JP2009260821A - Communication device and communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication technique capable of deleting connection information that does not have to be stored, when a plurality of master-side communication devices are present with respect to a slave-side communication device for exchanging connection information through sub communication between two slave and master communication devices. <P>SOLUTION: A control unit 10 of a slave device D1 stores connection information exchanged with a master device P through sub communication in a RAM 11 and stores the connection information in a nonvolatile memory 13 in response to a connection information storage flag. Then, the control unit 10 of the slave device D1 deletes the connection information from the RAM 11 in accordance with a communication status in at least one of sub communication and main communication and a condition indicated in connection information deletion condition information stored in the nonvolatile memory 13. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication apparatus and a communication method for performing wireless communication.

  In recent years, wireless communication has been rapidly spread, and various communication devices that perform wireless communication have been developed (see, for example, Patent Documents 1 to 3). The wireless communications are connected by establishing a wireless link between the wireless communication devices, and can communicate with each other. That is, unlike wired communication, wireless communication is possible without physically connecting communication devices. For this reason, a third party can intercept data. In order to prevent such eavesdropping, some communication devices perform encrypted communication in which data is encrypted and communicated. Before starting encrypted communication for the first time between communication devices, connection information including mutual authentication information and an encryption key used for encrypted communication is exchanged and shared. In general, these pieces of connection information are exchanged using secure means and stored in a nonvolatile memory or the like. The stored connection information is used as it is in the next connection. This is conventionally interpreted as the complexity of wireless communication, and means for easily exchanging this connection information has been devised.

  The exchange of connection information is broadly classified into an In Band method for exchanging using a target wireless communication itself and an Out Of Band method for exchanging using another route. In recent years, as an application to the latter out-of-band method, an exchange means using a method of performing wireless communication at a lower speed and closer distance than the main communication as a sub-communication is considered promising, and its practical application has progressed. As a method of performing this sub-communication, for example, there is NFC (Near Field Communication). In such a method, since connection information is exchanged in a state of almost contact, physical security is ensured, and connection information can be easily exchanged by an intuitive operation. For this reason, it can be said that it is excellent in usability.

  On the other hand, as a communication topology for wireless communication, there is one main device (main communication device) responsible for overall control and one or more subordinate devices (subordinate communication devices) connected thereto. . For example, in wireless communication based on the WUSB standard realized by UWB (Ultra Wide Band) or the like, a WUSB host as a main device and a WUSB device as a subordinate device exist. The main device and the subordinate device hold both connection information as CCs (connection contexts) by performing association as the above-described information exchange and sharing before connecting to each other for the first time after starting wireless communication. Basically, the main device needs connection information as many as the number of subordinate devices to be connected, and the subordinate device only needs to hold one piece of connection information with the main device to be connected.

JP 2006-287860 A JP 2006-197071 A JP 2006-195627 A

  However, when an application that is shared by the user is installed in the subordinate device, it is necessary to share it among users who use a plurality of main devices. For example, it is assumed that an unspecified number of users use a subordinate device on which a shared application service provided for a fee is installed from different main devices. In this case, it is considered that the user performs the work of exchanging connection information by a predetermined means, performing wireless communication using the connection information, and disconnecting after the use of the service is completed. As described above, when the main device to be connected is not unique to some extent and most of the devices are temporary, it is considered that the subordinate device does not need to keep the previous connection information, that is, does not need to store it.

  For example, the tendency becomes remarkable in the following cases. The portable main device equipped with NFC or the like described above exchanges connection information by sub-communication in order to easily use a stationary subordinate device from a short distance, and is fast for application services. This is a case where the main communication is temporarily used. The purpose of storing the connection information is to facilitate the second and subsequent connections when the main device to be connected is unique. For this reason, when most of the devices are temporarily connected from the main device, storing them conversely becomes a problem.

  The first demerit is that the connection information is saved, so that there is a possibility that the main device that has been connected in the vicinity and that has been connected before is automatically connected unintentionally. This means that one main device may continue to occupy the connection. In order to avoid such an unintended connection, various devices have been devised, such as a means for storing several pieces of connection information with the main device listed as the prior art and controlling the connection priority order. However, there is a possibility that the cost increases due to an increase in the storage area in the non-volatile memory, and this is a disadvantage when the subordinate device is a product with strict cost requirements. In addition, such an approach requires complicated implementation and operation for management. When assuming that the connection information using NFC is intuitively exchanged, the subordinate device can be easily changed. There is a risk that the original purpose of “to connect and use” is completely lost.

  As a second disadvantage, storing connection information with a main device that does not need to be stored is problematic from the viewpoint of security. In wireless communication, the connection information mostly includes information such as the ID information of the main device and the encryption key used for authentication. Therefore, if the main device is hardly unique, it should not be stored. , The user may not want it.

  Because of the above disadvantages, if the subordinate device that is not supposed to be connected from a unique main device in the first place allows users using NFC to easily use main communication, It can be said that it may not be desirable to keep the connection information.

