JP2014168130A - Network switching information request device, network switching information notification device and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To contribute to appropriate provision of resumption of a session for interruption of a session due to network switching.SOLUTION: A network switching information request device includes a signal generation section for generating a NW switching information request message S12 requesting notification of generation of switching of network interfaces IFa, IFb on the WAN side. The NW switching information request message S12 is transmitted for a NW switching information notification device (mobile router 5) which notifies generation of switching of network interfaces IFa, IFb.

Description

  The present invention relates to a network switching information request device, a network switching information notification device, and a computer program.

  Conventionally, a mobile router 100 shown in FIG. 3 is known. The mobile router 100 has network interfaces IFa and IFb on the WAN (Wide Area Network) side and a network interface IFc on the LAN (Local Area Network) side, and performs routing between the WAN and the LAN. In the example of FIG. 3, on the WAN side, the network interface IFa can be connected to the base station 201 of the LTE network, and the network interface IFb can be connected to the base station 202 of the WiMAX network. On the other hand, on the LAN side, the network interface IFc can be connected to the terminal 300. For example, a wireless LAN such as WiFi is known as the network interface IFc.

  In FIG. 3, the mobile router 100 has a function of automatically switching the WAN to be connected according to the network state on the WAN side. For example, in the case of connection to the base station 201 of the LTE network, the connection is automatically switched to the base station 202 of the WiMAX network when communication between the base stations 201 occurs or when the quality measurement result is bad. Then, since the network interface to be used is switched from the network interface IFa (IP address A) to the network interface IFb (IP address B) on the WAN side of the mobile router 100, the IP address changes.

  When the change of the IP address on the WAN side in the mobile router 100 described above occurs, the session in which the terminal 300 is communicating cannot be continued, and a session disconnection occurs (for example, see Non-Patent Document 1). Non-Patent Document 1 proposes a mechanism in which a home agent device (Home Agent) is provided on a network and the IP address is not changed by the mobile IP even when the network is switched.

Yosuke Fukuyama, Hidekazu Suzuki, Watanabe, “Proposal of a Method for Seamlessly Moving Between Mobile Phone Network and Wireless LAN in IPv4 Mobile Communication”, Proceedings of Multimedia, Distributed, Cooperation and Mobile (DICOMO2011) Symposium, Vol.2011 , No.1, pp.1115-1120, Jul.2011.

  When the switching of the network on the WAN side in the mobile router described above occurs, the session of the terminal is generally disconnected, but it is necessary to wait until the terminal communication request times out before the session of the terminal is resumed. For this reason, it is conceivable that by notifying the terminal that the switching of the network on the WAN side has occurred, the terminal can promptly perform the session restart operation in response to the session restart.

  However, depending on the application or session used by the terminal, the session may not be disconnected even if the IP address changes, and the session resumption operation may not be performed. For this reason, every time the WAN-side network is switched, if the network switching is notified to the terminal via a wireless line, there is a case where it is a useless notification, and the utilization efficiency of the wireless resource is deteriorated.

  The present invention has been made in consideration of such circumstances, and can contribute to appropriately providing an opportunity for resuming a session due to session disconnection due to network switching, a network switching information requesting device, a network switching information notifying device, and It is an object to provide a computer program.

  In order to solve the above problems, a network switching information requesting apparatus according to the present invention includes a first network interface and a plurality of second network interfaces that input and output IP packets between the first network interface and the first network interface. A network switching information requesting device connected to a network switching information notifying device comprising: a signal generating unit for creating a network switching notification request message for requesting notification of occurrence of switching of the second network interface; The network switching notification request message is transmitted to the network switching information notification device that notifies the occurrence of switching of the second network interface.

  In the network switching information requesting device according to the present invention, the network switching notification request message is an IP address of the network switching information requesting device used as a destination of the network switching notification request message, or of the network switching information requesting device. It has an IP address and a port number.

  In the network switching information requesting device according to the present invention, the network switching notification request message includes a source IP address and a source port number of a TCP packet to be transmitted upon detection of a TCP SYN packet in the network switching information requesting device. It is characterized by that.

  In the network switching information requesting apparatus according to the present invention, the network switching notification request message includes a transmission source IP address and a transmission source port number of a packet transmitted from an application of the network switching information requesting apparatus.

