JP2012109837A - Network connection apparatus, address information management apparatus, network system, network connection method and network connection program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a favorable communication operation in a radio terminal device by appropriately controlling the traffic between the radio terminal device and a network.SOLUTION: A network connection apparatus 101 comprises: an inquiry information acquisition part 21 which acquires the inquiry information of a communication destination address from a specific terminal device 151 where access is permitted to a specific external network; and an inquiry information transmission part 22 which transmits the inquiry information acquired by the inquiry information acquisition part 21 to a first address information management apparatus 302 and a second address information management apparatus 301. The first address information management apparatus 302 is provided in the specific external network, searches an address corresponding to the inquiry information, and transmits response information indicating the searched address. The second address information management apparatus 301 is provided in a general external network where the specific external network is connected, searches the address corresponding to the inquiry information, and transmits the response information indicating the searched address.

Description

  The present invention relates to a network connection device, an address information management device, a network system, a network connection method, and a network connection program, and in particular, a network connection device that responds to a communication destination address inquiry from a wireless terminal device, and address information management The present invention relates to an apparatus, a network system, a network connection method, and a network connection program.

  Home gateways have been developed that have functions such as IP (Internet Protocol) packet routing and protocol conversion, and connect an internal network in a home to an external network such as the Internet.

  Conventionally, in a mobile communication system, a communication service is provided by a radio base station apparatus (hereinafter also referred to as a macro base station) that forms an area in which a cell having a radius of several hundred meters to several tens of kilometers, that is, a radio terminal apparatus can communicate. It has been.

  In recent years, due to a dramatic increase in the number of subscribers of mobile communication services and an increase in the amount of communication traffic due to data communication, subscribers and communication traffic are distributed by forming smaller radius cells, and a certain level of communication It is desirable to provide speed to users in a stable manner. In addition, in order to deal with dead zones associated with the increase in the number of buildings, it is desired to install radio base station devices on the corporate floor and in ordinary households.

  Together with these demands, the processing capability of various devices used in the radio base station apparatus has been dramatically improved, and the miniaturization of the radio base station apparatus has progressed. Collecting.

  Since the radius of the femto cell (Femto Cell) formed by this small base station (hereinafter also referred to as a femto base station) is as small as about 10 meters, the femto base station is the macro cell (Macro Cell) formed by the macro base station. It can be used in places such as homes and underground malls that are outside the service area and where it is difficult to install macro base stations.

  When such a femto base station is installed in a home, a wireless terminal device that exists in a femto cell and communicates with the femto base station, for example, transmits an IP packet between the femto base station and an external network via a home gateway. Send and receive.

  Here, when transmitting an IP packet, it is necessary to perform so-called name resolution. That is, an inquiry about an IP address corresponding to a domain name of a communication destination is made to a domain name server (hereinafter also referred to as a DNS (Domain Name System) server) that converts a domain name corresponding to a computer name on the Internet into an IP address. It is necessary to obtain the IP address of the communication destination from the domain name server.

  As an example of a configuration for routing an IP packet using such a DNS server, for example, Patent Document 1 (Japanese Patent No. 3902597) discloses the following technique. That is, the router corresponds to the IP address of the plurality of gateways by referring to the IP packet collection unit that collects data packets having the destination IP address from the terminal and the routing cache table that associates the plurality of addresses with the plurality of gateways. An IP packet transfer unit that transfers the data packet to the corresponding gateway, and a reverse query unit that collects a reply domain name corresponding to the IP address from a DNS server when the corresponding gateway is not searched from the routing cache table; Referring to the domain name routing table that associates multiple domain names with multiple gateways, the gateway search for searching for an answer gateway corresponding to the answer domain name from among the multiple gateways When, in the routing cache table, and a routing table update unit for recording the IP address in association with the answers gateway. The IP packet transfer unit transfers the data packet to the answer gateway when the corresponding gateway is not searched from the routing cache table. The routing cache table is stored in a volatile memory included in the router, and the domain name routing table is stored in a nonvolatile memory included in the router.

Japanese Patent No. 3902597

  When transmitting an IP packet, a wireless terminal device such as a mobile phone normally inquires a DNS server in a mobile communication carrier network about a communication destination address. For this reason, when the number of accesses from the wireless terminal device to the mobile carrier network increases, the traffic volume of the IP packet increases, and the response when communicating using the wireless terminal device may be delayed. In addition, in order to cope with an increase in traffic volume, it may be necessary to add a device such as a DNS server in the mobile communication carrier network.

  However, Patent Document 1 does not disclose a configuration for solving such a problem.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to realize a good communication operation in the wireless terminal device by appropriately controlling traffic between the wireless terminal device and the network. A network connection device, an address information management device, a network system, a network connection method, and a network connection program are provided.

  In order to solve the above-described problem, a network connection device according to an aspect of the present invention acquires inquiry information about a communication destination address from a specific terminal device that is a wireless terminal device permitted to access a specific external network. An inquiry information acquisition unit, a first address information management device that is provided in the specific external network, searches for an address corresponding to the inquiry information, and transmits response information indicating the searched address, and the specific external network The inquiry information acquisition unit acquires the address corresponding to the inquiry information and searches for the address corresponding to the inquiry information and transmits the response information indicating the searched address to the second address information management device. An inquiry information transmission unit for transmitting inquiry information; The response information received from the serial first address information management apparatus and said second address information management apparatus and a response information transmitting unit for transmitting to said specific terminal device.

  With this configuration, for example, the destination of inquiry information from the wireless terminal device can be selected from the first address information management device and the second address information management device in the network connection device. IP traffic can be distributed from the specific external network in which the second address information management device is installed to the general external network in which the second address information management device is installed. Can be reduced. Therefore, by appropriately controlling traffic between the wireless terminal device and the network, a favorable communication operation can be realized in the wireless terminal device.

  Preferably, the network connection device further transmits inquiry destination information for transmitting inquiry destination information indicating that the address information management device which is the transmission destination of the inquiry information is the network connection device, to the specific terminal device. A part.

  With such a configuration, it is possible to prevent inquiry information from the wireless terminal device from being transmitted directly to the address information management device in the general external network or the specific external network through the network connection device. That is, the destination of inquiry information viewed from the wireless terminal device is not the address information management device in the general external network or the specific external network, but a network connection device, and the network connection device is the second address information management device as the inquiry information transmission destination. And it becomes possible to switch the 1st address information management apparatus appropriately.

  Preferably, the inquiry information transmitting unit transmits the inquiry information to the second address information management device when the response information cannot be received even if the inquiry information is transmitted to the first address information management device. Send.

  With this configuration, for example, in the first address information management device in the specific external network, name resolution is performed on the specific external network side according to the communication destination of the wireless terminal device by appropriately setting the domain name and IP address. It is possible to control whether or not. Then, for example, the network connection device controls the IP packet transmitted from the wireless terminal device to be transmitted to the network that is the transmission source of the response information, so that the IP packet is based on the destination of the IP packet from the wireless terminal device. Therefore, it is possible to prevent the processing from becoming complicated and to prevent the processing amount from increasing. In addition, the operator of the specific external network can select an IP packet transmitted and received by the wireless terminal device via the specific external network. That is, by selecting a name resolution destination in a business operator of a specific external network, it is possible to achieve load distribution in the general external network and the specific external network. In addition, by sending inquiry information to a specific external network first, it is possible to speed up the response of a communication service such as content delivery to a wireless terminal device with priority.

  Preferably, the inquiry information acquisition unit further acquires inquiry information of a communication destination address from a general terminal device that is a wireless terminal device or a wired terminal device other than the specific terminal device, and the inquiry information transmission unit further includes The inquiry information acquired from the general terminal device is transmitted to the second address information management device.

  With such a configuration, in the network connection device, it is possible to appropriately switch the transmission destination of the inquiry information from the specific terminal device and the inquiry information from the general terminal device.

  More preferably, the inquiry information transmission unit transmits the inquiry information every time a predetermined time elapses without receiving the response information after transmitting the inquiry information, and the inquiry information acquired from the specific terminal device Is made shorter than the interval for transmitting the inquiry information acquired from the general terminal device.

  In this way, by transmitting the inquiry information from the specific terminal device to both the specific external network and the general external network, the transmission interval of the inquiry information received from the specific terminal device is set to be shorter than that of the general terminal device. Even if the number of destination address information management devices increases, the number of times inquiry information is sent to each address information management device before timeout is the same as when inquiry information from a general terminal device is transmitted only to a general external network. Therefore, the communication can be stabilized. In addition, it is possible to shorten the time required to receive a communication service such as content distribution from a specific external network or a general external network.

