WO2011027405A1

WO2011027405A1 - Communication device

Info

Publication number: WO2011027405A1
Application number: PCT/JP2009/004392
Authority: WO
Inventors: 小堺康之
Original assignee: 株式会社東芝
Priority date: 2009-09-04
Filing date: 2009-09-04
Publication date: 2011-03-10

Abstract

When an application communicates using an interface (101), the processing unit (103) of a communication device (10) outputs first socket information that includes application identifiers and the IP address of the interface (101), and when an interface (102) is connected to a network, the processing unit outputs second socket information that includes application identifiers and the IP address of the interface (102). A determining unit (105) determines that an application specified by an application identifier included in both the first and second socket information is a roaming-capable application, and determines that an application specified by an application identifier included in the first socket information but not in the second socket information is a roaming-incapable application. In the case that a roaming-incapable application is included, the processing unit (103) will not switch interfaces.

Description

Communication device

The present invention relates to a communication device.

As a communication device, there is a device that includes a plurality of interfaces and can switch the interfaces. (Patent Document 1)
For example, when the communication apparatus moves, the radio wave of the network connected to one interface is weakened, so the interface may be switched to an interface connected to a network with strong radio waves. There are two types of applications of the communication device: an application that can continue communication (application that can roam) and an application that cannot continue communication (application that cannot roam) when the interface is switched.

In a conventional communication device, when an application that cannot be roamed is operating at the timing when the interface is switched, communication of the application that cannot be roamed is stopped against the intention of the user of the communication device by switching the interface. was there.

JP 2006-60579 A

The present invention aims to prevent communication of an application from being stopped against the user's intention.

In order to achieve the above object, a communication apparatus according to an embodiment of the present invention is a communication apparatus that communicates with another apparatus via a network, and includes a first interface and a second interface that can be connected to the network. Outputting identification information including an interface, an application identifier for identifying an application, and an interface identifier for identifying an interface used by the application, a processing unit for switching an interface used for communication by the application, and the processing unit Based on the identification information that is output, it is a roamable application that can continue communication even when the interface used by the application is switched, or roaming that cannot continue communication when the interface used by the application is switched. A determination unit that determines whether the application is an application, and when the application communicates using the first interface, the processing unit includes an application identifier that identifies the application and the first interface. First identification information including a first interface identifier to be identified is output, and when the second interface is connected to a network, an application identifier and a second interface to identify an application capable of roaming are identified. The second identification information including the second interface identifier is output, and the determination unit can roam the application specified by the application identifier included in both the first identification information and the second identification information. It is determined that the application is Determining that the application identified by the application identifier not included in the second identification information is an application that cannot be roamed, and the processing unit determines that the application is not roaming. When a possible application is included, the interface used for communication by the application is not switched from the first interface to the second interface.

According to the present invention, it is possible to prevent communication of an application from being stopped against the user's intention when the interface is switched.

Diagram showing communication system Diagram showing communication device Figure showing socket information Diagram showing part of interface metric and routing table The figure which shows the operation | movement method of the communication apparatus of Example 1. Diagram showing communication device The figure which shows the operation | movement method of the communication apparatus of Example 2. Figure showing part of the routing table The figure which shows the communication apparatus of Example 3. The figure which shows the operation | movement method of the communication apparatus of Example 3.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 is a diagram illustrating a communication system according to the first embodiment. The communication device 10 of the communication system includes an interface 101 and an interface 102. The communication device 10 can communicate with the communication device 60 and the communication device 70 via the wireless LAN 80 and the Internet 85 using the interface 101. The communication apparatus 10 can communicate with the communication apparatus 60 and the communication apparatus 70 via the cellular network 90 and the Internet 85 using the interface 102.

For example, before the communication device 10 switches from communication using the interface 101 to communication using the interface 102, an application operating in the communication device 10 is an application that can continue communication (an application that can roam). It is determined whether the application is an application that cannot be continued (an application that cannot be roamed). If the application is an application that cannot be roamed, communication from the interface 101 to communication using the interface 102 is performed for the application. The communication using the interface 101 is continued without switching.

Here, the wireless LAN 80 is a network to which the interface 101 can be connected, and is connected to the Internet 85. The cellular network 90 is a network to which the interface 102 can be connected, and is connected to the Internet 85. The Internet 85 is connected to the communication device 60 and the communication device 70.

For example, when the interface 101 is connected to a wireless LAN, when the radio wave of the wireless LAN 80 becomes weak (for example, lower than a certain threshold), the communication device 10 detects that the radio wave has weakened. Then, it is determined whether to switch the interface from the interface 101 to the interface 102. When it is determined to switch, the communication device 10 switches from the interface 101 to the interface 102.