  In the network switching information requesting device according to the present invention, as a destination of the network switching notification request message, a DHCP offer source IP address, an IP address described in a DHCP offer option, an IP address described in DHCP Ack, Alternatively, a multicast IP address is used.

  In the network switching information requesting device according to the present invention, the network switching information notifying device is switched to the network switching information notifying device only when information indicating that the network switching notification request message can be received is received from the network switching information notifying device. A notification request message is transmitted.

  The network switching information notifying device according to the present invention includes a first network interface connected to the network switching information requesting device, and a plurality of second network interfaces that input and output IP packets between the first network interface and the first network interface. An analysis unit that analyzes IP packets input to and output from each network interface and outputs packet analysis information indicating an IP address corresponding to the network switching information requesting device relating to the analyzed IP packet; A signal analysis unit that outputs a request IP address included in a network switch notification request message received from the network switch information request device; records the packet analysis information and the request IP address; A management unit that obtains and outputs an IP address corresponding to the network switching information requesting device that matches the requested IP address from the record, and a network switching that uses the IP address output from the management unit as a destination. And a creation unit for creating a notification message, wherein the network switching notification message is transmitted from the first network interface.

  The network switching information notification apparatus according to the present invention is characterized in that information indicating that the network switching notification request message can be received is transmitted to the network switching information request apparatus.

  A computer program according to the present invention is a network connected to a network switching information notification device having a first network interface and a plurality of second network interfaces that input and output IP packets between the first network interface. A computer program for performing network switching information request processing in a switching information requesting apparatus, wherein the signal generating step generates a network switching notification request message for requesting notification of occurrence of switching of the second network interface; A computer for causing the computer to execute a transmission step of transmitting the network switching notification request message to the network switching information notification device that notifies the occurrence of switching of the two network interfaces. Characterized in that it is a program.

  A computer program according to the present invention includes a first network interface connected to a network switching information requesting device, and a plurality of second network interfaces that input and output IP packets between the first network interface. A computer program for performing network switching information notification processing in a switching information notification device, analyzing IP packets input to and output from each network interface, and assigning an IP address corresponding to the network switching information requesting device relating to the analyzed IP packet An analysis step of outputting packet analysis information indicating; a signal analysis step of outputting a request IP address included in a network switching notification request message received from the network switching information requesting device; Management that records the packet analysis information and the requested IP address, and when the network switching information is input, obtains and outputs the IP address corresponding to the network switching information requesting device that matches the requested IP address from the record A step of creating a network switching notification message destined for the IP address output from the management step; and a transmission step of causing the computer to transmit the network switching notification message from the first network interface. It is a computer program for making it happen.

  According to the present invention, there is an effect that it is possible to contribute to appropriately providing an opportunity to resume a session with respect to a session disconnection due to network switching.

It is a block diagram which shows the structure of the terminal 1 and the mobile router 5 which concern on one Embodiment of this invention. It is explanatory drawing which shows the structural example of the communication network system which concerns on one Embodiment of this invention. It is explanatory drawing which shows the structural example of the conventional communication network system.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing configurations of a terminal 1 and a mobile router 5 according to an embodiment of the present invention. FIG. 2 is an explanatory diagram showing a configuration example of the communication network system according to the embodiment. In addition, about the structure of the terminal 1 shown in FIG. 1, only the part corresponding to the network switching information request | requirement apparatus which concerns on this invention is shown. Hereinafter, the present embodiment will be described with reference to FIGS. 1 and 2.

  In FIG. 2, the mobile router 5 includes WAN side network interfaces IFa and IFb and a LAN side network interface IFc, and performs routing between the WAN and the LAN. The mobile router 5 has a function of automatically switching the WAN to be connected according to the network state on the WAN side. For example, in the case of connection to the base station 201 of the LTE network, the connection is automatically switched to the base station 202 of the WiMAX network when communication between the base stations 201 occurs or when the quality measurement result is bad. As a result, since the network interface to be used is switched from the network interface IFa (IP address A) to the network interface IFb (IP address B) on the WAN side of the mobile router 5, an IP address change occurs. This is the same as the conventional mobile router 100 shown in FIG.