  Preferably, the inquiry information transmission unit sequentially transmits the inquiry information to the first address information management device and the second address information management device, and the first address information management device and the second address. If the response information is not received even after a predetermined time has elapsed since the inquiry information is transmitted to one of the information management apparatuses, the inquiry information is transmitted to the other address information management apparatus, and the first address information management If error information indicating that the address corresponding to the inquiry information could not be retrieved from one of the device and the second address information management device is received, the other address information does not wait for the predetermined time to elapse. The inquiry information is transmitted to the management apparatus.

  With such a configuration, it is possible to reduce the time required to send inquiry information to the address information management device on the other network, and to reduce the time required for name resolution.

  Preferably, the inquiry information transmission unit elapses a predetermined time without receiving the response information after transmitting the inquiry information to one of the first address information management device and the second address information management device. Each time the inquiry information is transmitted to the other of the first address information management device and the second address information management device, the inquiry information is sent from the first address information management device or the second address information management device. When the error information indicating that the address corresponding to is not retrieved has been received, the inquiry information is not transmitted to the address information management apparatus that has transmitted the error information.

  With this configuration, it is possible to stop the retransmission of inquiry information to the network that has transmitted the error information, so that the time required for name resolution can be shortened.

  Preferably, the response information transmission unit receives error information indicating that an address corresponding to the inquiry information could not be retrieved from both the first address information management device and the second address information management device. In this case, the error information is transmitted to the specific terminal device.

  With such a configuration, name resolution in the network system can be performed stably.

  Preferably, the inquiry information transmission unit waits for a transition to a state where communication with the second address information management device can be started in a state where communication with the second address information management device cannot be started. When the inquiry information is transmitted to the first address information management device and the state transitions to a state where communication with the second address information management device can be started, the inquiry information to the second address information management device is changed. Start sending.

  With such a configuration, the arrival time of inquiry information to a specific external network can be shortened, and name resolution can be completed early.

  More preferably, the network connection device further includes a storage unit for storing the identification information of the specific terminal device and the identification information of the general terminal device, and the inquiry information acquisition unit is an identification indicated by the inquiry information. By comparing the information with the identification information stored in the storage unit, it is determined whether the transmission source of the inquiry information is the specific terminal device or the general terminal device.

  With such a configuration, inquiry information from a specific terminal device and inquiry information from a general terminal device can be appropriately determined.

  Preferably, the network connection device further receives a radio signal including the inquiry information from the specific terminal device, outputs the received inquiry information to the inquiry information acquisition unit, and from the response information transmission unit A radio interface unit is provided for receiving the response information and transmitting a radio signal including the received response information to the specific terminal device.

  As described above, the configuration in which the home gateway and the radio base station apparatus are integrated allows name resolution to be performed in both the specific external network and the general external network, unlike the gateway dedicated to the radio base station apparatus. As a result, load distribution is appropriately distributed in response to an increase in traffic volume in a specific external network, and the communication connection destination of the wireless terminal device is, for example, a general external network, thereby reducing the communication fee of the user of the wireless terminal device It is also possible to provide such a service.

  More preferably, the wireless interface unit is a femto base station.

  Thus, the network connection apparatus with a high integration effect can be provided by the configuration in which the home gateway and the femto base station are integrated.

  Preferably, the first address information management device searches the address corresponding to the inquiry information received from the network connection device within a range of one or a plurality of addresses stored by itself, and a response indicating the searched address Information is transmitted to the network connection device, and error information is transmitted to the network connection device when the information cannot be retrieved, and the second address information management device corresponds to the inquiry information received from the network connection device. The address is searched in the range of one or a plurality of addresses stored by itself, and when the address cannot be searched, another apparatus is searched for the address corresponding to the inquiry information, and the response information indicating the searched address is the above Send to the network connection device.

  With this configuration, for example, in the first address information management device in the specific external network, the name is set on the specific external network side according to the destination of the IP packet from the wireless terminal device by appropriately setting the domain name and the IP address. It is possible to control whether or not the solution is performed. Then, for example, the network connection device controls the IP packet transmitted from the wireless terminal device to be transmitted to the network that is the transmission source of the response information, so that the IP packet is based on the destination of the IP packet from the wireless terminal device. There is no need to select a destination for. Thereby, it is possible to prevent the processing of the network connection apparatus from becoming complicated, and to prevent the processing amount from increasing. In addition, the operator of the specific external network can select an IP packet transmitted and received by the wireless terminal device via the specific external network. That is, by selecting a name resolution destination in a business operator of a specific external network, it is possible to achieve load distribution in the general external network and the specific external network.

  In order to solve the above problems, an address information management apparatus according to an aspect of the present invention is provided in a specific external network, receives inquiry information of a communication destination address from a network connection apparatus, and corresponds to the received inquiry information. An address information management device for searching for an address and transmitting response information indicating the searched address to the network connection device, wherein the network connection device is a wireless terminal permitted to access the specific external network The inquiry information acquisition unit for acquiring inquiry information of a communication destination address from a specific terminal device, which is a device, the address information management device, and a general external network to which the specific external network is connected, Search for the corresponding address, An inquiry information transmission unit for transmitting the inquiry information acquired by the inquiry information acquisition unit to another address information management device that transmits response information indicating an address, the address information management device, and the other address information A response information transmission unit configured to transmit the response information received from the management device to the specific terminal device.

  With this configuration, for example, in the address information management device in the specific external network, name resolution is performed on the specific external network side according to the destination of the IP packet from the wireless terminal device by appropriately setting the domain name and the IP address. It is possible to control whether or not. Then, for example, the network connection device controls the IP packet transmitted from the wireless terminal device to be transmitted to the network that is the transmission source of the response information, so that the IP packet is based on the destination of the IP packet from the wireless terminal device. There is no need to select a destination for. Thereby, it is possible to prevent the processing of the network connection apparatus from becoming complicated, and to prevent the processing amount from increasing. In addition, the operator of the specific external network can select an IP packet transmitted and received by the wireless terminal device via the specific external network. That is, by selecting a name resolution destination in a business operator of a specific external network, it is possible to achieve load distribution in the general external network and the specific external network.

  In order to solve the above problems, a network system according to an aspect of the present invention includes a network connection device and a first address information management device, and the first address information management device is provided in a specific external network. Receiving the inquiry information of the communication destination address from the network connection device, searching for an address corresponding to the received inquiry information, transmitting response information indicating the searched address to the network connection device, and connecting the network An apparatus includes an inquiry information acquisition unit for acquiring inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access the specific external network, and the first address information management device, And a general external network to which the specific external network is connected The inquiry information acquired by the inquiry information acquisition unit is transmitted to a second address information management device that searches for an address corresponding to the inquiry information and transmits response information indicating the searched address. And a response information transmission unit for transmitting the response information received from the first address information management device and the second address information management device to the specific terminal device.

  With such a configuration, for example, it becomes possible to select a destination of inquiry information from a wireless terminal device in a network connection device, and it becomes possible to distribute IP traffic from a specific external network to a general external network. The amount of IP packet traffic in the external network can be reduced. Therefore, by appropriately controlling traffic between the wireless terminal device and the network, a favorable communication operation can be realized in the wireless terminal device.

  In order to solve the above problem, a network connection method according to an aspect of the present invention includes a step of acquiring inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access a specific external network. A first address information management device that is provided in the specific external network, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address, and a general external to which the specific external network is connected The inquiry information acquired by the inquiry information acquisition unit to at least one of the second address information management devices that is provided in the network, searches for an address corresponding to the inquiry information, and transmits response information indicating the searched address. And transmitting the first address information The response information received from the management apparatus or the second address information management apparatus and transmitting to the specific terminal device.

  With such a configuration, for example, it becomes possible to select a destination of inquiry information from a wireless terminal device in a network connection device, and it becomes possible to distribute IP traffic from a specific external network to a general external network. The amount of IP packet traffic in the external network can be reduced. Therefore, by appropriately controlling traffic between the wireless terminal device and the network, a favorable communication operation can be realized in the wireless terminal device.