FIG. 2 is a block diagram showing the communication device 10.

The communication apparatus 10 includes a roaming application 104A and a non-roaming application 104B. Both the roamable application 104A and the non-roamable application 104B can communicate with the communication device 60 and the communication device 70 via the wireless LAN 80 and the Internet 85 using the interface 101. Can be communicated with the communication device 60 and the communication device 70 via the cellular network 90 and the Internet 85. The roamable application 104A can continue communication even after the interface used for communication is switched from the interface 101 to the interface 102. On the other hand, when the application 104B that cannot roam is switched from the interface 101 to the interface 102, communication cannot be continued.

The application 104A capable of roaming is, for example, a VoIP application. The application 104B that cannot be roamed at the present time is, for example, mail software or a web browser. Note that these non-roamable applications 104B can become roamable applications as future technology advances. When the roaming application 104A is communicating using the interface 101, the processing unit 103 uses an application identifier (for example, process ID) that identifies the application 104A in response to a request from the determination unit 105 and the interface 101. The first socket information (first identification information) including the first IP address (first interface identifier) that identifies the first IP address is output to the determination unit 105. In addition, when the non-roamable application 104B is communicating using the interface 101, the processing unit 103 responds to the request from the determination unit 105 with an application identifier that identifies the application 104B and the first assigned to the interface 101. The first socket information including one IP address is output to the determination unit 105. Here, the first socket information is socket information including the first IP address of the interface 101. As will be described later, in this embodiment, the determination unit 105 acquires all socket information from the processing unit 103 before and after connecting the interface 102 to the cellular network 90. Regardless of the time point at which the determination unit 105 acquires socket information, socket information including the first IP address assigned to the interface 101 is set as first socket information. When the interface 102 is connected to the cellular network 90, the processing unit 103 receives the application identifier that identifies the roaming application 104A and the second IP address (second interface identifier) assigned to the interface 102. The included second socket information (second identification information) is output to the determination unit 105. Here, the second socket information is socket information including the second IP address of the interface 102. Regardless of the time point at which the determination unit 105 acquires the socket information, the socket information including the second IP address of the interface 102 is set as the second socket information. The roamable application 104A can detect when the interface 102 is connected to the cellular network. When detecting the connection, the roamable application 104A causes the processing unit 103 to generate socket information. When the determination unit 105 requests socket information, the processing unit 103 outputs the socket information to the determination unit 105. Note that the determination unit 105 may periodically acquire socket information from the processing unit 103.

On the other hand, even if the determination unit 105 requests socket information after the interface 102 is connected to the cellular network 90, the processing unit 103 and the application identifier that identifies the application 104B that cannot roam and the second interface 102 The second socket information including the IP address is not output to the determination unit 105. The non-roamable application 104B does not communicate using the interface 102 even if the interface 102 is connected to the cellular network. Therefore, since there is no instruction for generating the second socket information to the processing unit 103 from the application 104B, the processing unit 103 does not generate the second socket information including the application identifier of the application 104B.

The determination unit 105 determines whether an application operating on the communication device 10 is a roamable application or a non-roamable application using all socket information acquired before and after connecting the interface 102 to the cellular network 90. To do. That is, as described above, the determination unit 105 can acquire the first socket information and the second socket information including the application identifier of the roamable application 104A. On the other hand, the determination unit 105 can acquire the first socket information including the application identifier of the application 104B that cannot be roamed, but cannot acquire the second socket information including the application identifier of the application 104B that cannot be roamed. Therefore, the application specified by the application identifier included in each of the first socket information and the second socket information can be specified as the roamable application 104A, and is specified by the application identifier included only in the first socket information. Can be identified as the application 104B that cannot be roamed.

When the determination unit 105 determines that the application running on the communication device does not include the roaming application 104B, the processing unit 103 receives an instruction from the determination unit 105 and uses the interface 101 for an interface used by the application for communication. Switch to the interface 102. Further, when it is determined that the application operating in the communication apparatus 10 includes the application 104B that cannot be roamed, the interface is not switched from the interface 101 to the interface 102.

Next, the detailed configuration of the communication device 10 will be described.

2, the communication apparatus 10 includes an interface 101, an interface 102, a processing unit 103,

applications

104A and 104B, a determination unit 105, an application management unit 106, and a setting storage unit 107.

In the communication device 10, first, it is assumed that the interface 101 is connected to the wireless LAN 80. At this time, both the

applications

104A and 104B communicate with the communication device 60 or the communication device 70 via the wireless LAN 80 and the Internet 85 using the interface 101.