  In FIG. 1, a terminal 1 includes a request unit 2, a signal generation unit 3, and a network interface IFm (IP address D). The mobile router 5 includes a routing unit 10, an analysis unit 11, a management unit 12, a creation unit 13, a signal analysis unit 14, and network interfaces IFa (IP address A), IFb (IP address B), and IFc (IP address C). . The network interfaces IFa and IFb are WAN side network interfaces, and the network interfaces IFc and IFm are LAN side network interfaces.

  First, the terminal 1 will be described. The request unit 2 outputs the request information S11 to the signal generation unit 3. The request information S11 indicates a set of an IP address and a port number for requesting the NW switching notification message. In the present embodiment, the IP address is the IP address D of the network interface IFm. The NW switching notification message is a message notifying that switching of the network on the WAN side has occurred. An example of creating the request information S11 is given below.

(Request information creation example 1)
When the detection information indicating that the TCP SYN packet is detected is input, the request unit 2 outputs the source IP address (IP address D) and source port number of the TCP packet to be transmitted as the request information S11. .

(Request information creation example 2)
When detection information indicating activation of an application in which a session disconnection occurs due to switching of the WAN-side network is input to the request unit 2, a transmission source IP address (IP address D) and transmission source of a packet transmitted from the application The port number is output as request information S11.

(Request information creation example 3)
When the request unit 2 receives detection information (for example, DHCP offer detection information (when DHCP request is transmitted or DHCP ACK is detected)) indicating that the IP address D is assigned to the terminal 1, the request unit 2 transmits the information from the terminal 1. The source IP address (IP address D) of the received packet is output as request information S11. In this case, the NW switching notification message is always sent to the terminal 1. Therefore, the request of the NW switching notification message is switched on a terminal basis.

  Upon receiving the request information S11, the signal generator 3 generates an NW switching notification request message S12. The NW switching notification request message S12 has a predetermined format. The NW switching notification request message S12 stores request information S11 (source IP address, source port number). The signal generation unit 3 outputs the generated NW switching notification request message S12 to the network interface IFm. As a result, the NW switching notification request message S12 is received by the network interface IFc of the mobile router 5 via the network interface IFm.

The destination information of the NW switching notification request message S12 is acquired in advance. For example, the notification is made from the mobile router 5 when the terminal 1 is connected to the mobile router 5. Alternatively, it is fixedly set in advance for the terminal 1. Alternatively, the following IP addresses can be used.
-DHCP offer source IP address (DHCP server IP address)
・ IP address written in DHCP offer option ・ IP address written in DHCP Ack ・ Multicast IP address

  Next, the mobile router 5 will be described. The signal analyzer 14 receives the NW switching notification request message S12 received by the network interface IFc from the network interface IFc. The signal analysis unit 14 acquires request information S11 (source IP address, source port number) from the NW switching notification request message S12 according to a predetermined format. The signal analysis unit 14 outputs the acquired request information S11 to the management unit 12.

  The routing unit 10 routes IP packets (hereinafter referred to as packets).

  The analysis unit 11 captures a packet that flows between the routing unit 10 and the network interface IFa and a packet that flows between the routing unit 10 and the network interface IFb. Then, the analysis unit 11 analyzes the header information of the captured packet, and outputs packet analysis information S <b> 1 that is an analysis result to the management unit 12.

  The packet analysis information S1 related to the packet from the LAN side (terminal) to the WAN side (server that is the communication partner of the terminal) includes the IP address of the transmission source, the port number of the transmission source, and the network interface ( Identification information on the LAN side and WAN side) is included. The packet analysis information S1 regarding the packet from the WAN side (server which is the communication partner of the terminal) to the LAN side (terminal) includes the IP address of the transmission destination, the port number of the transmission destination, and the network interface ( Identification information on the LAN side and WAN side) is included.

  Based on the packet analysis information S1 received from the analysis unit 11, the management unit 12 records the network interface to be used for each terminal 1 (IP address) and for each session (port number). For example, a management table is provided, and information in the packet analysis information S1 is organized and recorded in the management table.

