JP5041381B2 - Name resolution system, name resolution server, name resolution method, and name resolution program - Google Patents

Description

  The present invention relates to a name resolution system, a name resolution server, a name resolution method, and a name resolution program that perform name resolution in an IPv6 (Internet Protocol Version 6) network environment.

  IPv6 addresses are beginning to be used in the Internet environment.

  In an existing IPv4 (Internet Protocol Version 4) network environment, when a user accesses another device (for example, a web server) from a personal computer, a mechanism is adopted in which a host name is designated and accessed. As another method, in some network environments, an IPv4 address obtained by dividing 32-bit data by 8 bits using “.” (Dot) as a separator and converting the divided data into a decimal value. There is also a mechanism in which (for example, “192.168.0.1”) is used. In this case, there was a scene where the user was operating with an IPv4 address consciousness.

  For example, when referring to the information, “To access the broadband router setting screen, enter“ http://192.168.0.1 ”into the browser and access it” is displayed. Etc.

  A domain name resolution system (hereinafter referred to as DNS) is known as a general mechanism for accessing other devices without being aware of the IPv4 address (that is, specifying a host name). ing. The same applies to the case where an IPv6 address is used.

  For example, Patent Literature 1 describes a method of accessing an information home appliance terminal connected to a home gateway device corresponding to IPv6 service from another terminal using a host name (name information). First, the home gateway device described in Patent Document 1 registers an IP address and a name in a DNS server. Thereafter, a terminal that accesses the information home appliance terminal in the home network system transmits a DNS query to the DNS server. When the DNS server accepts the DNS query, the DNS server searches for the corresponding name information and returns a DNS response including the name information to the terminal. In this way, the terminal can access the information home appliance terminal using the name information.

  Patent Document 2 describes a domain name system server apparatus that processes name resolution at high speed. The domain name system server device described in Patent Document 2 is a device that retrieves communication data that is not addressed to its own device passing through a network and searches for a host name.

  Patent Document 3 describes a setting method that can easily set terminal information in a DNS server database. The setting method described in Patent Document 3 is a method for setting a host name created based on unique information of a network device in a database.

JP 2006-148241 A (paragraph 0044) JP 2009-182508 A (paragraph 0005) Japanese Patent Laying-Open No. 2006-157459 (paragraph 0007)

  In the future, it is considered that the network will become IPv6. The IPv6 address is information obtained by dividing 128-bit data by 16 bits using a separator “:” (colon) and converting the divided data into hexadecimal values. The IPv6 address is expressed, for example, as “2009: 1124: abcd: ef98: a1b2: c3d4: e5f6: fe09”. However, it is difficult for the user to input the IPv6 address expressed in this way with awareness.

  For this reason, access to a terminal requires access by a host name that does not need to be aware of the IPv6 address. Such a problem can be solved by using DNS. Specifically, by using a server (DNS server) that provides a DNS service, it is possible to access a terminal by a host name.

  However, in general, the DNS server operated by the provider does not manage the host name and address data of each device installed in each home. This is because if the host name of each device connected to the network in each home is managed by the DNS server, the database on the DNS server becomes enormous, which increases the operational load. It is.

  In general, a provider distributes a dynamic network address to a home network. For this reason, when managing individual device information in the user's home, it is necessary to update the database in association with a change in the network address, resulting in a problem that the operational load on the server becomes high.

  As described above, when trying to manage the device information in the user's home with the DNS server, problems such as enlargement of the database and correspondence to the network prefix (network address) in the user's home that dynamically changes occur. There is a problem that the operational load becomes high.

  Therefore, an object of the present invention is to provide a name resolution system, a name resolution server, a name resolution method, and a name resolution program that can reduce the operational load of a server used for name resolution.

  The name resolution system according to the present invention is a name that resolves the host name of a terminal device that accesses a device in an IPv6 network having the same network prefix and an access destination device that is connected to the terminal device and that is accessed by the terminal device. A resolution server, wherein the terminal device includes query information transmission means for transmitting query information including a network prefix and the host name of the access destination device to the name resolution server, and the name resolution server includes the host name and the interface identifier. Interface identifier storage means for storing in association, network prefix extraction means for extracting a network prefix included in the inquiry information received from the terminal device, and an interface identifier corresponding to the host name included in the inquiry information An interface identifier extracting unit that extracts from the separate storage unit, an IPv6 address generating unit that generates an IPv6 address that combines the extracted network prefix and the extracted interface identifier, and an IPv6 address that transmits the IPv6 address to the terminal device And a transmission means.