  In order to solve the above-described problem, a network connection program according to an aspect of the present invention is a network connection program in a network connection device, and is a wireless terminal device that is permitted to access a specific external network by a computer. A step of acquiring inquiry information of a communication destination address from the terminal device; first address information provided in the specific external network, searching for an address corresponding to the inquiry information, and transmitting response information indicating the searched address At least one of a management device and a second address information management device that is provided in a general external network to which the specific external network is connected, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address To the above inquiry The step of transmitting the inquiry information acquired by the acquisition unit and the step of transmitting the response information received from the first address information management device or the second address information management device to the specific terminal device are executed. Let

  With such a configuration, for example, it becomes possible to select a destination of inquiry information from a wireless terminal device in a network connection device, and it becomes possible to distribute IP traffic from a specific external network to a general external network. The amount of IP packet traffic in the external network can be reduced. Therefore, by appropriately controlling traffic between the wireless terminal device and the network, a favorable communication operation can be realized in the wireless terminal device.

  ADVANTAGE OF THE INVENTION According to this invention, favorable communication operation | movement is realizable in a radio | wireless terminal apparatus by controlling the traffic between a radio | wireless terminal apparatus and a network appropriately.

It is a figure which shows the structure of the network system which concerns on embodiment of this invention. It is a figure which shows the structure of the network connection apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the radio | wireless interface part in the network connection apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the network control part in the network connection apparatus which concerns on embodiment of this invention. It is a figure which shows an example of the sequence of the transmission operation | movement of the DNS query by the network connection apparatus concerning embodiment of this invention. It is a figure which shows an example of the sequence of the transmission operation | movement of the DNS query by the network connection apparatus concerning embodiment of this invention. It is a figure which shows an example of the sequence of the communication operation | movement in the network system which concerns on embodiment of this invention. FIG. 8 is a flowchart mainly defining detailed operation procedures of a WAN side communication unit in the sequence shown in FIG. 7. FIG. It is a figure which shows the sequence of the communication operation | movement in the network system which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Configuration and basic operation]
FIG. 1 is a diagram showing a configuration of a network system according to an embodiment of the present invention.

  Referring to FIG. 1, a network system 401 includes a network connection device 101, a DNS server (second address management device) 301, and a DNS server (first address management device) 302.

  The DNS server 301 is installed in an external network (general external network) 201 that is, for example, an ISP (Internet Service Provider) network. The DNS server 302 is installed in an external network (specific external network) 202 which is a mobile communication carrier network including a PS network that processes packet switching calls, for example. The external networks 201 and 202 are connected to the Internet (not shown), that is, the external networks 201 and 202 are connected via the Internet.

  The network connection device 101 has functions such as IP packet routing and protocol conversion, and connects the internal network 204 in the home and the external networks 201 and 202 to each other via the fixed network 203. The network connection device 101 has, for example, an IPv4 (Internet Protocol version 4) NAPT (Network Address Port Translation) function.

  The fixed network 203 is, for example, an optical communication network. The network connection device 101 communicates with the DNS servers 301 and 302 via the fixed network 203. For example, the network connection apparatus 101 is a VPN such as a PPPoE (Point to Point Protocol over Ethernet (registered trademark)) tunnel or an IPsec (Security Architecture for Internet Protocol) tunnel with an access server (not shown) in the external networks 201 and 202. By forming (Virtual Private Network), IP packets are transmitted and received between the DNS servers 301 and 302 connected to each access server.

  The internal network 204 includes wired terminal devices such as a wireless terminal device 151, a personal computer 152, and a set top box 153.

  The network connection device 101 is connected to the personal computer 152 and the set top box 153 via, for example, a LAN cable, and transmits / receives IP packets to / from each other.

  The network connection apparatus 101 has a function of a femto base station in addition to a normal home gateway function, for example, and transmits / receives a radio signal to / from the wireless terminal apparatus 151. For example, the network connection device 101 and the wireless terminal device 151 perform mobile communication according to LTE (Long Term Evolution) standardized by 3GPP.

  Here, the femto base station is described in 3GPP (Third Generation Partnership Project) SPEC TS22.220 as follows. That is, a femto base station is a customer premises apparatus that connects a wireless terminal device connected via a wireless interface to a mobile communication carrier network using an IP backhaul.

  Such a 3GPP definition may also be applied to the network system according to the embodiment of the present invention.

  Further, the following definitions can be applied together with or separately from the above definitions.

  The macro base station is a radio base station device that is under the management of the operator and can communicate with the radio base station device that has contracted with the operator. In addition, it is considered that the macro base station is basically not turned off.

  A femto base station is a radio base station apparatus that is installed mainly in an individual or corporation building and may be turned off depending on the user's circumstances.

  Further, the femto base station operates in one of open / hybrid / closed access modes. When the femto base station operates in the closed access mode, only registered members (terminals) can be connected. When operating in the closed access mode, the service is provided only to registered members. When operating in the hybrid access mode, the service is provided to both registered members and unregistered members, that is, non-members. Further, when operating in the open access mode, the same operation as the macro base station is performed.

  FIG. 2 is a diagram showing the configuration of the network connection apparatus according to the embodiment of the present invention.

  With reference to FIG. 2, the network connection apparatus 101 includes a network control unit 11, a wireless interface unit 12, and a wired interface unit 13. The network control unit 11 is realized by an arithmetic processing device such as a CPU (Central Processing Unit) or a DSP (Digital Signal Processor).

  The wireless interface unit 12 communicates with the wireless terminal device 151 in the internal network 204. More specifically, the wireless interface unit 12 receives a wireless signal including an IP packet or the like from the wireless terminal device 151, converts the received wireless signal into communication data, and outputs the communication data to the network control unit 11. Further, the wireless interface unit 12 converts communication data including the IP packet received from the network control unit 11 into a wireless signal and transmits the wireless signal to the wireless terminal device 151.

  The wired interface unit 13 communicates with the wired terminal devices 152 and 153 in the internal network 204. More specifically, the wired interface unit 13 receives communication data such as IP packets from the wired terminal devices 152 and 153 and outputs the communication data to the network control unit 11. The wired interface unit 13 transmits communication data such as an IP packet received from the network control unit 11 to the wired terminal devices 152 and 153.

  The network control unit 11 performs relay processing of communication data among the wireless interface unit 12, the wired interface unit 13, and the fixed network 203 by performing various communication protocol processes. That is, the network control unit 11 outputs the communication data received from the wireless interface unit 12 to the fixed network 203 or the wired interface unit 13. Further, the network control unit 11 outputs the communication data received from the wired interface unit 13 to the fixed network 203 or the wireless interface unit 12. Further, the network control unit 11 receives communication data such as an IP packet from the fixed network 203 and outputs it to the wireless interface unit 12 or the wired interface unit 13.

  FIG. 3 is a diagram showing a configuration of a wireless interface unit in the network connection apparatus according to the embodiment of the present invention.

  Referring to FIG. 3, the wireless interface unit 12 has a function as, for example, a femto base station, and includes an antenna 91, a circulator 92, a wireless reception unit 93, a wireless transmission unit 94, and a signal processing unit 95. With. The signal processing unit 95 includes a reception signal processing unit 96 and a transmission signal processing unit 97. The signal processing unit 95 is realized by an arithmetic processing device such as a CPU or a DSP.

  The circulator 92 outputs the radio signal from the radio terminal device 151 received by the antenna 91 to the radio reception unit 93 and outputs the radio signal received from the radio transmission unit 94 to the antenna 91.

  The radio reception unit 93 converts the radio signal received from the circulator 92 into a baseband signal or IF (Intermediate Frequency) signal, converts the frequency-converted signal into a digital signal, and outputs the digital signal to the reception signal processing unit 96.

  The received signal processing unit 96 performs signal processing such as despreading in the CDMA (Code Division Multiple Access) method on the digital signal received from the wireless receiving unit 93, and part or all of the digital signal after this signal processing is performed. The data is converted into a predetermined frame format and output to the network control unit 11.

  The transmission signal processing unit 97 performs IFFT (Inverse Fast Fourier Transform) in the OFDM (Orthogonal Frequency Division Multiplex) method on communication data obtained by converting communication data received from the network control unit 11 into a predetermined frame format or communication data generated by itself. ) And the like, and the digital signal after this signal processing is output to the wireless transmission unit 94.

  The radio transmission unit 94 converts the digital signal received from the transmission signal processing unit 97 into an analog signal, converts the frequency of the converted analog signal into a radio signal, and outputs the radio signal to the circulator 92.