  Further, the management unit 12 records the request information S11 (source IP address, source port number) received from the signal analysis unit 14. For example, a request management table is provided, and information in the request information S11 is organized and recorded in the request management table. The information in the request information S11 is a pair of a transmission source IP address and a transmission source port number, or a transmission source IP address.

  In addition, network switching information (NW switching information) is input to the management unit 12. The NW switching information is information for notifying that switching of the WAN to which the mobile router 5 is connected has occurred. Specifically, the NW switching information in FIG. 2 is information for notifying that switching of the base station to which the mobile router 5 is connected has occurred between the base station 201 of the LTE network and the base station 202 of the WiMAX network. is there. Alternatively, the NW switching information is information notifying that the session has expired. The NW switching information is notified to the management unit 12 from a device that measures the quality of each WAN and selects a good WAN, or a device that reconnects when a communication disconnection occurs.

  When receiving the NW switching information, the management unit 12 outputs the NW switching notification destination information S2 to the creating unit 13. The NW switching notification destination information S2 is information on a destination to which the NW switching notification message is transmitted. The terminal 1 (IP address) and the session (port) using the network interface of the WAN in which the switching notified by the NW switching information has occurred. Number).

  Based on the record (for example, management table) of the packet analysis information S1, the management unit 12 examines a set of a terminal 1 (IP address) and a session (port number) that uses the WAN network interface in which switching has occurred. Next, the management unit 12 checks whether information matching the check result (IP address, port number) exists in the request information S11 record (for example, the request management table). The management unit 12 outputs the combination of the transmission source IP address and the transmission source port number or the transmission source IP address discovered from the record of the request information S11 as the NW switching notification destination information S2.

  The creation unit 13 creates an NW switching notification message S3. The NW switching notification message S3 is a message for notifying that the switching of the WAN has occurred to the destination (IP address or a combination of the IP address and the port number) indicated by the NW switching notification destination information S2. .

  The creation unit 13 outputs the NW switching notification message S3 to the network interface IFc. As a result, the NW switching notification message S3 is transmitted to the destination terminal 1 via the network interface IFc.

  According to the above-described embodiment, since the destination of the NW switching notification message S3 is determined based on the request information S11 from the terminal 1, the NW switching is performed only for the session that requires the NW switching notification message S3 in the terminal 1. A notification message S3 is transmitted. Thereby, it can contribute to providing the opportunity of session resumption with respect to the session disconnection by network switching appropriately.

  As described above, the creating unit 13 does not distribute the NW switching notification message S3 as push-type information, but may return the NW switching notification message S3 when there is some access from the destination terminal 1 ( Pull-type information distribution). However, when more immediacy is desired, it is preferable that the creation unit 13 distributes the NW switching notification message S3 as push-type information.

  When the mobile router 5 performs conversion between the global IP address on the WAN side and the local IP address on the LAN side, the mobile router 5 corresponds to the terminal 1 based on the information on the IP address conversion. Add a function to obtain an IP address.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

  For example, information indicating that the NW switching notification request message S12 can be received may be transmitted from the mobile router 5 to the terminal 1 in advance. For example, the mobile router 5 multicasts a request receivability flag indicating that the NW switching notification request message S12 can be received. Examples of the request receivable flag include a method of adding to a beacon transmitted by a WiFi access point of a wireless LAN, a transmission method by multicast such as MBMS in LTE, and a method of adding to a DHCP offer. The terminal 1 transmits the NW switching notification request message S12 to the mobile router 5 only when receiving the request receivable flag. Thereby, when there are various types of mobile routers and some of them cannot receive the NW switching notification request message S12, it is possible to prevent the terminal 1 from sending the NW switching notification request message S12 unnecessarily. .

  In the embodiment described above, the terminal using the WAN network interface in which switching has occurred is set as a candidate for the destination of the NW switching notification message. However, all the terminals connected to the mobile router 5 are candidates for the destination of the NW switching notification message. It is good. In this case, the packet analysis information only needs to indicate at least the IP address corresponding to the terminal. Then, the management unit 12 outputs, as NW switching notification destination information S2, an IP address corresponding to a terminal included in the packet analysis information record and a transmission source IP address included in the request information record.

  In the above-described embodiment, the mobile router is exemplified as an example of the network switching device. However, the present invention is not limited to the mobile router, and can be applied to various network switching devices.