  The present invention has been made in view of the above, and there are a plurality of communication devices on the master side with respect to a communication device on the slave side that exchanges connection information between two communication devices having a master-slave relationship by sub-communication. If possible, an object of the present invention is to provide a communication device and a communication method capable of deleting connection information that does not need to be held.

  In order to solve the above-described problems and achieve the object, the invention according to claim 1 encrypts information including identification information and communication data for identifying each other between two communication devices having a master-slave relationship. A subordinate communication device including main communication means for performing the first wireless communication, and a main communication device connectable to the subordinate communication device among the plurality of main communication devices. Connection information including detection means for detecting, the identification information used when performing wireless communication with the main communication apparatus detected by the detection means, and an encryption key used for encrypting the information, Sub-communication means for exchanging by performing second wireless communication with the communication device, temporary storage means for temporarily storing the connection information exchanged by the sub-communication means, the sub-communication means and the main communication means At least one of them Depending on the state, and further comprising a deleting means for deleting the connection information stored in the temporary storage means.

  Further, the invention according to claim 2 is the invention according to claim 1, wherein the deletion means, when the communication link in the sub communication means is invalid as the communication state in the sub communication means, It is characterized by deleting.

  Further, the invention according to claim 3 is the invention according to claim 1 or 2, wherein the deletion means has a first restriction when the communication link in the sub-communication means is invalid and the communication link is invalid. The connection information is deleted when it continues for more than a time.

  The invention according to claim 4 is the invention according to claim 3, further comprising first setting means for setting the first time limit in advance, wherein the deletion means has an invalid communication link in the sub-communication means. In some cases and when the state where the communication link is invalid continues for the first time limit set by the first setting means, the connection information is deleted.

  Further, the invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the deletion means has an effective communication link in the sub-communication means as a communication state in the sub-communication means. And the connection information is deleted when the communication link is valid for a second time limit or more.

  Further, the invention according to claim 6 is the invention according to claim 5, further comprising second setting means for presetting the second time limit, wherein the deletion means has an effective communication link in the sub-communication means. In some cases and when the communication link is valid for more than the second time limit set by the second setting means, the connection information is deleted.

  According to a seventh aspect of the present invention, in the invention according to any one of the first to sixth aspects, the deletion unit is configured to determine a communication state in the main communication unit according to communication traffic in the main communication unit. The connection information is deleted.

  The invention according to claim 8 is the invention according to claim 7, further comprising third setting means for presetting whether or not to delete the connection information in accordance with the communication traffic, When the third setting unit is configured to delete the connection information according to the communication traffic, the connection information is deleted according to the communication traffic.

  According to a ninth aspect of the present invention, in the invention according to any one of the first to eighth aspects, the deletion unit is configured to determine a communication state in the main communication unit according to an error rate in the main communication unit. The connection information is deleted.

  The invention according to claim 10 further comprises fourth setting means for presetting whether or not to delete the connection information in accordance with the error rate in the invention according to claim 9, wherein the deleting means comprises: When deleting the connection information according to the error rate is set by the third setting means, the connection information is deleted according to the error rate.

  Further, the invention according to claim 11 is the invention according to any one of claims 1 to 10, wherein the deletion unit is configured to determine a communication state in the main communication unit according to a communication speed in the main communication unit. The connection information is deleted.

  The invention according to claim 12 is the invention according to claim 11, further comprising fifth setting means for presetting whether or not to delete the connection information in accordance with the communication speed, wherein the deleting means includes: When deleting the connection information according to the communication speed is set by the fifth setting means, the connection information is deleted according to the communication speed.

  Further, the invention according to claim 13 is the invention according to any one of claims 1 to 12, wherein the deletion means is a communication state in the main communication means, and the line in the main communication means is disconnected. In addition, the connection information is deleted.

  The invention according to claim 14 is the invention according to claim 13, further comprising sixth setting means for presetting whether or not to delete the connection information when the line is disconnected, wherein the deleting means Deletes the connection information when the line in the main communication means is disconnected, when the sixth setting means sets the deletion of the connection information when the line is disconnected It is characterized by.

  In addition, the invention according to claim 15 is the invention according to any one of claims 7 to 14, wherein the deletion unit is configured such that a predetermined state continues as a communication state of the main communication unit for a predetermined time or more. The connection information is deleted.

  The invention according to a sixteenth aspect is the invention according to the fifteenth aspect, further comprising seventh setting means for presetting the predetermined time, wherein the deleting means is configured such that the predetermined state is determined by the seventh setting means. The connection information is deleted when the set time is continued for the predetermined time or longer.

  The invention according to claim 17 is the invention according to any one of claims 1 to 16, further comprising eighth setting means for presetting the connection allowable effective period, wherein the deletion means The connection information is deleted when the connected state continues for the connection allowable effective period set by the eighth setting means.

  The invention according to claim 18 is the invention according to any one of claims 1 to 17, wherein storage means capable of storing the connection information and whether the connection information is stored in the storage means. Ninth setting means for presetting, and storage control means for storing the connection information in the storage means when the storage means stores the connection information in the ninth setting means. It is characterized by that.