For example, when the radio wave of the wireless LAN 80 received by the interface 101 of the communication apparatus 10 becomes weak, the determination unit 105 of the communication apparatus 10 determines whether to switch the interface from the interface 101 to the interface 102. When the determination unit 105 determines to switch the interface, the communication device 10 switches from the interface 101 to the interface 102 and communicates with the communication device 60 or the communication device 70 via the cellular network 90 and the Internet 85.

The

applications

104A and 104B generate data and output the data to the processing unit 103. For example, when the application 104A is VoIP, the data is voice information. When the roaming application 104A detects that the interface 102 is connected to the cellular network 90, the application 104A causes the processing unit 103 to generate a packet including the second IP address that identifies the interface 102, The communication apparatus 60 of the communication partner is notified.

The processing unit 103 performs a protocol process on the data output from the application 104 to generate a packet. The processing unit 103 transmits the generated packet from the interface 101 or the interface 102 to the communication device 60 or the communication device 70. The processing unit 103 also determines an output interface using a routing table described later stored in the setting storage unit 107. In addition, the processing unit 103 generates first socket information or second socket information according to an instruction from the application 104. In addition, the processing unit 103 outputs the first socket information and the second socket information to the determination unit 105.

Here, the socket information will be described. FIG. 3 is a diagram illustrating socket information. The socket information is composed of a set of protocol type, own address, own port number, counterpart address, counterpart port number, and process ID. The protocol type indicates a protocol used by the application for communication. For example, TCP or UDP. The own address indicates an IP address assigned to the interface used by the application for communication. The own port number indicates the TCP or UDP port number used by the application for communication. The partner address and partner port number indicate the IP address of the interface of the communication device of the communication partner and the TCP or UDP port number used for communication, respectively. The process ID is an identifier that identifies an application.

Here, the setting storage unit 107 will be described. The setting storage unit 107 stores a route table set in the communication device and interface metrics of each interface included in the communication device.

Fig. 4 (a) shows an example of interface metrics. In the example of FIG. 4A, the interface metrics of the interface 101 and the interface 102 are 20, 30, respectively.

Fig. 4 (c) shows an example representing a part of the route table. The route table is composed of a plurality of routes. A route is composed of a set of destination, netmask, gateway, interface, and metric. The interface included in the route table is an interface connected to the network. In particular, a route whose destination and netmask are 0.0.0.0 is referred to as a default route. The processing unit 103 determines an interface that outputs a packet by applying a longest match algorithm to the destination and netmask of each route and the destination address of the packet. As a result, when a plurality of default routes are selected, the processing unit 103 selects an interface included in the default route having a small metric as an output interface. In FIG. 4C, the route table includes two default routes, and the metrics of the route including the interface 101 and the interface 102 are 20 and 30, respectively. The route metric changes according to the value of the interface metric. In FIG. 4A, the interface metrics of the interface 101 and the interface 102 are 20 and 30, respectively. In the example of FIG. 4C, the metric of each default route has the same value as the interface metric of the interface included in each default route. In this way, the magnitude relationship of each route is the same as the magnitude relationship of the interface metrics. Note that the interface metric and the route metric need not be the same value. The path metric and interface metric can be changed independently. Therefore, in the example of FIG. 4C, the processing unit 103 transmits a packet from the interface 101 unless the application specifies an output interface.

The processing unit 103 also connects or disconnects the interfaces 101 and 102 to and from the wireless LAN 80 and the cellular network 90 according to instructions from the determination unit 105, respectively. Further, the processing unit 103 changes the value of the interface metric stored in the setting storage unit 107 in accordance with an instruction from the determination unit 105. Further, the processing unit 103 changes the metric value of the route stored in the setting storage unit 107 in accordance with the instruction of the determination unit 105. Further, when the interface 103 is connected to the network, the processing unit 103 adds a route corresponding to the interface to the route table. Further, when the interface 103 is disconnected from the network, the processing unit 103 deletes the route corresponding to the interface from the route table.

The determination unit 105 uses the socket information output from the processing unit 103 to determine whether the application 104A and the application 104B operating on the communication device 10 are roamable applications or non-roamable applications. Specifically, first, before the connection of the interface 102, the determination unit 105 acquires all socket information output by the processing unit 103. Also, the determination unit 105 acquires a process ID and a set of application names corresponding to the process ID from the application management unit 106. The application management unit 106 manages a combination of an application name and a process ID of an application running on the communication device 10. The determination unit 105 uses the socket information and information acquired from the application management unit 106 to identify an application that is communicating or preparing for communication before the interface 102 is connected. The determination unit 105 acquires all socket information from the processing unit 103 again after the interface 102 is connected. Also, all combinations of process IDs and application names are acquired from the application management unit 106. The socket information and the information acquired from the application management unit 106 are used to identify an application that is communicating or preparing for communication using the interface 102 after the interface 102 is connected. The socket information acquired before and after connection of the interface 102 includes first socket information including a process ID of a certain application, and the socket information acquired after connection of the interface 102 includes the process ID of the same application. If there is second socket information, it is determined that the application is a roamable application. In addition, an application that is communicating other than the roamable application is determined to be an application that cannot be roamed.