  The name resolution server according to the present invention includes an interface identifier storage unit that associates and stores a host name and an interface identifier, and a terminal device that accesses an apparatus in an IPv6 network having the same network prefix. When the inquiry information including the host name of the device to be accessed is received, the network prefix extraction means for extracting the network prefix included in the inquiry information, and the interface identifier corresponding to the host name included in the inquiry information is stored as the interface identifier An IPv6 address for generating an IPv6 address obtained by combining the interface identifier extraction means extracted from the means, the extracted network prefix, and the extracted interface identifier. And scan generation means, characterized in that a IPv6 address transmitting means for transmitting an IPv6 address to the terminal device.

  When the name resolution method according to the present invention receives inquiry information including a network prefix and a host name of a device accessed by the terminal device from a terminal device accessing the device in the IPv6 network having the same network prefix, The network prefix included in the query information is extracted, and the interface identifier corresponding to the host name included in the query information is extracted from the interface identifier storage unit that stores the host name and the interface identifier in association with each other, and the extracted network prefix and And generating an IPv6 address combined with the extracted interface identifier, and transmitting the IPv6 address to the terminal device.

  A name resolution program according to the present invention is a name resolution program installed in a computer having an interface identifier storage means for storing a host name and an interface identifier in association with each other, and the IPv6 network having the same network prefix as the computer. Network prefix extraction process for extracting a network prefix included in the inquiry information when the inquiry information including the network prefix and the host name of the device accessed by the terminal device is received from the terminal device accessing the device in The interface identifier extraction process for extracting the interface identifier corresponding to the host name included in the information from the interface identifier storage means, the extracted network prefix, and the extracted IPv6 address generation process of generating an IPv6 address by combining the interface identifier, and characterized in that to perform the IPv6 address transmission process of transmitting an IPv6 address to the terminal device.

  According to the present invention, it is possible to reduce the operational load of a server used for name resolution.

It is a block diagram which shows one Embodiment of the name resolution system by this invention. It is explanatory drawing which shows the example at the time of using the name resolution system by embodiment of this invention. It is explanatory drawing which shows the example of a structure in a home network. It is explanatory drawing which shows the example of a DNS query and a DNS response packet. It is explanatory drawing which shows the example of the DNS process at the time of accessing the apparatus in a home network. It is a flowchart which shows the example of the process which a DNS server performs. It is explanatory drawing which shows the example of the DNS process at the time of accessing the apparatus in a home network. It is a block diagram which shows the example of the minimum structure of the name resolution system by this invention. It is a block diagram which shows the example of the minimum structure of the name resolution server by this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an embodiment of a name resolution system according to the present invention. The name resolution system according to the present embodiment includes a name resolution server (hereinafter referred to as a DNS server) 10 and a terminal 20.

  The DNS server 10 is connected to the terminal 20 via the communication network 100. The terminal 20 is connected to the device 30 in the home network 50 which is an IPv6 network environment. The terminal 20 is a broadband router or the like. The device 30 is a network device compatible with IPv6. Examples of the device 30 include communication terminals such as a network compatible hard disk drive and an IP telephone. However, the device 30 is not limited to the above-described device.

  Here, the IPv6 address is composed of 128 bits, and in an IPv6 service by a general provider, the provider (not shown) pays out to each home network 50 using a 64-bit (prefix) as a network address.

  The 64 bits paid out become the upper 64 bits of the IPv6 address of the device 30 in the home network 50 (hereinafter also referred to as a home device). Moreover, it was generated in accordance with the EUI (extended unique identifier) -64 rule defined by IEEE based on the MAC (Media Access Control address) address (48 bits) of each home device in the home network 50. The 64 bits become the lower 64 bits of each home device. In other words, a 128-bit IPv6 address is generated by connecting 64 bits that have been paid out and 64 bits generated based on the MAC address of each home device itself.

  In the above description, the rule for generating the lower 64 bits based on the MAC address of each home device has been described. However, the rule for generating the lower 64 bits is not limited to the above rule. If the value of the lower 64 bits does not overlap with other in-home devices, the lower 64 bits may be determined for each in-home device.

  In the following description, the upper 64 bits in the IPv6 address are referred to as “network prefix”, and the lower 64 bits are referred to as “interface identifier”. That is, the terminal 20 and the device 30 are connected to each other in a home network 50 that is an IPv6 network having the same network prefix.

  In the following description, a case will be described in which two devices of the terminal 20 and the device 30 are connected in the home network 50 and the terminal 20 accesses the device 30. However, the number of devices connected to the home network 50 is not limited to two. There may be three or more devices in the home network 50.

  The terminal 20 includes a control unit 21. The control unit 21 asks the DNS server 10 for inquiry information (hereinafter referred to as a DNS query) including the network prefix of the terminal 20 (that is, the network prefix of the home network 50) and the host name of the device 30 that is the access destination device. Send).

  The DNS server 10 includes a storage unit 11, a DNS query processing unit 12, and a network interface unit 13. The DNS server 10 resolves the host name of the device 30 accessed by the terminal 20.