  The invention according to claim 19 is the invention according to any one of claims 1 to 18, wherein the main communication means performs the first wireless communication in accordance with a WUSB (Wireless Universal Serial Bus) standard. Features.

  The invention according to claim 20 is the invention according to any one of claims 1 to 19, wherein the sub-communication means performs second wireless communication by NFC (Near Field Communication). .

  According to a twenty-first aspect of the present invention, there is provided main communication means for performing first wireless communication by encrypting information including identification information and communication data for identifying each other between two communication devices having a master-slave relationship. The slave communication device includes a detection unit, a sub-communication unit, a storage control unit, and a deletion unit, and the detection unit includes a plurality of detection units. A detection step of detecting a main communication device connectable to the slave communication device among the main communication devices that may exist, and the main communication detected by the sub-communication means in the detection step Sub-communication step for exchanging connection information including the identification information used when performing wireless communication with a device and an encryption key used for encrypting the information by performing second wireless communication with the main communication device And the storage control means The storage control step for temporarily storing the connection information exchanged in the sub-communication step in a temporary storage unit, and the deletion unit according to the communication state in at least one of the sub-communication unit and the main communication unit, And a deletion step of deleting the connection information stored in the temporary storage means.

  According to the present invention, there is no need to hold a plurality of main communication devices for a subordinate communication device that exchanges connection information between two communication devices having a master-slave relationship by sub-communication. Connection information can be deleted.

  Exemplary embodiments of a communication apparatus and a communication method according to the present invention will be explained below in detail with reference to the accompanying drawings.

(1) Configuration <Configuration of wireless communication system>
FIG. 1 is a diagram illustrating a configuration of a wireless communication system according to the present embodiment. The wireless communication system according to the present embodiment includes a plurality of wireless communication apparatuses that are the main devices P1 to P3 and a wireless communication apparatus that is the subordinate device D1. The main devices P1 to P3 are personal computers. In particular, the main devices P2 to P3 are portable personal computers (portable information devices). Here, the subordinate device D1 is a multifunction device capable of realizing a printer function for outputting an image, a scanner function for reading an image, and a storage function for storing an image. The subordinate device D1 performs wireless communication with one of the main devices P1 to P3 by encrypting information including identification information for identifying each other and communication data in accordance with, for example, the WUSB standard described above. The communication data is, for example, data instructing image output from one of the main devices P1 to P3 to the subordinate device D1. Further, the subordinate device D1 and the main devices P1 to P3 have a function of performing communication by NFC as described above, and exchange connection information by the communication by NFC. The connection information encrypts information including the main ID for identifying the main devices P1 to P3 and the subordinate ID for identifying the subordinate device D1 as identification information for identifying each other during wireless communication, and information including these IDs and communication data. And an encryption key used for encryption when wireless communication is performed. Here, communication in accordance with the WUSB standard is called main communication, and NFC communication is called sub-communication. Hereinafter, when it is not necessary to distinguish the main devices P1 to P3, they are simply referred to as the main device P.

<Configuration of subordinate device>
FIG. 2 is a block diagram showing the configuration of the subordinate device D1. The slave device D1 includes a control unit 10, a RAM 11, a ROM 12, a nonvolatile memory 13, and a wireless communication device 14. The control unit 10 is constituted by a CPU, and executes various programs stored in the ROM 12, thereby controlling the entire slave device D1 and realizing various functions.

  The RAM 11 is used as a work area when the control unit 10 executes various programs. The ROM 12 stores various programs executed by the control unit 10 and various data. The nonvolatile memory 13 stores connection history information, a connection information storage flag, and connection information deletion condition information, which will be described later. The nonvolatile memory 13 stores connection information shared with the main device P according to the connection information storage flag. Further, the nonvolatile memory 13 stores an image by realizing the storage function described above. The wireless communication device 14 performs communication according to the WUSB standard and NFC communication with an external wireless communication apparatus.

  In addition, the subordinate device D1 includes an engine unit for realizing the printer function and an engine unit for realizing the scanner function, an ASIC for performing image processing when realizing the printer function and the scanner function, and an operation panel ( None of them are shown. The operation panel is formed by integrally forming an operation device for a user to input instructions and a display device for displaying information.

  Next, various functions realized by the control unit 10 will be described. As shown in FIG. 2, the various functions realized here include an OS unit 27, an application unit 20, a security control unit 21, a network control unit 22, an operation port control unit 23, and a file control unit 24. A memory control unit 25, and a system control unit 26. The OS unit 27 includes security information 30, a network protocol 28, and a wireless communication device driver 29, and functions as an operating system. The network protocol 28 is a protocol stack for performing encrypted communication as wireless communication. The wireless communication device driver 29 is a device driver that controls the wireless communication device 14 that performs wireless communication with the main device P that is a connection partner. The application unit 20 includes an application for performing encrypted communication, and includes an association application for exchanging connection information with the main device P of the connection partner. The application unit 20 includes applications for realizing a printer function, a scanner function, and a storage function, and these applications are shared by the main devices P1 to P3. In addition, the application unit 20, the network control unit 22, the network protocol 28, the wireless communication device driver 29, and the security control unit 21 realize a function of performing wireless communication using the UWB technology. The security control unit 21 stores security information including connection information in the nonvolatile memory 13 in accordance with the connection information storage flag. The operation port control unit 23 controls instruction input from the user via the operation panel and display of information on the operation panel. The file control unit 24 controls reading and writing of files. The memory control unit 25 controls reading and writing to a memory such as the RAM 11, the ROM 12, and the nonvolatile memory 13. The system control unit 26 controls the units 20 to 30.