If only 104A is operating, the determination unit 105 determines that the application 104A operating on the communication device 10 is a roamable application and switches the interface. Specifically, the determination unit 105 causes the processing unit 103 to disconnect the interface 101 from the wireless LAN 80. On the other hand, when the application 104B is operating, the determination unit 105 determines that the application 104B is an application that cannot be roamed, and interrupts interface switching. That is, the determination unit 105 causes the processing unit 103 to disconnect the interface 102 from the cellular network 102 without disconnecting the interface 101 from the wireless LAN 80.

Next, an operation method of the communication device 10 will be described. FIG. 5 is a flowchart illustrating an operation method of the communication device 10.

In the following, it is assumed that the interface 101 is being connected to the wireless LAN 80, and the roamable application 104A and the non-roamable application 104B are in communication with the communication device 60 via the wireless LAN 80 and the Internet 85. . Further, it is assumed that the interface 102 is not connected to the cellular network 90.

First, when the communication device 10 detects that the radio wave of the wireless LAN has become low, the determination unit 105 acquires all socket information from the processing unit 103. Since the interface 101 is being connected before the interface is switched, the processing unit 103 outputs the first socket information (S1). As described above, the first socket information is socket information whose own address is the IP address of the interface 101.

Next, the determination unit 105 identifies an application corresponding to each of the first socket information acquired from the processing unit 103 (S2). In other words, the determination unit 105 acquires the combination of the application name and the process ID managed by the application management unit 106 and compares the acquired process ID with the process ID included in the first socket information, thereby including it in the first socket information. The application corresponding to the process ID to be specified is specified. As a result, the determination unit 105 specifies that the applications corresponding to the first socket information are the

applications

104A and 104B. Hereinafter, an application corresponding to socket information is defined as an application specified by an application identifier (process ID) included in the socket information.

Next, the processing unit 103 connects the interface 102 to the cellular network 90 while maintaining the connection of the interface 101 (S3). Specifically, first, the processing unit 103 sets the interface metric of the interface 102 stored in the setting storage unit 105 to a value larger than the interface metric of the interface 101. For example, in FIG. 4A, the interface metric of the interface 101 is 20, and the processing unit 103 sets the interface metric of the interface 102 to 30. Next, the determination unit 105 instructs the processing unit 103 to connect the interface 102 to the cellular network 90. Next, the processing unit 103 connects the interface 102 to the cellular network 90 according to an instruction from the determination unit 105. Next, the processing unit 103 adds a default route associated with the interface 102 to the route table. At this time, the processing unit 103 sets the metric of the default route associated with the interface 102 to 30. That is, the same value as the interface metric of the interface 102 is set. Note that the default route metric associated with the interface 102 may not be set to the same value as the interface metric of the interface 102. FIGS. 4B and 4C show route tables before and after connecting the interface 102 to the cellular network 90, respectively. When comparing the metrics of the interfaces 101 and 102, the metric of the interface 101 is smaller. Accordingly, the

applications

104A and 104B continue to communicate using the interface 101 unless a special instruction is given to the processing unit 103. In summary, in step S3, the determination unit 105 and the processing unit 103 connect the interface 102 to the cellular network 90 by a method that does not hinder communication of the application 104B that cannot roam.

Next, the determination unit 105 acquires all socket information from the processing unit 103 (S4). In the present embodiment, since the application 104A can roam, the processing unit 103 outputs the second socket information including the process ID of the application 104A to the determination unit 105.

Next, the determination unit 105 identifies an application corresponding to the acquired socket information (S5).

Next, the determination unit 105 identifies an application that operates on the communication device 10 and can roam (S6). Specifically, the determination unit 105 includes the first socket information including the process ID associated with the name of an application in the socket information acquired in S2 or S4, and the socket acquired in S4. When the second socket information including the process ID associated with the same application name exists in the information, it is determined that the application is a roamable application. In this embodiment, when the application 104A and the application 104B are operating, the determination unit 105 determines that the application 104A is a roamable application.

From step S4 to step S4, the communication device 10 determines whether or not roaming is possible for all applications in communication, until a predetermined time elapses, or is executed a predetermined number of times. Repeat S6.