  FIG. 4 is a diagram showing a configuration of a network control unit in the network connection apparatus according to the embodiment of the present invention.

  Referring to FIG. 4, network control unit 11 includes an inquiry information acquisition unit 21, an inquiry information transmission unit 22, a response information transmission unit 23, an inquiry destination information transmission unit 24, and a storage unit 25.

  The storage unit 25 includes identification information of a specific terminal device that is a terminal device permitted to transmit a DNS query to the DNS server 302 in the PS network 202, that is, a terminal device permitted to access the PS network 202, and a specific terminal. Identification information of a general terminal device that is a terminal device other than the device is stored.

  Here, the network connection apparatus 101 acquires the identification information of the wireless terminal apparatus 151 that is the specific terminal apparatus in, for example, the establishment process of the RRC (Radio Resource Control) connection with the wireless terminal apparatus 151, and thus the wireless terminal It is possible to distinguish from the identification information of other general terminal devices that establish a communication connection with a communication protocol different from that of the device 151.

  The inquiry information acquisition unit 21 acquires the inquiry information of the communication destination address from the wireless terminal device 151, that is, the DNS query via the wireless interface unit 12. That is, the wireless interface unit 12 illustrated in FIG. 2 receives a wireless signal including a DNS query from the wireless terminal device 151 and outputs the DNS query to the inquiry information acquisition unit 21.

  The inquiry information acquisition unit 21 acquires a DNS query from the personal computer 152 and the set top box 153 via the wired interface unit 13. That is, the wired interface unit 13 illustrated in FIG. 2 receives communication data including a DNS query from the personal computer 152 and the set top box 153 and outputs the DNS query to the inquiry information acquisition unit 21.

  The inquiry information transmission unit 22 transmits the DNS query from the wireless terminal device 151 acquired by the inquiry information acquisition unit 21 to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202. Further, the inquiry information transmission unit 22 transmits the DNS query from the personal computer 152 and the set top box 153 acquired by the inquiry information acquisition unit 21 to the DNS server 301 in the ISP network 201.

  Here, the DNS server 302 in the PS network 202 searches the address corresponding to the DNS query within a range of one or a plurality of addresses stored by itself, transmits a DNS response indicating the searched address, and has not been able to search. In this case, error information is transmitted.

  In addition, the DNS server 301 in the ISP network 201 searches for an address corresponding to the DNS query within a range of one or a plurality of addresses stored by itself, and if the DNS server 301 fails to search, it responds to the DNS query to another DNS server. The address to be searched is searched, and a DNS response indicating the searched address is transmitted.

  The response information transmission unit 23 sends the DNS responses received from the DNS server 302 in the PS network 202 and the DNS server 301 in the ISP network 201 to the wireless terminal device 151, personal computer 152, or set-top box 153 that is the transmission source of the DNS query. Send.

  That is, the wireless interface unit 12 illustrated in FIG. 2 receives a DNS response from the response information transmission unit 23 and transmits a wireless signal including the DNS response to the wireless terminal device 151. 2 receives the DNS response from the response information transmission unit 23, and transmits communication data including the DNS response to the personal computer 152 and the set top box 153.

  The inquiry destination information sending unit 24 sends inquiry destination information indicating that the DNS server to which the DNS query is sent is the network connection device 101, that is, if the inquiry destination of the communication destination address is the network connection device 101, the wireless terminal device 151 Inquiry information for recognizing is transmitted to the wireless terminal device 151. That is, the wireless interface unit 12 illustrated in FIG. 2 receives the inquiry destination information from the inquiry destination information transmission unit 24 and transmits a wireless signal including the inquiry destination information to the wireless terminal device 151.

[Operation]
Next, the operation when the network connection apparatus according to the embodiment of the present invention performs name resolution will be described.

  Here, when the DNS server 302 in the PS network 202 is duplexed with the primary DNS server 302 and the secondary DNS server 302, and the DNS server 301 in the ISP network 201 is duplexed with the primary DNS server 301 and the secondary DNS server 301 Will be described. A case will be described in which the wireless terminal device 151 is a specific terminal device and the personal computer 152 and the set top box 153 are general terminal devices.

  In the sequence and flowchart shown below, the network connection apparatus 101 reads a program including each step from, for example, the storage unit 25 illustrated in FIG. 4 and executes each step. This program can be installed externally. The installed program is distributed in a state stored in a recording medium, for example.

  FIG. 5 is a diagram showing an exemplary sequence of a DNS query transmission operation performed by the network connection apparatus according to the embodiment of the present invention. FIG. 5 shows a case where the network connection apparatus 101 receives a DNS query from the wireless terminal apparatus 151 which is a specific terminal apparatus.

  Referring to FIG. 5, network connection apparatus 101 transmits a DNS query from wireless terminal apparatus 151 to both PS network 202 and ISP network 201.

  That is, the inquiry information transmitting unit 22 sequentially transmits the DNS query to the DNS server 302 in the PS network 202 and the DNS server 301 in the ISP network 201, and to one of the DNS server 302 in the PS network 202 and the DNS server 301 in the ISP network 201. When a DNS response is not received even if a DNS query is transmitted, a DNS query is transmitted to the other DNS server.

  More specifically, the inquiry information transmission unit 22 alternately transmits a DNS query to the DNS server 302 in the PS network 202 and the DNS server 301 in the ISP network 201 without receiving a DNS response after transmitting the DNS query. A DNS query is transmitted to the DNS server 302 or the DNS server 301 every time a predetermined time elapses. In addition, the inquiry information transmission unit 22 transmits a DNS query to the DNS server 302 in the PS network 202 before the DNS server 301 in the ISP network 201.

  In the example illustrated in FIG. 5, when the network connection apparatus 101 receives the DNS query from the specific terminal apparatus, the network connection apparatus 101 first transmits the DNS query to the primary DNS server 302 in the PS network 202 and then the secondary DNS server in the PS network 202. A DNS query is transmitted to 302, then a DNS query is transmitted to the primary DNS server 301 in the ISP network 201, and then a DNS query is transmitted to the secondary DNS server 301 in the ISP network 201.

  If the network connection apparatus 101 performs the above transmission operation twice, that is, if response information cannot be received even if the DNS query is transmitted twice to each DNS server, the DNS query is first sent to the primary DNS server 302. Time TOUT elapses from transmission to time out.

  Here, the network connection apparatus 101 sets the source IP address of the DNS query to the global address given from the ISP network 201 when sending to the ISP network 201, and gives it from the PS network 202 when sending to the PS network 202. Set to the specified global address.

  FIG. 6 is a diagram showing an exemplary sequence of a DNS query transmission operation by the network connection apparatus according to the embodiment of the present invention. FIG. 6 shows a case where the network connection apparatus 101 receives DNS queries from the personal computer 152 and the set top box 153 which are general terminal apparatuses.

  Referring to FIG. 6, network connection apparatus 101 transmits a DNS query from personal computer 152 or set top box 153 to ISP network 201.

  More specifically, upon receiving a DNS query from the personal computer 152 or the set top box 153, the network connection apparatus 101 first transmits a DNS query to the primary DNS server 301 in the ISP network 201, and then in the ISP network 201. A DNS query is transmitted to the secondary DNS server 301.

  If the network connection apparatus 101 cannot receive response information even if it sends a DNS query three times to the primary DNS server 301 and twice to the secondary DNS server 301, it first sends the DNS query to the primary DNS server 301. Then, the time TOUT elapses and a timeout occurs.

  As can be seen from FIG. 5 and FIG. 6, the inquiry information transmitting unit 22 transmits a DNS query every time a predetermined time elapses without receiving a DNS response after transmitting a DNS query. And the inquiry information transmission part 22 makes the space | interval which transmits the DNS query acquired from the specific terminal device shorter than the space | interval which transmits the DNS query acquired from the general terminal device.

  Specifically, the DNS query transmission interval T1 when the DNS query from the wireless terminal device 151 that is the specific terminal device is transmitted to both the PS network 202 and the ISP network 201 is the personal computer 152 that is the general terminal device or The DNS query from the set top box 153 is set to be shorter than the DNS query transmission interval T2 in the case where the DNS query is transmitted only to the ISP network 201.