  Next, the data structure of the connection information will be described with reference to FIG. As shown in the figure, as described above, the connection information includes a main ID for identifying the main device P and identification ID for identifying the subordinate device as identification information for identifying each other when performing wireless communication, An encryption key used for encryption of information including identification information and communication data is included. In the present embodiment, the subordinate device D1 temporarily stores in the RAM 11 such connection information exchanged with the connection partner main device that is performing wireless communication. Further, the subordinate device D1 stores the connection information in the nonvolatile memory 13 in accordance with a user setting described later.

  Next, the data structure of the connection history information stored in the nonvolatile memory 13 will be described with reference to FIG. The connection history information indicates a history of connection with each main device P and is associated with the connection information described above. The association is performed using, for example, an assignment number. For example, in the correspondence relationship with the connection information shown in FIG. 3, connection history information for the main device P1 is shown. As shown in the figure, the connection history information includes, as each history information, an exchange date and time, a last connection date and time, a communication amount, an error rate, a communication speed, a distance from the main device P, and an application history. Including. The exchange date and time indicates the date and time when connection information is exchanged with the main device P for the first time. The last connection date and time indicates the date and time when the main device P was last connected. The communication amount indicates the amount of data transmitted / received by performing wireless communication with the main device P. The error rate indicates a rate of an error that occurs when performing wireless communication with the main device P. The communication speed indicates a communication speed when wireless communication is performed with the main device P. These communication amount, error rate, and communication speed are used to determine whether or not a communication obstruction factor has occurred. The application history indicates which of the applications for realizing the printer function, the scanner function, and the storage function described above is used in the subordinate device D1 by performing wireless communication with the main device P.

  The subordinate device D1 stores the exchange date and time of the connection history information when the connection information is exchanged with the main device P for the first time, and then stores that time as the last connection date and time each time it connects to the main device. To do. The subordinate device D1 appropriately detects the communication state in the main communication, calculates and stores the communication amount, error rate, and communication speed, and stores the type of application used. The type of application used can be determined, for example, based on communication data included in information transmitted from the main device P. If the communication data is an instruction to output an image, the subordinate device D1 determines that the type of application is a printer function. When the communication data is an instruction to read an image, the slave device D1 determines that the type of application is a scanner function. When the communication data is an instruction to save an image, the subordinate device D1 determines that the type of application is a storage function. The communication device D1 may accumulate and store the amount of communication every time it connects to the same main device P, or data transmitted and received when it is last connected to the main device P. May be stored. The distance from the main device P is set in advance according to the actual distance.

  Next, the connection information storage flag and the connection information deletion condition information will be described. The connection information storage flag indicates whether or not the connection information is stored in the nonvolatile memory 13, and one of the connection information storage flags is set by a user instruction input via the operation panel. The connection information deletion condition information indicates a condition for deleting connection information according to the communication state of at least one of the sub-communication and the main communication. The condition is set by a user instruction input via the operation panel. Is done.

  Here, setting via the operation panel will be described. FIG. 5 is a diagram exemplifying a setting screen for a user to perform settings relating to storage of connection information. In the setting screen shown in the figure, the user can set whether or not to save the connection information in the nonvolatile memory 13 and a condition for deleting the connection information by inputting an instruction via the operation panel. it can. The connection information flag is set according to whether or not the connection information is stored in the nonvolatile memory 13. By setting a condition for deleting connection information, the condition is set in the above-described connection information deletion condition information. As a condition for deleting the connection information according to the communication state in the sub communication, for example, it can be set whether or not to delete the connection information when the communication link is invalid in the sub communication. Even when the communication link is valid in the sub-communication, the connection information can be deleted by setting the “time until deletion”. Conditions for deleting connection information according to the communication status in the main communication include whether to delete the connection information when the line is disconnected in the main communication and setting the "time from disconnection to deletion" it can. In addition, as a condition for deleting the connection information according to the communication state in the main communication, it is possible to set whether or not to delete the connection information when communication is abnormal. In addition, as a condition for deleting connection information, “communication idle time until deletion” is set as an effective period (connection allowable effective period) for allowing connection even when the line in the main communication is not disconnected. can do. Since the setting on the setting screen relates to the behavior of the connection information, only the administrator may change the setting by requesting login or the like on the setting screen.