Next, the determination unit 105 determines that the application cannot be roamed once from step S4 to step S6, and determines that the communicating application is an application that cannot be roamed (S7). As a result, when the application 104A and the application 104B are operating, the determination unit 105 determines that the application 104A is an application that can be roamed, and determines that the application 104B is an application that cannot be roamed.

Next, when the determination unit 105 determines that all applications running on the communication device 10 are roamable applications, the processing unit 103 switches from the interface 101 to the interface 102 according to an instruction from the determination unit 105 ( S8). For example, when the application 104A capable of roaming is operating and the application 104B not capable of roaming is not operating, switching from the interface 101 to the interface 102 is performed. Specifically, the interface 101 is disconnected from the wireless LAN 80. On the other hand, when the determination unit 105 determines that there is an application that cannot be roamed among applications operating on the communication apparatus 10, the processing unit 103 does not switch from the interface 101 to the interface 102. When the application 104 </ b> B that cannot be roamed is operating, the processing unit 103 does not switch from the interface 101 to the interface 102.

FIG. 4D shows a path table when switching from the interface 101 to the interface 102 is performed. In FIG. 4D, the default route of the interface 102 is stored, and the default route of the interface 101 is not stored.

In the first embodiment, the setting storage unit 107 stores the interface metric, but it may not be stored. In this case, in step S3, the processing unit 103 sets the default route metrics of the interfaces 101 and 102 to, for example, 20 and 30, respectively, regardless of the interface metric.

Also, in the first embodiment, the processing unit 103 does not have to have a function of determining an output interface using a path metric. Further, the processing unit 103 may not be able to set only one default route. In this case, the processing unit 103 does not add the default route to the route table in step S3. In this case, the application 104 communicates using the interface 101. In step S8, when the interface 101 is disconnected from the wireless LAN 80, the default route of the interface 101 in the setting storage unit 107 is deleted and the default route of the interface 102 is added. As a result, the application 104 communicates using the interface 102. According to the communication apparatus 10 of the present embodiment, it is possible to specify an application that can be roamed and an application that cannot be roamed. When an application that cannot roam is not operating, the interface is switched. In addition, it is possible to prevent the communication of the application from being stopped against the user's intention.

In the first embodiment, when it is determined in S7 that an application that cannot be roamed is in operation, the user is notified that the application that cannot be roamed is operating, and the interfaces 101 to 102 are instructed by the user. Whether or not to switch to may be selected. In this case, as illustrated in FIG. 6, when the communication apparatus 10A determines in S7 that an application whose application cannot be roamed is in operation, “If the interface is switched, the application is stopped. The display unit 121 displays a message such as “?”, And the input unit 120 inputs whether the user switches the display on the display unit. When the user instructs switching using the input unit 120, switching from the interface 101 to the interface 102 is performed as in S8. On the other hand, when the user instructs not to switch, switching from the interface 101 to the interface 102 is not performed.

Note that the information used by the determination unit 105 to determine whether the application running on the communication device 10 is an application that can be roamed is not limited to socket information. For example, when the application causes the processing unit 103 to execute a bind system call, the processing unit 103 sets a combination of the process ID of the application that instructed the bind system call, the type of the system call, and the IP address specified in the bind system call. You may output to the determination part 105. FIG. That is, any information including an identifier for identifying an application and an interface identifier for identifying an interface used by the application for communication may be used.

Further, in the present embodiment, it has been described that the determination unit 105 repeatedly acquires socket information from the processing unit 103 and identifies an application capable of roaming for a predetermined time. However, the timing at which the determination unit 105 acquires socket information from the processing unit 103 is not limited to this. For example, the determination unit 105 causes the processing unit 103 to monitor packets transmitted and received by the interface 101 and the interface 102 for a certain period. When the processing unit 103 detects a packet including the IP address of the interface 102, the processing unit 103 notifies the determination unit 105 of the packet. Then, when the determination unit 105 receives the packet from the processing unit 103, the determination unit 105 may acquire socket information from the processing unit 103.

In this embodiment, the interface 101 is connected to the wireless LAN 80, and the interface 102 is connected to the cellular network 90. However, the present invention is not limited to this. For example, the interface 101 and the interface 102 may be connected to the wireless LAN 80.