  In this way, by transmitting the DNS query from the specific terminal device to both the PS network 202 and the ISP network 201 with a configuration in which the transmission interval of the DNS query received from the specific terminal device is set shorter than that of the general terminal device. Even if the number of destination DNS servers increases, the number of times that a DNS query is transmitted to each server before a timeout may be made the same as when only a DNS query from a general terminal device is transmitted to the ISP network 201. Therefore, communication can be stabilized. In addition, it is possible to shorten the time until receiving a communication service such as content distribution from a server in the PS network 202 or the ISP network 201.

  FIG. 7 is a diagram showing an exemplary sequence of communication operations in the network system according to the embodiment of the present invention. 7, the LAN side communication unit corresponds to the inquiry information acquisition unit 21, inquiry information transmission unit 22, and response information transmission unit 23 shown in FIG. 4, and the WAN side communication unit corresponds to the inquiry information transmission unit 22 and response information transmission unit 23. The terminal management unit corresponds to the inquiry information acquisition unit 21. Various information such as access information and a destination list described below is stored in the storage unit 25 shown in FIG.

  Referring to FIG. 7, first, the wireless terminal device 151 transmits a DNS query to the network connection device 101 (step S1).

  Next, the LAN side communication unit in the network connection device 101 receives the DNS query from the wireless terminal device 151, and transmits a terminal information request including information on the DNS query to the terminal management unit (step S2).

  Next, the terminal management unit compares the identification information indicated by the DNS query with the identification information stored in the storage unit 25 illustrated in FIG. 4, thereby determining whether the transmission source of the DNS query is a specific terminal device. Is determined (step S3).

  Here, the terminal management unit stores in the storage unit 25 the IP address of the DNS server 302 in the PS network acquired from the mobile communication carrier network 202. The terminal management unit stores the transmission source IP address for the PS network acquired from the mobile communication carrier network 202, that is, the IP address for accessing the PS network 202, in the storage unit 25.

  Next, when the terminal management unit determines that the DNS query from the wireless terminal device 151 is a DNS query from the specific terminal device, two types of IP addresses for the PS network corresponding to the wireless terminal device 151, that is, the PS network A response indicating the IP address of the DNS server 302 in 202 and the IP address for accessing the PS network 202 is notified to the LAN side communication unit (step S4).

  Next, the LAN side communication unit creates access information indicating the two types of IP addresses for the PS network notified from the terminal management unit and the IP address of the DNS server 301 in the ISP network 201 (step S5). The IP address of the DNS server 301 is stored in the storage unit 25.

  Next, the LAN side communication unit notifies the created access information and the received DNS query information to the WAN side communication unit (step S6).

  Next, the WAN-side communication unit creates a destination list that is a list of DNS servers that are DNS query transmission destinations. In this destination list, for example, the IP address of each DNS server is listed in the form of an array. The IP address of the primary DNS server 302 in the PS network 202 is stored in the element dns [0], and the element dns [1]. The IP address of the secondary DNS server 302 in the PS network 202 is stored, the IP address of the primary DNS server 301 in the ISP network 201 is stored in the element dns [2], and the secondary DNS server 301 in the ISP network 201 is stored in the element dns [3]. Are stored (step S7).

  Next, the WAN side communication unit transmits the DNS query notified from the LAN side communication unit in accordance with the destination list. That is, the WAN side communication unit transmits a DNS query to each DNS server in the order of the elements dns [0], dns [1], dns [2], and dns [3] in the destination list. In this case, the WAN-side communication unit first transmits a DNS query to the DNS server 302 in the PS network 202 corresponding to the elements dns [0] and dns [1] (step S8).

  Next, the DNS server 302 in the PS network 202 searches the IP address corresponding to the domain name indicated by the DNS query received from the WAN side communication unit with reference to the correspondence table between the domain name and the IP address stored therein. (Step S9).

  Next, when the DNS server 302 in the PS network 202 cannot search for the IP address corresponding to the DNS query, the DNS server 302 transmits error information indicating that the search has failed to the network connection apparatus 101 (step S10). .

  Next, the WAN side communication unit in the network connection apparatus 101 receives error information from the DNS server 302 in the PS network 202 and updates the destination list. That is, the WAN side communication unit deletes the primary DNS server 302 and the secondary DNS server 302 in the PS network 202 from the destination list. Specifically, null data is overwritten on the elements dns [0] and dns [1] of the destination list (step S11). When the referenced destination list element is null data, the WAN side communication unit refers to the next element as the DNS query transmission destination.

  Also, the WAN side communication unit receives error information from the DNS server 302 in the PS network 202, and immediately transmits a DNS query to the next destination. That is, the WAN communication unit transmits a DNS query to the DNS server 301 in the ISP network 201 corresponding to the elements dns [2] and dns [3] without leaving the transmission interval T1 (steps S12 and S13).

  Next, the DNS server 301 in the ISP network 201 searches the IP address corresponding to the domain name indicated by the DNS query received from the WAN side communication unit with reference to the correspondence table between the domain name and the IP address stored by itself. (Step S14).

  Next, the DNS server 301 in the ISP network 201 transmits a DNS response indicating the IP address corresponding to the DNS query to the network connection apparatus 101 (step S15).

  Next, the WAN side communication unit in the network connection apparatus 101 receives the DNS response from the DNS server 301 in the ISP network 201, notifies the LAN side communication unit of the DNS response (step S16), and deletes the destination list. (Step S17).

  Next, when a DNS response is notified from the WAN side communication unit, the LAN side communication unit transmits the DNS response to the wireless terminal device 151 (step S18) and deletes the access information (step S19).

  FIG. 8 is a flowchart mainly defining detailed operation procedures of the WAN side communication unit in the sequence shown in FIG.

  Referring to FIG. 8, first, network connection apparatus 101 receives a response from the DNS server in a state where a DNS query is transmitted to a certain DNS server (step S21).

  Next, when the response from the DNS server is not the error information but a DNS response (NO in step S22), the network connection apparatus 101 transmits a DNS response to the wireless terminal apparatus 151 (step S27).

  On the other hand, when the response from the DNS server is error information (YES in step S22), the network connection apparatus 101 deletes the DNS server in the network that transmitted the error information from the destination list (step S23).

  Next, when a DNS server remains in the destination list (YES in step S24), the network connection apparatus 101 transmits a DNS query to the next destination DNS server (step S25).

  On the other hand, if no DNS server remains in the destination list (NO in step S24), the network connection apparatus 101 transmits error information to the wireless terminal apparatus 151 (step S26).

  As described with reference to FIGS. 7 and 8, the network connection apparatus 101 transmits the DNS query from the wireless terminal apparatus 151 to both the PS network 202 and the ISP network 201. For this reason, even if error information is received from the DNS server of one network, name resolution may be successful in the DNS server of the other network.

  Therefore, in the network connection apparatus 101, when the response information transmission unit 23 receives error information indicating that the address corresponding to the DNS query could not be retrieved from both the DNS server 302 and the DNS server 301, the error information is displayed. Transmit to the wireless terminal device 151.

  That is, when the network connection apparatus 101 receives error information, the network connection apparatus 101 determines whether error information has been received from only one network or whether error information has been received from both the PS network 202 and the ISP network 201.

  If the network connection apparatus 101 receives error information only from one network, the error information is ignored. Then, the network connection apparatus 101 transmits error information to the wireless terminal apparatus 151 for the first time when the error information is received from both networks.

  With such a configuration, name resolution in the network system can be performed stably.

  In this way, the network connection apparatus 101 ignores error information from one network. However, if it is simply ignored, it takes time to send a DNS query to the DNS server of the other network, resulting in a longer time for name resolution.

  Therefore, in the network connection apparatus 101, the inquiry information transmission unit 22 transmits the DNS query to one of the DNS server 302 and the DNS server 301, and if the DNS response is not received even after a predetermined time has elapsed, Send a DNS query to the server. When the inquiry information transmission unit 22 receives error information indicating that the address corresponding to the DNS query could not be retrieved from one of the DNS server 302 and the DNS server 301, the inquiry information transmission unit 22 does not wait for the predetermined time to elapse. Send a DNS query to the other DNS server.

  That is, when the network connection apparatus 101 receives DNS error information from one network, it immediately transmits a DNS query to the other network.

  With such a configuration, it is possible to reduce the time required to send a DNS query to the DNS server of the other network, and to reduce the time required for name resolution.

  In many cases, it is meaningless to retransmit a DNS query to a network that has already transmitted error information.