  The storage unit 11 stores a host name and an interface identifier in association with each other. The host name is identification information for identifying the device. For example, the host name of the broadband router of the home device may be “bbr.home.jp”, and the host name of the network compatible hard disk drive recorder may be “hdd.home.jp”.

  In addition, an interface identifier is defined in advance for each device. For example, the interface identifier of the broadband router that is a home device may be defined as “:: 100”, and the interface identifier of the network compatible hard disk drive recorder may be defined as “:: 200”. At this time, the host name when the interface identifier is “:: 100” is stored in the storage unit 11 in association with “bbr.home.jp”. Similarly, in the storage unit 11, the host name when the interface identifier is “:: 200” is stored in association with “hdd.home.jp”.

  The association between the host name and the interface identifier may be performed by using information predetermined for each device by a terminal-related manufacturer or a provider, for example. In this manner, the storage unit 11 of the DNS server 10 stores host name information (sometimes referred to as pair information) for each interface identifier. The storage unit 11 is realized by, for example, a magnetic disk device provided in the DNS server 10.

  The DNS query processing unit 12 extracts a network prefix included in the DNS query received from the terminal 20. Also, the DNS query processing unit 12 reads an interface identifier corresponding to the host name included in the DNS query from the storage unit 11. Then, the DNS query processing unit 12 generates an IPv6 address obtained by combining the extracted network prefix and the read interface identifier. Finally, the DNS query processing unit 12 transmits the generated IPv6 address to the terminal 20.

  Specifically, when the host name included in the received DNS query exists in the storage unit 11, the DNS query processing unit 12 includes a network prefix part (64 bits) in the DNS query transport protocol (IPv6), DNS, An IPv6 address (128 bits) is generated by connecting a 64-bit interface identifier corresponding to the host name extracted from the storage unit 11 which is the database of the server 10. Then, the DNS query processing unit 12 sends a DNS response to the terminal 20 with the IPv6 address.

  Thus, the network prefix of the user home network is extracted from the DNS query received by the DNS query processing unit 12. Therefore, it is not necessary to store in the database (storage unit 11) of the DNS server 10 association information between the host name of each home device and the 128-bit IPv6 address in all user home networks connected to the communication network 100. . Therefore, the database can be prevented from being enlarged and is not affected by the change of the network prefix of the user home network. Therefore, an appropriate DNS response is possible while reducing the operational load on the server.

  The DNS query processing unit 12 is realized by a CPU of a computer that operates according to a program (name resolution program). For example, the program may be stored in the storage unit 11 of the DNS server 10, and the CPU may read the program and operate as the DNS query processing unit 12 according to the program. Further, the DNS query processing unit 12 may be realized by dedicated hardware.

  The network interface unit 13 transmits and receives data between the DNS server 10 and the terminal 20.

  Next, the operation will be described. FIG. 2 is an explanatory diagram showing an example when the name resolution system according to the present embodiment is used. First, the outline of the operation of the name resolution system according to the present embodiment will be described with reference to FIG.

  The DNS server 10 illustrated in FIG. 2 is the same as the DNS server 10 in FIG. 2 is an IPv6 network accommodated under the broadband router A, and a personal computer (hereinafter referred to as PC_A), A home device (hereinafter also referred to as “home network device”) including a hard disk drive recorder (hereinafter referred to as “HDD recorder A”) is connected. The home network device includes a personal computer, a household electric appliance, and the like.

  The home network illustrated in FIG. 2 (hereinafter referred to as home network X) is also an IPv6 network accommodated under the broadband router X, and in the network, a personal computer (hereinafter referred to as PC_X), A home device including a hard disk drive recorder (hereinafter referred to as HDD recorder X or HDD_X) is connected.

  FIG. 2 shows a home network A and a home network X as examples of the home network. However, many home networks are normally connected on the Internet, and the number of home networks connected to the DNS server 10 is not limited to two, but may be one or three or more. May be.

  Hereinafter, a procedure when the PC_A accesses the HDD recorder A for setting and content browsing will be described. Note that the arrows illustrated in FIG. 2 indicate the direction of access between devices.

  First, PC_A needs to obtain IPv6 address information from the host name of HDD recorder A in order to access HDD recorder A. Therefore, the PC_A transmits a DNS query that is an IPv6 address resolution request to the DNS server 10 in order to obtain IPv6 address information (step S1a). The DNS server 10 returns IPv6 address information for the host name that has received the inquiry to the PC_A by a DNS response (step S2a). The PC_A accesses the HDD recorder A based on the received IPv6 address information (step S3a), and performs communication such as receiving a response from the HDD recorder A (step S4a).

  The procedure when the PC_X accesses the HDD recorder X for setting and content browsing is the same. That is, the PC_X transmits a DNS query to the DNS server 10 (step S1x), and the DNS server 10 returns IPv6 address information to the PC_X (step S2x). Then, PC_X performs communication with HDD recorder X based on the received IPv6 address information (step S3x, step S4x).