The communication device 10 according to the present embodiment can also be realized by using a general-purpose computer device as basic hardware. That is, the interface 101, the interface 102, the processing unit 103, the

applications

104A and 104B, the determination unit 105, the application management unit 106, and the setting storage unit 107 execute a program on the processor mounted on the computer device. Can be realized. At this time, the communication device 10 can be realized by executing the above program. At this time, the communication device 10 may be realized by installing the above-described program in a computer device in advance, or may be stored in a storage medium such as a CD-ROM or distributed through the network 30. Then, this program may be realized by appropriately installing it in a computer device. The setting storage unit 107 is realized by appropriately using a memory, a hard disk or a storage medium such as a CD-R, a CD-RW, a DVD-RAM, a DVD-R, or the like incorporated in or externally attached to the computer device. be able to.

The communication device 20 according to the second embodiment switches the interface using a method different from that of the communication device 10 according to the first embodiment. Specifically, the metric of the default route associated with the interface 101 is set to be larger than the metric of the default route associated with the interface 102 while maintaining the connection of the interface 101. As a result, the interface 101 can be switched to the interface 102 while maintaining the connection of the interface 101 with the wireless LAN 80. Also, the method for determining the roamable application and the non-roamable application according to the second embodiment is different from the method according to the first embodiment. That is, in the method for determining a roamable application according to the second embodiment, an application that meets any of the following three conditions is determined as a roamable application. The first condition is the same as the roamable application according to the first embodiment. That is, it is an application corresponding to the first socket information and an application corresponding to the second socket information. The second condition is that the application corresponds to the first socket information, and the protocol type of the socket information is TCP. The third condition is that the application corresponds to the first socket information, the protocol type of the socket information is UDP, and the socket information continues to use the interface 101 by the bind system call. Information to be included.

Next, the reason why the application corresponding to the second condition or the third condition is an application capable of roaming will be described. First, the reason for the second condition is as follows. When an application communicates using TCP, the IP address used by the application is determined when a TCP session is established. And even if the priority of the interface or route (metric) is changed, until the application disconnects the TCP session, the packet including the application data is transmitted from the interface to which the IP address at the time of establishing the TCP session is assigned. The As described above, the communication device 20 maintains the connection without disconnecting the switching-source interface 101 when switching the interface. Therefore, even if the interface 101 is switched to the interface 102 (the metric is changed), the application can continue communication using the interface 101. The reason for the third condition is as follows. When an application communicates using UDP and declares to continue using the interface 101 by a bind system call, the IP address used by the application is determined when the application is declared by the bind system call. Even if the interface or route priority (metric) is changed, the IP address at the time of the bind system call declaration is assigned to the packet including the application data until the application ends the UDP communication. Sent from the interface. Therefore, even if the application corresponding to the third condition is switched from the interface 101 to the interface 102 for the same reason as the application corresponding to the second condition, communication can be continued.

The components of the communication device 20 of the second embodiment are the same as the components of the communication device 10 of the first embodiment as shown in FIG. Here, it is assumed that the application 104B is an application that does not meet the first to third conditions and cannot be roamed.

The operation method of the communication device 20 will be described. FIG. 7 is a flowchart illustrating an operation method of the communication device 20.

S1 to S5 are the same operations as the operation method of the communication apparatus 10 of the first embodiment.

Next, a roamable application operating on the communication device 20 is specified (S26). That is, it is determined whether or not the application corresponding to the acquired socket information is an application that meets any of the first to third conditions. The first condition is the same as the method determined in the first embodiment. That is, the application corresponds to the first socket information acquired in S1 and corresponds to the second socket information acquired in S4. The second condition is that the application corresponds to the socket information in which the protocol type included in the socket information acquired in S1 or S4 is TCP and the IP address is the IP address of the interface 101. . The third condition is that the protocol type included in the socket information acquired in S4 is UDP and the application corresponds to the socket information whose IP address is the IP address of the interface 101. Here, when the own address included in the socket information is an IP address other than 0.0.0.0 and the protocol type is UDP, the application causes the processing unit 103 to execute the bind system call. It shows that.

The communication device 10 determines whether or not roaming is possible for all applications in communication, until a predetermined time has elapsed, or until a predetermined number of times have been executed, from step S4 to step S26. repeat.

Next, the determination unit 105 determines that the application cannot be roamed once from step S4 to step 26, and determines that the communicating application is an application that cannot be roamed (S27).

Next, when the determination unit 105 determines that all applications in communication with the communication device 20 are roamable applications, the processing unit 103 switches from the interface 101 to the interface 102 according to an instruction from the determination unit 105. (S28). Specifically, in order to change the interface metric of the interface 101 to be larger than the interface metric of the interface 102, the determination unit 105 outputs a new value of one or both of the interface metric of the interface 101 and the interface 102 to the processing unit 103. To do. In addition, the processing unit 103 sets the metric of the default route associated with the interface 102 in the route table stored in the setting storage unit 107 to be smaller than the metric of the default route associated with the interface 101. . For example, as shown in FIG. 10, the metric of the default route of the interface 102 is set to 10. On the other hand, when the determination unit 105 determines that an application that is not roaming is included as an application running on the communication device 20, the processing unit 103 does not switch from the interface 101 to the interface 102.