  Therefore, in the network connection apparatus 101, the inquiry information transmission unit 22 has received error information indicating that the address corresponding to the DNS query could not be retrieved from the DNS server 302 in the PS network 202 or the DNS server 301 in the ISP network 201. In this case, the DNS query is not transmitted to the DNS server that transmitted the error information.

  Specifically, when receiving the error information, the network connection apparatus 101 deletes the DNS server in the network that has transmitted the error information from the destination list.

  With such a configuration, retransmission of a DNS query to a network that has transmitted error information can be stopped, so that the time required for name resolution can be shortened.

  In addition, the network connection apparatus 101 creates a destination list in which the IP addresses of DNS servers in both the PS network 202 and the ISP network 201 are arranged in the order of transmission.

  With such a configuration, the next transmission destination is searched while referring to the list indicating the IP address of the DNS server in the PS network 202 and the list indicating the IP address of the DNS server in the ISP network 201, and a DNS query is transmitted. Compared with the configuration, the transmission process can be simplified and the DNS query can be transmitted early.

  FIG. 9 is a diagram showing a communication operation sequence in the network system according to the embodiment of the present invention. In FIG. 9, a PPP (Point to Point Protocol) connection management unit corresponds to the inquiry information transmission unit 22 shown in FIG.

  Referring to FIG. 9, the operations in steps S31 to S34 are the same as the operations in steps S1 to S4 in the sequence shown in FIG.

  Next, the LAN side communication unit creates access information indicating two types of IP addresses for the PS network notified from the terminal management unit (step S35).

  Next, the LAN side communication unit sends a PPP connection status request for inquiring whether or not a process for establishing a communication path with the DNS server 301 in the ISP network 201, for example, a PPP connection process is completed, to the PPP connection management unit. Notification is made (step S36).

  Next, when the PPP connection processing is not completed, the PPP connection management unit notifies the LAN side communication unit of a response indicating that the PPP connection with the DNS server 301 in the ISP network 201 is in a disconnected state. (Step S37).

  Next, when a response indicating that the LAN side communication unit is in the disconnected state is notified from the PPP connection management unit, the LAN side communication unit sends a PPP connection request for causing the PPP connection management unit to execute the PPP connection processing. Notification is made (step S38).

  In parallel with this, the LAN side communication unit notifies the created access information and the received DNS query information to the WAN side communication unit (step S39).

  Next, the WAN-side communication unit creates a destination list that is a list of DNS servers that are DNS query transmission destinations. More specifically, the WAN side communication unit registers only the DNS server 302 in the PS network 202 in the destination list. That is, in this destination list, in the form of an array having two elements, the IP address of the primary DNS server 302 in the PS network 202 is stored in the element dns [0], and the secondary address in the PS network 202 is stored in the element dns [1]. The IP address of the DNS server 302 is stored (step S40).

  Next, the WAN side communication unit transmits the DNS query notified from the LAN side communication unit in accordance with the destination list. That is, the WAN side communication unit transmits a DNS query to each DNS server in the order of the elements dns [0] and dns [1] in the destination list until a DNS response is received from the DNS server (step S41).

  In parallel with the transmission of the DNS query by the WAN side communication unit, the LAN side communication unit periodically notifies the PPP connection state request to the PPP connection management unit, and periodically determines whether or not the PPP connection processing is completed. An inquiry is made (step S42).

  Next, when the PPP connection processing is completed, the PPP connection management unit notifies the LAN side communication unit of a response indicating that the PPP connection is established with the DNS server 301 in the ISP network 201 (step S1). S43).

  Next, the LAN side communication unit updates the access information when a response indicating that the PPP connection is established is notified from the PPP connection management unit. That is, the LAN side communication unit creates access information indicating the two types of IP addresses for the PS network notified from the terminal management unit and the IP address of the DNS server 301 in the ISP network 201 (step S44).

  Next, the LAN side communication unit notifies the updated access information and the received DNS query information to the WAN side communication unit (step S45).

  Next, the WAN side communication unit updates the destination list. That is, the WAN side communication unit adds the DNS server in the ISP network 201 to the destination list. Specifically, in the updated destination list, for example, the IP address of each DNS server is listed in the form of an array, and the IP address of the primary DNS server 302 in the PS network 202 is stored in the element dns [0]. , The IP address of the secondary DNS server 302 in the PS network 202 is stored in the element dns [1], the IP address of the primary DNS server 301 in the ISP network 201 is stored in the element dns [2], and the ISP is stored in the element dns [3]. The IP address of the secondary DNS server 301 in the network 201 is stored (step S46).

  Next, the WAN side communication unit transmits the DNS query notified from the LAN side communication unit in accordance with the destination list. In this case, the WAN-side communication unit first transmits a DNS query to the DNS server 301 in the ISP network 201 corresponding to the newly added elements dns [2] and dns [3] (step S47).

  Next, the DNS server 301 in the ISP network 201 searches the IP address corresponding to the domain name indicated by the DNS query received from the WAN side communication unit with reference to the correspondence table between the domain name and the IP address stored by itself. If the IP address cannot be retrieved, the DNS server is caused to retrieve the IP address (step S48).

  Next, the DNS server 301 in the ISP network 201 transmits a DNS response indicating the IP address corresponding to the DNS query to the network connection apparatus 101 (step S49).

  Next, the WAN side communication unit in the network connection apparatus 101 receives the DNS response from the DNS server 301 in the ISP network 201, notifies the LAN response to the LAN side communication unit (step S50), and deletes the destination list. (Step S51).

  Next, when the DNS response is notified from the WAN side communication unit, the LAN side communication unit transmits the DNS response to the wireless terminal device 151 (step S52) and deletes the access information (step S53).

  Here, when the network connection apparatus 101 receives a DNS query from the wireless terminal apparatus 151, when PPP is not established with the ISP network 201, that is, communication with the DNS server 301 in the ISP network 201. In the case where the preparation for starting the connection is not completed, a DNS query is not transmitted until the PPP connection is established or the PPP connection times out.

  However, even if the PPP connection with the ISP network 201 is not established when the DNS query from the wireless terminal device 151 is received, it is possible to transmit the DNS query to the DNS server 302 in the PS network 202. is there. When waiting without establishing a DNS query until the PPP connection is established, at least this waiting time takes time to complete the name resolution.

  Therefore, as described with reference to FIG. 9, in the network connection apparatus 101, the inquiry information transmission unit 22 enters a state where communication with the DNS server 301 can be started in a state where communication with the DNS server 301 in the ISP network 201 cannot be started. A DNS query is transmitted to the DNS server 302 in the PS network 202 without waiting for the transition. And the inquiry information transmission part 22 will start transmission of the DNS query to the DNS server 301, if it changes to the state which can start communication with the DNS server 301. FIG.

  That is, the network connection apparatus 101 transmits a DNS query preceding only the PS network 202 in parallel with performing the PPP connection operation, and when the PPP connection with the ISP network 201 is established, the network connection apparatus 101 transmits to the ISP network 201. DNS query transmission starts.

  With such a configuration, it is possible to shorten the DNS query arrival time to the PS network 202 and complete name resolution early.

  By the way, when transmitting an IP packet, a wireless terminal device such as a mobile phone usually inquires of a DNS server in a mobile communication carrier network about a communication destination address. For this reason, when the number of accesses from the wireless terminal device to the mobile carrier network increases, the traffic volume of the IP packet increases, the response when communicating using the wireless terminal device becomes slow, and the traffic volume In order to cope with this increase, there is a problem that it may be necessary to add a device such as a DNS server in the mobile communication carrier network.

  On the other hand, in the network connection device according to the embodiment of the present invention, the inquiry information acquisition unit 21 acquires a DNS query from the wireless terminal device 151. The inquiry information transmission unit 22 transmits the DNS query to the DNS server 302 and the DNS server 301. The response information transmission unit 23 transmits the DNS response received from the DNS server 302 and the DNS server 301 to the wireless terminal device 151.

  With such a configuration, for example, it is possible to select the transmission destination of the DNS query from the wireless terminal device 151 in the network connection device 101, and it is possible to distribute IP traffic from the PS network to the ISP network. It is possible to reduce the amount of IP packet traffic in the communication carrier network.

  Therefore, in the network connection device according to the embodiment of the present invention, it is possible to realize a good communication operation in the wireless terminal device by appropriately controlling traffic between the wireless terminal device and the network.

  In the network connection apparatus according to the embodiment of the present invention, the inquiry destination information transmission unit 24 transmits inquiry destination information indicating that the address information management apparatus that is the transmission destination of the DNS query is the network connection apparatus 101. Transmit to device 151.