  In the configuration as described above, when the control unit 10 of the subordinate device D1 starts wireless communication with the main device P for the first time, it performs mutual authentication with the main device P, and then creates connection information according to a request from the main device P. This is transmitted to the connected main device P via the wireless communication device 14. On the other hand, the main device P of the connection partner stores the connection information in the storage unit of the own device. In this way, the control unit 10 of the subordinate device D1 shares connection information with the main devices P1 to P3 by exchanging connection information, performs processing such as authentication / key exchange using the connection information, and performs wireless communication. Start. As a result, the subordinate device D1 and the main device P are connected, and the radio link between the subordinate device D1 and the main device P is established. Since processing such as authentication / key exchange using the connection information is well known, the description thereof is omitted. In addition, the control unit 10 of the subordinate device D1 refers to the connection information storage flag stored in the nonvolatile memory 13 and creates it when the connection information storage flag indicates that the connection information is stored in the nonvolatile memory 13 The connection information is stored in the nonvolatile memory 13 and the RAM 11, and when the connection information storage flag indicates that the connection information is not stored in the nonvolatile memory 13, the created connection information is stored in the RAM 11. Furthermore, the control unit 10 of the subordinate device D1 stores the date and time at this time in the connection history information as the exchange date and time. Thereafter, the control unit 10 of the subordinate device D1 appropriately detects the communication state in at least one of the sub-communication and the main communication, and according to the condition indicated in the connection information deletion condition information stored in the nonvolatile memory 13, The connection information is deleted from the RAM 11. The control unit 10 of the subordinate device D1 updates the connection history information every time wireless communication is performed with the main device P. When starting the subsequent wireless communication, the control unit 10 of the subordinate device D1 scans for detecting a beacon periodically transmitted from the main device P in order to detect the connectable main device P. Process. When detecting the beacon as a result of the scanning process, the control unit 10 of the subordinate device D1 exchanges connection information with the main device P using the main device P that has transmitted the beacon as a connection partner, and thereafter performs the same process as described above. Do.

<Configuration of main device>
The main device P includes a CPU, a storage unit such as a RAM and a ROM, a communication unit that performs wireless communication, and a bus (none of which is shown) for connecting them, and hardware using a normal computer It has a configuration. Then, the main device P can perform wireless communication according to the WUSB standard and wireless communication by NFC via the communication unit.

(2) Operation Next, a procedure of processing related to storage and deletion of connection information performed when the slave device D1 according to the present embodiment performs wireless communication will be described with reference to FIG. When the subordinate device D1 starts wireless communication, the subordinate device D1 deletes the connection information stored in the RAM 11 (step S1), and performs a scanning process to detect a connectable main device P (step S2). Then, the control unit 10 of the subordinate device D1 performs mutual authentication with the main device P detected as a connection partner as a result of the scanning process, and creates connection information. Then, the subordinate device D1 exchanges connection information with the main device P, performs processing such as authentication / key exchange using the connection information, and starts wireless communication (step S3). Further, when the subordinate device D1 refers to the connection information storage flag stored in the nonvolatile memory 13 and the connection information storage flag indicates that the connection information is stored in the nonvolatile memory 13 (step S4: YES). The created connection information is stored in the nonvolatile memory 13 and the RAM 11 (step S5), and the process proceeds to step S7. On the other hand, when the connection information storage flag indicates that the connection information is not stored in the nonvolatile memory 13 (step S4: NO), the subordinate device D1 stores the created connection information in the RAM 11 (step S6), and step S7. Proceed to Further, the subordinate device D1 stores the date and time at this time in the connection history information as the exchange date and time. Further, the subordinate device D1 appropriately detects the communication state in the main communication with the main device P, and stores the last connection date / time, the communication amount, the error rate, the communication speed, and the application history in the connection history information. .

  In step S <b> 7, the subordinate device D <b> 1 refers to the connection information deletion condition information stored in the nonvolatile memory 13, and determines whether or not a state that matches the condition for deleting the connection information has been reached. When the subordinate device D1 determines that the connection information is to be deleted, the subordinate device D1 determines that the connection information is to be deleted, and the subordinate device D1 determines that the connection information is not in a state to be deleted. Therefore, it is determined not to delete the connection information.

  Here, a processing procedure for determining whether or not to delete the connection information according to the communication state in the sub-communication will be described with reference to FIG. The subordinate device D1 determines in the connection information deletion condition information whether deletion of the connection information is set when the communication link is invalid in the secondary communication (step S20), and the determination result is negative. If YES, the process proceeds to step S21, and it is determined that it is not necessary to delete the connection information. On the other hand, when the determination result of step S20 is affirmative, the subordinate device D1 detects the communication state in the sub-communication and determines whether or not the communication link has become invalid (step S22). If the determination result is negative, the slave device D1 performs the process of step S22 again. If the determination result of step S22 is affirmative, the subordinate device D1 determines whether or not the time until the communication link becomes valid again exceeds the first time limit (step S23). That is, the subordinate device D1 determines whether or not the state where the communication link is invalid continues for the first time limit or more. It is assumed that the value of the first time limit is predetermined and stored in the nonvolatile memory 13, for example. If the former time exceeds the first time limit, the subordinate device D1 determines to delete the connection information (step S24), and if the former time does not exceed the first time limit, the process returns to step S22.