According to the communication device 20 according to the second embodiment, the same effect as that of the communication device 10 according to the first embodiment can be achieved. That is, when switching the interface, it is possible to prevent the communication of the application from being stopped against the user's intention.

Also, the communication device 20 according to the second embodiment can switch from the interface 101 to the interface 102 while maintaining the connection of the interface 101. As a result, the interface 101 can be switched to the interface 102 even when the following two applications are operating. The first application is an application corresponding to the first socket information and the protocol type of the socket information is TCP. The second application is an application corresponding to the first socket information, the protocol type of the socket information is UDP, and the socket information continues to use the interface 101 by the bind system call. It is an application including information indicating

The communication device 30 of the third embodiment is different from the first embodiment in that it determines whether or not the application is a roamable application using socket information acquired when the application is activated.

In addition, when the switching source interface and the switching destination interface are already connected by a user or the like, it is different from the first embodiment in that it is determined whether to switch the interface.

Also, the communication device 30 according to the third embodiment is different from the communication device 10 according to the first embodiment, in which the determination unit 105 determines whether the application running on the communication device is an application that can roam when the application is activated. After the determination, the application name of the roamable application is stored in the roamable application storage unit 308 without switching the interface immediately after the determination, and the roamable application storage unit 308 stores the active application and the roamable application storage unit 308. Are compared to determine whether or not the operating application is a roamable application, and the processing unit 103 switches from the interface 101 to the interface 102 based on the determination result.

As illustrated in FIG. 9, the communication device 30 includes a roamable application storage unit 308 in addition to the configuration of the communication device 30 according to the third embodiment. The roamable application storage unit 308 stores application names of roamable applications.

Hereinafter, an operation method of the communication device 30 will be described. FIG. 10 is a flowchart illustrating an operation method of the communication device 30.

Suppose that the application 104A of the communication device 30 is not activated when the operation starts. Further, it is assumed that the interface 101 is connected to the wireless LAN 80 and the interface 102 is connected to the cellular network 90. Assume that the metrics of the default route in the route table are 20 and 30 respectively for the interfaces 101 and 102 as shown in FIG.

First, the application 104A is activated (S31).

Next, the determination unit 105 acquires socket information from the processing unit 103 (S32).

Next, the determination unit 105 determines whether the application 104A is a roamable application from the socket information acquired from the processing unit 103 (S33). That is, first, the determination unit 105 acquires a combination of an application name and a process ID from the application management unit 106, and compares the process information of the socket information with each other, thereby specifying the socket information corresponding to the application 104A. Next, the determination unit 105 determines whether the first socket information (socket information including the IP address of the interface 101 as an IP address) from the IP address of the interface included in the specified socket information or the second socket information (IP Socket information including the IP address of the interface 102 as an address). Next, when the first socket information and the second socket information corresponding to the application 104A are acquired, the determination unit 105 determines that the application 104A is a roamable application. Since the application 104A is a roamable application, the first socket information and the second socket information can be acquired, and it is determined that the application is roamable. This is because the fact that the first and second socket information corresponding to the application 104A can be acquired indicates that communication is performed using both the interface 101 and the interface 102. Next, when it is determined that the application 104A is a roamable application, the roamable application storage unit 108 stores the application name of the application 104A (S34).

The communication device 30 repeats steps S32 to S34 until a predetermined time elapses or until a predetermined number of times are executed.

The communication device 30 repeats S32 to S34 each time a new application is started. Therefore, there is a possibility that application names of a plurality of roamable applications are stored in the roamable application storage unit 108.

Next, when the communication device 30 detects that the radio wave of the wireless LAN has become low and the determination unit 105 instructs switching from the interface 101 to the interface 102, the determination unit 105 receives the socket information from the processing unit 103. Is acquired (S35).

Next, the determination unit 105 specifies an application in communication by specifying an application corresponding to the socket information acquired in S35 (S36).

Next, the determination unit 105 determines whether or not the application specified in S36 is a roamable application (S37). That is, the determination unit 105 determines whether the operating application is a roamable application based on whether or not the application name of the application specified in S36 exists in the roamable application storage unit 308. Here, when both of the

applications

104A and 104B are operating, it is determined that the application 104A is an application that can roam, and the application 104B is determined to be an application that cannot be roamed.