  Specifically, in the network connection device according to the embodiment of the present invention, the DNS server address given to the wireless terminal device 151 is the private address of the network connection device 101, that is, the LAN side address. As a result, the network connection apparatus 101 can distribute the transmission destination of the DNS query from the wireless terminal apparatus 151.

  With such a configuration, it is possible to prevent the DNS query from the wireless terminal device 151 from being transmitted directly to the DNS server in the ISP network 201 or the PS network 202 through the network connection device 101. That is, the DNS query transmission destination viewed from the wireless terminal apparatus 151 is not the DNS server in the ISP network 201 or the PS network 202 but the network connection apparatus 101, and the network connection apparatus 101 is the DNS server in the ISP network 201 as the DNS query transmission destination. The DNS server 302 in the 301 and the PS network 202 can be switched appropriately.

  In the network connection device according to the embodiment of the present invention, the inquiry information transmission unit 22 transmits the DNS query to the DNS server 301 when the DNS query cannot be received even if the DNS query is transmitted to the DNS server 302. To do. That is, the inquiry information transmission unit 22 transmits a DNS query to the DNS server 302 in the PS network 202 prior to the DNS server 301 in the ISP network 201.

  That is, the network connection apparatus 101 first makes an inquiry to the DNS server 302 of the PS network 202, and makes an inquiry to the DNS server 301 of the ISP network 201 when name resolution fails.

  With such a configuration, whether or not name resolution is performed on the PS network 202 side according to the communication destination of the wireless terminal device 151 by appropriately setting the domain name and IP address in the DNS server 302 in the PS network 202, for example. Can be controlled.

  Here, as a method of performing load distribution in the PS network 202 and the ISP network 201, for example, the network connection device uses either the PS network 202 or the ISP network 201 based on the destination of the IP packet from the wireless terminal device 151. A configuration in which the transmission destination of the IP packet is selected can be considered.

  However, with such a configuration, the processing of the network connection device becomes complicated and the processing amount increases.

  On the other hand, in the network connection apparatus according to the embodiment of the present invention, the inquiry information transmission unit 22 transmits a DNS query to the DNS server 302 in the PS network 202 before the DNS server 301 in the ISP network 201. In such a configuration, for example, the network connection apparatus 101 controls the IP packet transmitted by the wireless terminal apparatus 151 to be transmitted to the network that is the source of the DNS response, whereby the IP packet from the wireless terminal apparatus 151 is transmitted. There is no need to select the destination of the IP packet based on the destination.

  Therefore, in the network connection device according to the embodiment of the present invention, it is possible to prevent the processing from becoming complicated and to prevent the processing amount from increasing. In addition, the mobile communication carrier can select an IP packet that is transmitted and received by the wireless terminal device 151 via the PS network 202. That is, by selecting a name resolution destination in the mobile communication carrier, it is possible to distribute the load in the ISP network and the PS network. In addition, by transmitting the DNS query to the PS network 202 first, it is possible to speed up the response of a communication service such as content distribution to a mobile phone with priority.

  The inquiry information acquisition unit 21 acquires a DNS query from the specific terminal device and a DNS query from the general terminal device. Then, the inquiry information transmission unit 22 transmits the DNS query acquired from the specific terminal device to the DNS server 302 and the DNS server 301, and transmits the DNS query acquired from the general terminal device to the DNS server 301.

  With such a configuration, it is possible to appropriately switch the transmission destination of the DNS query from the specific terminal device and the DNS query from the general terminal device in the network connection device.

  In the network connection device according to the embodiment of the present invention, the storage unit 25 includes identification information of a specific terminal device that is a terminal device that is permitted to transmit a DNS query to the DNS server 302 in the PS network 202, and Identification information of a general terminal device that is a terminal device other than the specific terminal device is stored. Then, the terminal management unit determines whether the transmission source of the DNS query is a specific terminal device or a general terminal device by comparing the identification information indicated by the DNS query with the identification information stored in the storage unit 25. To do.

  With such a configuration, it is possible to appropriately determine a DNS query from a specific terminal device and a DNS query from a general terminal device.

  In the network connection device according to the embodiment of the present invention, the wireless interface unit 12 receives a wireless signal including a DNS query from the wireless terminal device 151, and outputs the received DNS query to the inquiry information acquisition unit 21. . Further, the wireless interface unit 12 receives a DNS response from the response information transmission unit 23 and transmits a wireless signal including the received DNS response to the wireless terminal device 151.

  As described above, by integrating the home gateway and the radio base station apparatus such as the femto base station, name resolution can be performed in both the PS network 202 and the ISP network 201 unlike the gateway dedicated to the femto base station. Thereby, load distribution is appropriately performed with respect to an increase in traffic volume in the mobile communication carrier network, and the communication connection destination of the wireless terminal device 151 is, for example, the ISP network 201, so that the user of the wireless terminal device 151 It is also possible to provide services that reduce communication charges.

  In the network system according to the embodiment of the present invention, the DNS server 302 in the PS network 202 receives the DNS query from the network connection apparatus 101, and stores one or a plurality of addresses stored by itself. The DNS response indicating the searched address is transmitted to the network connection apparatus 101. If the search cannot be performed, error information is transmitted to the network connection apparatus 101.

  With such a configuration, for example, in the DNS server 302 in the PS network 202, name resolution is performed on the PS network 202 side according to the destination of the IP packet from the wireless terminal device 151 by appropriately setting the domain name and the IP address. It is possible to control whether or not. Then, for example, the network connection apparatus 101 controls the IP packet transmitted by the wireless terminal apparatus 151 to be transmitted to the network that is the source of the DNS response, so that the IP address from the wireless terminal apparatus 151 is based on the destination of the IP packet. There is no need to select the destination of the IP packet.

  Thereby, it is possible to prevent the processing of the network connection apparatus from becoming complicated, and to prevent the processing amount from increasing. In addition, the mobile communication carrier can select an IP packet that is transmitted and received by the wireless terminal device 151 via the PS network 202. That is, by selecting a name resolution destination in the mobile communication carrier, it is possible to distribute the load in the ISP network and the PS network.

[Modification]
In the network connection device according to the embodiment of the present invention, the inquiry information transmission unit 22 sequentially transmits the DNS query to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202, and transmits the DNS query. The DNS query is transmitted to the DNS server of another network when a DNS response is not received even after a predetermined time has elapsed. However, the present invention is not limited to this. For example, the inquiry information transmission unit 22 may multicast the DNS query to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202. Alternatively, the DNS query may be sequentially transmitted to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202 with a predetermined time difference without waiting for the elapse of the predetermined time.

  Further, in the network connection device according to the embodiment of the present invention, the inquiry information transmitting unit 22 is configured to repeatedly transmit the DNS query to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202 alternately and repeatedly. However, the present invention is not limited to this. The inquiry information transmission unit 22 may be configured to transmit a DNS query once to the DNS server 301 in the ISP network 201 and the DNS server 302 in the PS network 202 before timeout.

  The network connection apparatus according to the embodiment of the present invention has a function as a femto base station, directly receives a DNS query from the wireless terminal apparatus 151 by a wireless signal, and transmits a DNS response to the wireless terminal apparatus 151. Although the direct transmission is assumed to be configured, the present invention is not limited to this. The femto base station may be provided separately from the network connection apparatus 101, and the network connection apparatus 101 may receive a DNS query and transmit a DNS response via the femto base station.

  In the network system according to the embodiment of the present invention, the DNS server 301 is configured to be installed in the ISP network 201. However, the present invention is not limited to this. The DNS server 301 may be installed in the fixed network 203 instead of the ISP network 201.

  Further, in the network system according to the embodiment of the present invention, the DNS server of each network is configured to be duplicated as primary and secondary, but the present invention is not limited to this. Only one DNS server as a communication partner of the network connection apparatus 101 may be provided in each network, or three or more DNS servers may be provided.

  Further, when there are a plurality of PS networks, the DNS server in each PS network may be handled as the first address information management device in the present invention, and the present invention is also applied to such a case. Similarly, when there are a plurality of ISP networks, the DNS server in each ISP network may be handled as the second address information management apparatus in the present invention, and the present invention is also applied to such a case.