  Next, a procedure of processing for determining whether or not to delete connection information according to the communication state in main communication will be described with reference to FIG. The subordinate device D1 determines whether or not the connection information deletion condition information is set to delete the connection information when the line is disconnected in the main communication (step S40), and the determination result is negative. If there is, the process proceeds to step S45. On the other hand, when the determination result of step S40 is affirmative, the subordinate device D1 detects the communication state in the main communication and determines whether or not the line is disconnected (step S41). If the determination result is affirmative, the subordinate device D1 determines whether or not the time from when the line is disconnected until it is reconnected exceeds the second time limit (step S42). That is, the subordinate device D1 determines whether or not the state where the line is disconnected continues for the second time limit or more (step S42). Note that the value of the second time limit is determined in advance and stored in, for example, the nonvolatile memory 13. If the former time exceeds the latter second time limit, the subordinate device D1 determines to delete the connection information (step S43). If the former time does not exceed the latter second time limit, the process goes to step S44. move on. Also when the determination result of step S41 is negative, the process proceeds to step S44.

  In step S44, the subordinate device D1 determines whether or not the connection allowable effective period set as the communication idle time until deletion in the connection information deletion condition information has passed. If the determination result is affirmative, the process proceeds to step S43, and if the determination result is negative, the process proceeds to step S45. In step S45, the subordinate device D1 determines whether or not the connection information deletion condition information is set to delete the connection information when communication is abnormal, that is, when a communication obstruction factor occurs. If the determination result is negative, the subordinate device D1 determines not to delete the connection information (step S46).

  On the other hand, when the determination result of step S45 is affirmative, the subordinate device D1 determines whether or not a communication inhibition factor has occurred. Specifically, first, the subordinate device D1 detects communication traffic in the main communication and determines whether or not the communication is interrupted (step S47). If the determination result is affirmative, the process proceeds to step S48. . If the determination result in step S47 is negative, the subordinate device D1 determines whether or not the error rate is equal to or higher than the first threshold with reference to the connection history information (step S49). Note that the first threshold value is determined in advance and stored in, for example, the nonvolatile memory 13. If the determination result is affirmative, the process proceeds to step S48, and if the determination result is negative, the process proceeds to step S50. In step S50, the subordinate device D1 refers to the connection history information and determines whether or not the communication speed is equal to or higher than the second threshold value. Note that the second threshold value is determined in advance and stored in, for example, the nonvolatile memory 13. If the determination result is affirmative, the process proceeds to step S48, and if the determination result is negative, the process proceeds to step S46.

  In step S48, the subordinate device D1 determines whether or not a predetermined state as a communication state in the main communication, that is, a state in which the occurrence of a communication hindrance factor has continued for a certain time or longer (step S48). ). Note that the value of the predetermined time is determined in advance and stored in, for example, the nonvolatile memory 13. If the determination result is positive, the process proceeds to step S43. If the determination result is negative, the process proceeds to step S46.

  Returning to the description of FIG. If the subordinate device D1 determines that the connection information is to be deleted as a result of the processing of FIGS. 7 and 8 (step S7: YES), the subordinate device D1 returns to step S1 and deletes the connection information from the RAM 11. Then, the subordinate device D1 performs the processing after step S2. On the other hand, if it is determined not to delete the connection information (step S7: NO), the process proceeds to step S8. In step S8, the subordinate device D1 detects the connectable main device P in the same manner as in steps S2 to S3 when the wireless communication with the main device P is continued and the connection is updated. Then, mutual authentication is performed with the main device P to exchange connection information, processing such as authentication / key exchange using the connection information is performed, wireless communication is started, and the process returns to step S7. If the connection information to be exchanged with the main device P is already stored in the nonvolatile memory 13, the subordinate device D1 may use the stored connection information without newly creating the connection information. it can.

  With the above configuration, when there are multiple main devices for subordinate devices that perform wireless communication by exchanging connection information with the main device through sub-communication, after the exchanged connection information is temporarily stored It is possible to delete this. As a result, it is possible to avoid that the subordinate device is not automatically connected to the main device that has been connected before and exists in the vicinity. Further, it is possible to avoid a decrease in security. Then, it is possible to communicate by connecting the main device to the subordinate device intuitively and easily. This leads to suppression of cost increase and simplification of mounting and operability.

  Further, since the connection information can be stored in the nonvolatile memory 13 according to the user setting, the stored connection information can be used at the next connection. For this reason, it is possible to maintain the convenience of connection while maintaining easy operability by adding a simple implementation of whether or not to save connection information. For this reason, for example, in case the administrator of the subordinate device easily reconnects the subordinate device to the main device for maintenance, the connection information for one main device is stored in the subordinate device. Flexible operation is possible.

  Further, since the user can set conditions for deleting the connection information, the connection information can be deleted according to the usage of the subordinate device. For this reason, it is possible for an administrator or the like to tune the conditions according to the situation or application, and it is possible to operate more flexibly.