Further, by recording a program for realizing the function of each unit shown in FIG. 1 on a computer-readable recording medium, causing the computer system to read and execute the program recorded on the recording medium, network switching information is obtained. Request processing may be performed. Here, the “computer system” may include an OS and hardware such as peripheral devices.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Terminal (network switching information request apparatus), 2 ... Request part, 3 ... Signal generation part, 5 ... Mobile router (network switching information notification apparatus), 10 ... Routing part, 11 ... Analysis part, 12 ... Management part, 13 ... Creation unit, 14 ... Signal analysis unit, IFa, IFb, IFc, IFm ... Network interface

Claims (10)

A network switching information requesting device connected to a network switching information notifying device having a first network interface and a plurality of second network interfaces that input and output IP packets between the first network interface;
A signal generation unit for creating a network switching notification request message for requesting notification of occurrence of switching of the second network interface;
Causing the network switching information notification device to notify the occurrence of switching of the second network interface to transmit the network switching notification request message;
A network switching information requesting device characterized by that.   The network switching notification request message has an IP address of the network switching information requesting device used as a destination of the network switching notification request message, or an IP address and a port number of the network switching information requesting device. The network switching information requesting device according to claim 1.   3. The network switching notification request message includes a transmission source IP address and a transmission source port number of a TCP packet to be transmitted upon detection of a TCP SYN packet in the network switching information requesting device. Network switching information request device.   3. The network switching information requesting device according to claim 2, wherein the network switching notification request message includes a transmission source IP address and a transmission source port number of a packet transmitted from an application of the network switching information requesting device.   As a destination of the network switching notification request message, a source IP address of DHCP offer, an IP address described in an option of DHCP offer, an IP address described in DHCP Ack, or a multicast IP address is used. The network switching information requesting device according to any one of claims 1 to 4.   The network switching notification request message is transmitted to the network switching information notification device only when information indicating that the network switching notification request message can be received is received from the network switching information notification device. Item 6. The network switching information requesting device according to any one of Items 1 to 5. A network switching information notifying device having a first network interface connected to a network switching information requesting device and a plurality of second network interfaces for inputting and outputting IP packets between the first network interface;
An analysis unit that analyzes IP packets input to and output from each network interface, and outputs packet analysis information indicating an IP address corresponding to the network switching information requesting device relating to the analyzed IP packet;
A signal analyzer that outputs a request IP address included in the network switching notification request message received from the network switching information requesting device;
The packet analysis information and the requested IP address are recorded, and when network switching information is input, an IP address corresponding to the network switching information requesting device that matches the requested IP address is obtained from the record and output. The management department,
A creation unit for creating a network switching notification message destined for the IP address output from the management unit,
Causing the network switch notification message to be transmitted from the first network interface;
A network switching information notification device characterized by the above.   8. The network switching information notification apparatus according to claim 7, wherein information indicating that the network switching notification request message can be received is transmitted to the network switching information request apparatus. Network switching information in a network switching information requesting device connected to a network switching information notifying device having a first network interface and a plurality of second network interfaces that input and output IP packets between the first network interface A computer program for request processing,
A signal generation step of creating a network switching notification request message for requesting notification of occurrence of switching of the second network interface;
A transmission step of causing the network switching information notification device notifying the occurrence of switching of the second network interface to transmit the network switching notification request message;
A computer program for causing a computer to execute. Network switching information in a network switching information notifying device having a first network interface connected to the network switching information requesting device and a plurality of second network interfaces that input and output IP packets between the first network interfaces A computer program for performing notification processing,
An analysis step of analyzing an IP packet input / output to / from each network interface and outputting packet analysis information indicating an IP address corresponding to the network switching information requesting apparatus relating to the analyzed IP packet;
A signal analysis step of outputting a requested IP address included in the network switching notification request message received from the network switching information requesting device;
The packet analysis information and the requested IP address are recorded, and when network switching information is input, an IP address corresponding to the network switching information requesting device that matches the requested IP address is obtained from the record and output. Administrative steps;
A creation step of creating a network switching notification message destined for the IP address output from the management step;
Transmitting the network switching notification message from the first network interface;
A computer program for causing a computer to execute.

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