511, an input device 2515, and a communication control unit 2517 for connecting to a network are connected by a bus 2519. Application programs including the OS and the Web browser are stored in the HDD 2505, and are read from the HDD 2505 to the memory 2501 when executed by the CPU 2503. If necessary, the CPU 2503 controls the display control unit 2507, the communication control unit 2517, and the drive device 2513 to perform necessary operations. Further, data in the middle of processing is stored in the memory 2501 and stored in the HDD 2505 if necessary. Such a computer realizes various functions as described above by organically cooperating hardware such as the CPU 2503 and the memory 2501 described above with the OS and necessary application programs.

(Appendix 1)
Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A program that causes a computer to execute.

(Appendix 2)
The system for causing the computer to further execute a step of restoring the data recording unit to a state at the time when the update of the system data is completed by the snapshot data when detecting the end of the system based on the system data. Program.

(Appendix 3)
The program according to claim 1, wherein the data recording unit is a portable storage medium connected to the computer via a universal serial bus.

(Appendix 4)
Determining whether the data recording unit has been restored to the state when the update of the system data is completed at the time of starting the system based on the system data;
When the data recording unit is not restored to the state at the time of completion of the update of the system data, the step of restoring to the state at the time of update of the system data by the snapshot data;
The program according to claim 2, further causing a computer to execute.

(Appendix 5)
Registering the start of use of the data recording unit in a management server via a network when starting the system based on the system data;
Detecting the end of the system based on the system data, causing the management server to register the end of use of the data recording unit via the network;
The program according to claim 1, further causing a computer to execute.

(Appendix 6)
A first virtual machine control program;
A virtual machine,
A system program running on the virtual machine;
A second virtual machine control program operating on the system program;
A program including
The first virtual machine control program is
Determining whether the system program is up-to-date;
If it is determined that the system program is not up-to-date, causing the virtual machine to block acceptance of user input;
To the computer,
The second virtual machine control program is
Causing the computer to execute the step of acquiring update data of the system program from an update server via a network and executing the update of the system program;
The first virtual machine control program further includes:
When detecting the completion of the update of the system program, a snapshot for restoring the data recording unit in which the system program is recorded and in which user data can be stored to the state when the update of the system program is completed Causing the virtual machine to secure data in the data recording unit;
Stopping the virtual machine from accepting and blocking the user input after the snapshot data is secured in the data recording unit;
A program for causing the computer to further execute.

(Appendix 7)
Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A portable storage medium that stores a program for causing a computer to execute the program in the data storage unit and can be connected to the computer via a universal serial bus.

(Appendix 8)
Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A control method executed by a computer.

It is a system outline figure of the initial state in an embodiment of the invention. It is a figure which shows the 1st part of the processing flow in embodiment of this invention. It is a system outline figure of the 2nd state in an embodiment of the invention. It is a system outline figure of the 3rd state in an embodiment of the invention. It is a figure which shows the 2nd part of the processing flow in embodiment of this invention. It is a figure for demonstrating the outline | summary of the input suppression by a 1st virtual machine control application. It is a figure which shows the 3rd part of the processing flow in embodiment of this invention. It is a figure which shows the 4th part of the processing flow in embodiment of this invention. It is a schematic diagram for demonstrating a snapshot. It is a figure for demonstrating transition of a snapshot. It is a system outline figure of the 4th state in an embodiment of the invention. It is a figure which shows the 5th part of the processing flow in embodiment of this invention. It is a figure which shows the 6th part of the processing flow in embodiment of this invention. It is a system outline figure of the 5th state in an embodiment of the invention. It is a figure which shows the other example of the initial process in embodiment of this invention. (A) And (b) is a figure for showing the problem at the time of improper termination. It is a figure which shows the system schematic diagram in the case of introducing a management server. It is a figure which shows the processing flow in the case of introducing a management server. It is a figure for demonstrating the method for reducing the memory capacity of a snapshot. It is a functional block diagram of a computer.

Explanation of symbols

100 portable storage medium 200 storage area 300 PC
400 File server 500 Update server 600 Management server 102 USB target controller 203, 303 First virtual machine control application 204, 304 Virtual machine 205, 305 Virtual machine OS image 206, 306 Second virtual machine control application 207 Snapshot image 250, 350 Snapshot management table 310 Communication session 320 Keyboard 331 Keyboard input controller 332 Driver

Claims (8)

Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A program that causes a computer to execute. The system for causing the computer to further execute a step of restoring the data recording unit to a state at the time when the update of the system data is completed by the snapshot data when detecting the end of the system based on the system data. Program. The program according to claim 1, wherein the data recording unit is a portable storage medium connected to the computer via a universal serial bus. Determining whether the data recording unit has been restored to the state when the update of the system data is completed at the time of starting the system based on the system data;
When the data recording unit is not restored to the state at the time of completion of the update of the system data, the step of restoring to the state at the time of update of the system data by the snapshot data;
The program according to claim 2, further causing a computer to execute. Registering the start of use of the data recording unit in a management server via a network when starting the system based on the system data;
Detecting the end of the system based on the system data, causing the management server to register the end of use of the data recording unit via the network;
The program according to claim 1, further causing a computer to execute. A first virtual machine control program;
A virtual machine,
A system program running on the virtual machine;
A second virtual machine control program operating on the system program;
A program including
The first virtual machine control program is
Determining whether the system program is up-to-date;
If it is determined that the system program is not up-to-date, causing the virtual machine to block acceptance of user input;
To the computer,
The second virtual machine control program is
Causing the computer to execute the step of acquiring update data of the system program from an update server via a network and executing the update of the system program;
The first virtual machine control program further includes:
When detecting the completion of the update of the system program, a snapshot for restoring the data recording unit in which the system program is recorded and in which user data can be stored to the state when the update of the system program is completed Causing the virtual machine to secure data in the data recording unit;
Stopping the virtual machine from accepting and blocking the user input after the snapshot data is secured in the data recording unit;
A program for causing the computer to further execute. Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A portable storage medium that stores a program for causing a computer to execute the program in the data storage unit and can be connected to the computer via a universal serial bus. Determining whether system data, including application data, is current;
If it is determined that the system data is not up-to-date, blocking acceptance of user input;
Obtaining update data of the system data from an update server via a network, and performing the update of the system data;
When detecting the completion of the update of the system data, a snapshot for restoring the data recording unit in which the system data is recorded and the user data can be stored to the state at the completion of the update of the system data. Securing data in the data recording unit;
After the snapshot data is secured in the data recording unit, stopping the acceptance and blocking of the user input;
A control method executed by a computer.

Images