  Further, the condition for deleting the connection information can be set, for example, triggered by the occurrence of a state in which the communication link in the sub-communication is invalid. Further, if the user unintentionally disables the communication link in the sub-communication, the communication in the main communication may not be performed, and conversely, the usability may be reduced. For example, in the case where sub-communication is performed by short-range wireless communication such as NFC as described above, it may be assumed that the communication link in sub-communication becomes invalid due to the fall of the main device during communication by the application in main communication. . In order to avoid this, the connection information is deleted when the communication link is disabled in the sub-communication when the state continues for the first time limit or longer. In this way, by giving a certain margin to the time until the connection information is deleted, usability is improved, and the time can be adjusted, which is more effective in application operation.

  In addition, even when the communication link in the secondary communication is enabled unintentionally, it is possible to set the time until the connection information is deleted, and the connection can be established by deleting the connection information according to this setting. It becomes possible to forcibly disconnect. Such a configuration is effective, for example, when the main device is misplaced or when a charge is made for connection with the main device.

  In addition, as a condition for deleting the connection information, for example, as a communication state in the main communication, for example, a state where communication is interrupted and there is no communication traffic, or a communication obstruction factor such as a radio wave interference has occurred, the error rate has become extremely high It can be set as triggered by the occurrence of a state, a state in which the communication speed has decreased due to some communication obstruction factor, or a state in which the line is disconnected in the main communication. Further, flexible mounting can be realized by deleting the connection information when at least one of these states continues for a certain period of time. Further, according to such a configuration, it is possible to manage and operate the connection information more effectively even when the communication link in the sub communication is valid.

[Modification]
Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined. Further, various modifications as exemplified below are possible.

<Modification 1>
In the wireless communication system of the above-described embodiment, the slave device D1 is a multi-function device. However, the wireless communication device is not limited to this, and is a wireless communication device such as a printer device, a scanner device, a fax device, a personal computer, or a portable information terminal. There may be. Further, although the number of subordinate devices is one, it may be plural. Similarly, the number of main devices P is three, but is not limited thereto.

<Modification 2>
In the embodiment described above, various programs executed by the subordinate device D1 may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Further, the program is recorded in a computer-readable recording medium such as a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk), etc. in a file in an installable or executable format. May be configured to be provided.

<Modification 3>
In the embodiment described above, the slave device D1 is configured to include the non-volatile memory 13. However, the slave device D1 may be configured not to include this, and in this case, the connection history information and the connection information are stored only in the RAM 11, for example. It may be stored. Further, the connection history information and the connection information may be stored in separate storage means.

  The RAM 11 is used as temporary storage means for temporarily storing connection information. However, the present invention is not limited to this. For example, a temporary storage area for temporarily storing connection information is provided in the nonvolatile memory 13, and this temporary memory is temporarily stored. The storage area may be used as temporary storage means.

<Modification 4>
In the embodiment described above, the conditions for deleting the connection information are not limited to those described above. Further, the processing procedure for deleting the connection information is not limited to that shown in FIGS.

  Further, the sub-communication is performed by NFC, but the present invention is not limited to this, and the sub-communication may be performed by another communication method. Furthermore, the main communication is performed according to the WUSB standard, but the main communication may be performed according to another communication standard as long as it is a communication standard for exchanging connection information between two communication devices having a master-slave relationship. .

It is a figure which illustrates the structure of the radio | wireless communications system concerning one Embodiment. It is a block diagram which shows the structure of the subordinate device D1 concerning the embodiment. It is a figure which illustrates the data structure of the connection information concerning the embodiment. It is a figure which illustrates the data structure of the connection history information memorize | stored in the non-volatile memory 13 concerning the embodiment. It is a figure which illustrates the setting screen for a user to perform the setting regarding the preservation | save of the connection information concerning the embodiment. It is a flowchart which shows the procedure of the process regarding the preservation | save and deletion of the connection information performed when the subordinate device D1 concerning the embodiment performs wireless communication. It is a flowchart which shows the procedure of the process which judges whether connection information is deleted according to the communication state in the sub communication concerning the embodiment. It is a flowchart which shows the procedure of the process which judges whether connection information is deleted according to the communication state in the main communication concerning the embodiment.

Explanation of symbols

10 Control unit (detection means, storage control means)
11 RAM (temporary storage means)
12 ROM
13 Nonvolatile memory (storage means)
14 Wireless communication devices (main communication means, sub-communication means)
20 application section 21 security control section 22 network control section 23 operation port control section (first setting means to ninth setting means)
24 file control unit 25 memory control unit 26 system control unit 27 OS unit 28 network protocol 29 wireless communication device driver 30 security information D1 subordinate device (subordinate side communication device)
P, P1, P2, P3 Main device (main side communication device)

Claims (21)