  In the network system according to the embodiment of the present invention, the specific terminal device is the wireless terminal device 151 and the general terminal device is the wired terminal device of the personal computer 152 and the set-top box 153. However, the present invention is not limited to this. Not what you want. For example, a personal computer 152 that communicates with the network connection apparatus 101 by inserting a wireless LAN card and transmitting and receiving wireless signals may correspond to a general terminal apparatus. In addition, the wireless terminal device 151 of a user who contracts with a mobile communication carrier different from the mobile communication carrier that manages the external network 202 may correspond to a general terminal device.

  In the network connection device according to the embodiment of the present invention, the inquiry information transmission unit 22 transmits a DNS query from the wireless terminal device 151 to the DNS server 302 and the DNS server 301. This does not mean that the inquiry information transmitting unit 22 transmits the DNS query to both the DNS server 302 and the DNS server 301 in all cases, but means that such a function is provided. To do.

  In the network connection device according to the embodiment of the present invention, the response information transmission unit 23 transmits the DNS response received from the DNS server 302 and the DNS server 301 to the wireless terminal device 151. This does not mean that the response information transmission unit 23 transmits the DNS response received from both the DNS server 302 and the DNS server 301 to the wireless terminal device 151 in all cases, and has such a function. Means that

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 11 Network control part 12 Wireless interface part 13 Wired interface part 21 Inquiry information acquisition part 22 Inquiry information transmission part 23 Response information transmission part 24 Inquiry destination information transmission part 25 Storage part 91 Antenna 92 Circulator 93 Wireless reception part 94 Wireless transmission part 95 Signal Processing unit 96 Reception signal processing unit 97 Transmission signal processing unit 101 Network connection device 151 Wireless terminal device 152 Personal computer 153 Set-top box 201 External network, ISP network 202 External network, PS network 203 Fixed network 204 Internal network 301 DNS server (first server) 2 address management device)
302 DNS server (first address management device)
401 network system

Claims (17)

An inquiry information acquisition unit for acquiring inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access a specific external network;
A first address information management device that is provided in the specific external network, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address, and a general external network to which the specific external network is connected Provided for searching for an address corresponding to the inquiry information and transmitting the inquiry information acquired by the inquiry information acquisition unit to a second address information management device that transmits response information indicating the searched address. An inquiry information transmission unit;
A network connection device comprising: a response information transmission unit configured to transmit the response information received from the first address information management device and the second address information management device to the specific terminal device. The network connection device further includes:
2. The network according to claim 1, further comprising: an inquiry destination information transmission unit configured to transmit inquiry destination information indicating that an address information management apparatus as a transmission destination of the inquiry information is the network connection apparatus to the specific terminal device. Connected device.   The inquiry information transmission unit transmits the inquiry information to the second address information management device when the response information cannot be received even if the inquiry information is transmitted to the first address information management device. The network connection device according to claim 1 or 2. The inquiry information acquisition unit further acquires inquiry information of a communication destination address from a general terminal device that is a wireless terminal device or a wired terminal device other than the specific terminal device,
4. The network connection device according to claim 1, wherein the inquiry information transmission unit further transmits the inquiry information acquired from the general terminal device to the second address information management device. 5.   The inquiry information transmission unit transmits the inquiry information every time a predetermined time has elapsed without receiving the response information after transmitting the inquiry information, and an interval for transmitting the inquiry information acquired from the specific terminal device The network connection device according to claim 4, wherein the network connection device is shorter than an interval at which the inquiry information acquired from the general terminal device is transmitted.   The inquiry information transmission unit sequentially transmits the inquiry information to the first address information management device and the second address information management device, and the first address information management device and the second address information management device. If the response information is not received even after a predetermined time has passed since the inquiry information is transmitted to one of the first address information management apparatus, the first address information management apparatus, and the first address information management apparatus, When error information indicating that an address corresponding to the inquiry information has not been retrieved from one of the second address information management devices is received, the other address information management device is not waited for the predetermined time to elapse. The network connection device according to claim 1, wherein the inquiry information is transmitted.   The inquiry information transmission unit transmits the inquiry information to one of the first address information management device and the second address information management device every time a predetermined time elapses without receiving the response information. The inquiry information is transmitted to the other of the first address information management device and the second address information management device, and the inquiry information is responded to from the first address information management device or the second address information management device. 7. The inquiry information according to claim 1, wherein when the error information indicating that the address could not be searched is received, the inquiry information is not transmitted to the address information management apparatus that transmitted the error information. Network connection device.   When the response information transmission unit receives error information indicating that an address corresponding to the inquiry information could not be retrieved from both the first address information management device and the second address information management device. The network connection device according to claim 1, wherein the error information is transmitted to the specific terminal device.   The inquiry information transmission unit waits for a transition to a state where communication with the second address information management device can be started in a state where communication with the second address information management device cannot be started, without waiting for the first information transmission unit. When the inquiry information is transmitted to the first address information management apparatus and the communication with the second address information management apparatus can be started, transmission of the inquiry information to the second address information management apparatus is started. The network connection device according to any one of claims 1 to 8. The network connection device further includes:
A storage unit for storing the identification information of the specific terminal device and the identification information of the general terminal device;
The inquiry information acquisition unit compares the identification information indicated by the inquiry information with the identification information stored in the storage unit, thereby determining whether the transmission source of the inquiry information is the specific terminal device or the general terminal device. The network connection device according to claim 4, wherein it is determined whether or not there is. The network connection device further includes:
The wireless signal including the inquiry information is received from the specific terminal device, the received inquiry information is output to the inquiry information acquisition unit, and the response information is received from the response information transmission unit, and the received The network connection device according to claim 1, further comprising a wireless interface unit for transmitting a wireless signal including response information to the specific terminal device.   The network connection device according to claim 11, wherein the wireless interface unit is a femto base station. The first address information management device searches an address corresponding to the inquiry information received from the network connection device within a range of one or a plurality of addresses stored by itself, and sends response information indicating the searched address. Send to the network connection device, if you can not search, send error information to the network connection device,
The second address information management device searches for an address corresponding to the inquiry information received from the network connection device within a range of one or a plurality of addresses stored by itself, and when the second address information management device fails to find another device The network connection device according to claim 1, further comprising: searching for an address corresponding to the inquiry information, and transmitting response information indicating the searched address to the network connection device. Provided in a specific external network, receives inquiry information of a communication destination address from the network connection device, searches for an address corresponding to the received inquiry information, and transmits response information indicating the searched address to the network connection device Address information management device for
The network connection device is:
An inquiry information acquisition unit for acquiring inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access the specific external network;
Provided in the address information management device and a general external network to which the specific external network is connected to another address information management device that searches for an address corresponding to inquiry information and transmits response information indicating the searched address An inquiry information transmission unit for transmitting the inquiry information acquired by the inquiry information acquisition unit;
An address information management device comprising: a response information transmission unit for transmitting the response information received from the address information management device and the other address information management device to the specific terminal device. A network connection device;
A first address information management device;
The first address information management device is provided in a specific external network, receives inquiry information of a communication destination address from the network connection device, searches for an address corresponding to the received inquiry information, and searches for the searched address. Response information indicating to the network connection device,
The network connection device is:
An inquiry information acquisition unit for acquiring inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access the specific external network;
A second address that is provided in the first address information management device and a general external network to which the specific external network is connected, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address An inquiry information transmission unit for transmitting the inquiry information acquired by the inquiry information acquisition unit to an information management device;
A network system, comprising: a response information transmission unit for transmitting the response information received from the first address information management device and the second address information management device to the specific terminal device. Obtaining inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access a specific external network;
A first address information management device that is provided in the specific external network, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address, and a general external network to which the specific external network is connected The inquiry information acquired by the inquiry information acquisition unit is transmitted to at least one of the second address information management devices provided for searching for an address corresponding to the inquiry information and transmitting response information indicating the searched address. And steps to
Transmitting the response information received from the first address information management device or the second address information management device to the specific terminal device. A network connection program in a network connection device, comprising:
Obtaining inquiry information of a communication destination address from a specific terminal device that is a wireless terminal device permitted to access a specific external network;
A first address information management device that is provided in the specific external network, searches for an address corresponding to inquiry information, and transmits response information indicating the searched address, and a general external network to which the specific external network is connected The inquiry information acquired by the inquiry information acquisition unit is transmitted to at least one of the second address information management devices provided for searching for an address corresponding to the inquiry information and transmitting response information indicating the searched address. And steps to
A network connection program causing the response information received from the first address information management device or the second address information management device to be transmitted to the specific terminal device.

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