Next, when the determination unit 105 determines that all the running applications are roamable applications, the processing unit 103 switches from the interface 101 to the interface 102 according to an instruction from the determination unit 105 (S38). For example, when the application 104A operates and the application 104B does not operate, the interface is switched. That is, the interface 101 is disconnected from the wireless LAN 80. On the other hand, when the determination unit 105 determines that the application is an application that cannot be roamed, the processing unit 103 does not switch from the interface 101 to the interface 102. For example, when the application 104B is operating, the interface is not switched.

According to the communication device 30 according to the third embodiment, the same effect as that of the communication device 10 according to the first embodiment can be achieved. That is, when switching the interface, it is possible to prevent the communication of the application from being stopped against the user's intention.

In addition, the communication device 30 according to the third embodiment prevents the communication of the application from being stopped against the user's intention when the interface is switched in a state where the switching destination interface and the switching source interface are already connected. it can.

In addition, the communication device 30 according to the third embodiment stores the roamable application in the roamable application storage unit 308 after determining whether or not the application can be roamed. It is possible to shift the switching timing. Therefore, for example, if an application that cannot be roamed and is operating at the time of determining whether or not it is a roamable application is not operating at the time of interface switching, the interface can be switched.

It should be noted that the present invention and the above-described embodiments are not limited as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. As a matter of fact, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

10, 10A, 20, 30, 60, 70 ... communication device, 101, 102 ... interface, 103 ... processing unit, 104A, 104B ... application, 105 ... determination unit, 106 ... Application management unit 107: Setting storage unit 120 ... Input unit 121 ... Display unit 80 ... Wireless LAN 85 ... Internet 90 ... Cellular network 308・ Roamable app storage

Claims

A communication device that communicates with other devices via a network,
A first interface and a second interface connectable to a network;
A processing unit that outputs identification information including an application identifier that identifies an application and an interface identifier that identifies an interface used by the application, and switches an interface used by the application for communication;
Based on the identification information output by the processing unit, it is a roamable application that can continue communication even if the interface used by the application is switched, or an application that cannot continue roaming when the interface used by the application is switched And a determination unit for determining whether or not
When the application communicates using the first interface, the processing unit includes first identification information including an application identifier that identifies the application and a first interface identifier that identifies the first interface. And when the second interface is connected to the network, second identification information including an application identifier that identifies an application that can roam and a second interface identifier that identifies the second interface Output,
The determination unit determines that an application specified by an application identifier included in both the first identification information and the second identification information is an application capable of roaming, and is included in the first identification information. Determining that the application specified by the application identifier not included in the second identification information is an application that cannot be roamed,
When the application includes an application that cannot be roamed, the processing unit does not switch an interface used for communication by the application from the first interface to the second interface.
When the processing unit starts the application, when the first interface and the second interface are connected to the network, the processing unit identifies an application identifier that identifies a roamable application, a first interface identifier, And second identification information including an application identifier for specifying the roamable application and a second interface identifier, and an application identifier for specifying an application that cannot be roamed and the first 1st identification information including the first interface identifier, or the second identification information including the second interface identifier and the application identifier specifying the application that cannot be roamed is output. ,
The determination unit determines that an application specified by an application identifier included in both the first identification information and the second identification information is an application capable of roaming, and the first identification information and the first identification information The communication apparatus according to claim 1, wherein an application specified by an application identifier not included in both pieces of identification information is determined as an application that cannot be roamed.
A first storage unit that stores a roamable application name corresponding to an application identifier that identifies the roamable application determined by the determination unit;
The determination unit determines whether an application name corresponding to an application identifier included in the identification information output by the processing unit matches a roamable application name stored in the first storage unit,
When the application name corresponding to the application identifier included in the identification information does not match the roamable application name stored in the first storage unit, the processing unit determines an interface used by the application for communication from the first interface. 3. The communication apparatus according to claim 2, wherein switching to the second interface is not performed.
An interface identifier that identifies an interface connected to the network; and a second storage unit that stores a priority corresponding to the interface identifier for communication by the application using the interface;
When the processing unit connects the second interface to a network, the second storage unit stores a second interface identifier for identifying the second interface, and the second interface. 4. The communication apparatus according to claim 3, wherein a priority lower than a priority for performing communication using the first interface is stored in correspondence with an interface identifier.
The identification information is information including a protocol type, and the determination unit is an application identified by an application identifier included in the first identification information, and the protocol type is TCP, and the first It is determined that any of the applications identified by the application identifier included in the identification information 1 and information that has been called by the bind system call and the protocol type is UDP is a roamable application. And
When the first interface and the second interface are interfaces connected to a network, the processing unit performs switching from the first interface to the second interface, 5. The communication apparatus according to claim 4, wherein the priority of the second interface is set higher than the priority of the first interface.