A slave-side communication device comprising main communication means for performing first wireless communication by encrypting information including identification information and communication data for identifying each other between two communication devices having a master-slave relationship,
Detecting means for detecting a main communication device connectable to the subordinate communication device among a plurality of main communication devices that may exist;
Connection information including the identification information used when performing wireless communication with the main communication device detected by the detection means and an encryption key used for encrypting the information is transmitted to the main communication device and the second communication device. Sub-communication means exchanged by performing wireless communication;
Temporary storage means for temporarily storing the connection information exchanged by the sub-communication means;
A communication apparatus, further comprising: a deletion unit that deletes the connection information stored in the temporary storage unit according to a communication state in at least one of the sub-communication unit and the main communication unit. The communication device according to claim 1, wherein the deletion unit deletes the connection information when a communication link in the sub communication unit is invalid as a communication state in the sub communication unit. The deletion means deletes the connection information when a communication link in the sub-communication means is invalid and when the communication link is invalid for a first time limit or longer. The communication apparatus according to 1 or 2. A first setting means for presetting the first time limit;
When the communication link in the sub-communication means is invalid and the state in which the communication link is invalid continues for the first time limit set by the first setting means, the deleting means is the connection information The communication device according to claim 3, wherein the communication device is deleted. The deletion means, as a communication state in the sub-communication means, when the communication link in the sub-communication means is valid and when the communication link is valid continues for a second time limit or more, It deletes. The communication apparatus as described in any one of Claims 1 thru | or 4 characterized by the above-mentioned. A second setting means for presetting the second time limit;
When the communication link in the sub-communication unit is valid and the state in which the communication link is valid continues for the second time limit set by the second setting unit, the deletion unit is The communication device according to claim 5, wherein the communication device is deleted. The communication according to any one of claims 1 to 6, wherein the deletion unit deletes the connection information as a communication state in the main communication unit according to communication traffic in the main communication unit. apparatus. Further comprising third setting means for presetting whether to delete the connection information according to the communication traffic;
The deletion unit is configured to delete the connection information according to the communication traffic when the third setting unit sets deletion of the connection information according to the communication traffic. Item 8. The communication device according to Item 7. The communication according to any one of claims 1 to 8, wherein the deletion unit deletes the connection information as a communication state in the main communication unit according to an error rate in the main communication unit. apparatus. A fourth setting means for presetting whether to delete the connection information according to the error rate;
The deletion unit deletes the connection information according to the error rate when the third setting unit sets deletion of the connection information according to the error rate. Item 10. The communication device according to Item 9. The communication according to any one of claims 1 to 10, wherein the deletion unit deletes the connection information according to a communication speed in the main communication unit as a communication state in the main communication unit. apparatus. A fifth setting means for presetting whether to delete the connection information according to the communication speed;
The deletion means deletes the connection information according to the communication speed when the fifth setting means sets that the connection information is deleted according to the communication speed. Item 12. The communication device according to Item 11. The said deletion means deletes the said connection information, when the line | wire in the said main communication means is cut | disconnected as the communication state in the said main communication means. Communication equipment. A sixth setting means for setting in advance whether or not to delete the connection information when the line is disconnected;
The deletion means sets the connection information when the line in the main communication means is disconnected, when the sixth setting means sets the deletion of the connection information when the line is disconnected. The communication device according to claim 13, wherein the communication device is deleted. The said deletion means deletes the said connection information, when a predetermined state continues as a communication state of the said main communication means more than a fixed time, The connection information as described in any one of Claims 7 thru | or 14 characterized by the above-mentioned. Communication device. A seventh setting means for presetting the predetermined time;
The communication apparatus according to claim 15, wherein the deletion unit deletes the connection information when the predetermined state continues for the predetermined time set by the seventh setting unit. And further comprising an eighth setting means for presetting the connection allowable effective period,
The deletion means deletes the connection information when the state in which the line is connected continues for the connection allowable effective period set by the eighth setting means. The communication device according to any one of 16. Storage means capable of storing the connection information;
Ninth setting means for presetting whether to store the connection information in the storage means;
The storage control means for storing the connection information in the storage means when the ninth setting means is set to store the connection information in the storage means. The communication device according to any one of 17. The communication device according to any one of claims 1 to 18, wherein the main communication unit performs first wireless communication in accordance with a WUSB (Wireless Universal Serial Bus) standard. The communication device according to any one of claims 1 to 19, wherein the sub-communication unit performs second wireless communication by NFC (Near Field Communication). This is realized by a slave communication device having a main communication means for performing first wireless communication by encrypting information including identification information for identifying each other and communication data between two communication devices having a master-slave relationship. A communication method,
The slave communication device includes a detection unit, a sub-communication unit, a storage control unit, and a deletion unit,
A detecting step of detecting a main communication device connectable to the subordinate communication device among the plurality of main communication devices that may be present;
The sub-communication means obtains connection information including the identification information used when performing wireless communication with the main-side communication device detected in the detection step and an encryption key used for encrypting the information. A sub-communication step for exchanging by performing second wireless communication with the communication device;
A storage control step in which the storage control means temporarily stores the connection information exchanged in the sub-communication step in a temporary storage means;
The deletion unit includes a deletion step of deleting the connection information stored in the temporary storage unit according to a communication state in at least one of the sub-communication unit and the main communication unit. Communication method.

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