  Next, the operation of the name resolution system according to the present embodiment will be described in detail. FIG. 3 is an explanatory diagram illustrating an example of a configuration in the home network X illustrated in FIG. A home network X illustrated in FIG. 3 is an IPv6 network constructed by PC_X, HDD_X, and a broadband router (hereinafter referred to as BBR_X). Further, the interface identifiers of the respective devices for configuring the IPv6 address are assumed to be “INT-PC_X” for PC_X, “:: 200” for HDD_X, and “:: 100” for BBR_X. Further, it is assumed that the network prefix of the home network X configuring IPv6 is “NW_X”. Note that an operation example shown below when the network prefix of the home network X is “NW_X” is referred to as a first operation example.

  Here, a packet structure when the PC_X makes an inquiry to the DNS server 10 will be described with reference to FIG. FIG. 4 is an explanatory diagram illustrating an example of a DNS query transmitted from the PC_X to the DNS server 10 and a DNS response packet transmitted from the DNS server 10 to the PC_X. The packet illustrated in FIG. 4 is an AAAA record defined in DNS for resolving an IPv6 address from a host name. In the example shown in FIG. 4, a packet structure of layer 3 or higher of the network is shown.

  The DNS query is a packet for making an inquiry to the DNS server 10 in order to resolve the IPv6 address from the host name. The DNS query is composed of packets in the order of the IPv6 address of the inquiry destination (Destination IPv6 Address), the IPv6 address of the inquiry source (ie, PC_X) (Source IPv6 Address), and the DNS inquiry content (Question section). In addition, the Question section includes a record name (AAAA record) indicating a query type and a query content (host name).

  The DNS response packet is a packet in which the DNS server 10 that has received the inquiry returns the response content to the inquiry source terminal. The DNS response packet is configured in the order of a reply destination IPv6 Address (Destination IPv6 Address), a reply source IPv6 address (Source IPv6 Address), and a reply to the DNS inquiry (Answer section). Also, the Answer section includes the host name that received the query and the IPv6 Address of the host name.

  For example, when the PC_X accesses to use the web server function of the HDD_X, when the user inputs “http://hdd.home.jp” to the PC_X web browser, the PC_X is set to “hdd.home. An inquiry is made to the DNS server 10 to know (solve) the IPv6 address of jp ″. Then, after resolving the IPv6 address, the PC_X accesses the device indicated by the IPv6 address.

  Hereinafter, the inquiry operation will be described with reference to FIG. FIG. 5 is an explanatory diagram showing an example of DNS processing when the PC_X in the home network X accesses the HDD_X. Note that the PC_X illustrated in FIG. 5 communicates with the DNS server 10 via the BBR_X.

  The contents included in the DNS query packet 41 sent from the PC_X to the DNS server 10 are as follows: Destination IPv6 Address is the IPv6 address of the DNS server 10 [NW-DNS, INT-DNS], Source IPv6 Address is the IPv6 address of the PC_X [NW-X, INT-PC_X], and the inquiry content (Question section) is an AAAA record and “hdd.home.jp”. Here, one point is that the network prefix of Source IPv6 Address is “NW_X” used in the home network X.

  When the DNS server 10 receives the DNS query, the DNS query processing unit 12 generates IPv6 address information for the host name in the AAAA record, and generates a DNS response packet 42. Hereinafter, generation of IPv6 address information, extraction processing of a network prefix necessary for generation of IPv6 address information, and acquisition processing of an interface identifier will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of processing performed by the DNS server 10.

  When the DNS server 10 receives the DNS query (step S11), the DNS query processing unit 12 uses the storage unit 11 (hereinafter referred to as the database) as the zone part (domain part) of the host name “hdd.home.jp” that has received the query. (That is, whether or not it is a self-management zone) (step S12). If it is not the self-managed zone (No in step S12), the DNS query processing unit 12 transfers the DNS query to the upper DNS server 10 to be linked, inquires the IPv6 address information, and acquires the IPv6 address information (step S13).

  On the other hand, if it is the self-managed zone (Yes in step S12), the DNS query processing unit 12 first determines whether or not the received zone portion matches “home.jp” stored in the database ( Step S14). In this example, since the received zone part matches with “home.jp”, in this case (Yes in step S14), the DNS query processing part 12 extracts the interface identifier corresponding to the host name included in the query from the database. (Step S15). In this example, since the host name is “hdd”, the DNS query processing unit 12 extracts the corresponding interface identifier “:: 200” from the database.

  Next, the DNS query processing unit 12 extracts network prefix information from the Source IPv6 Address included in the received DNS query (step S16). In this example, the DNS query processing unit 12 extracts “NW-X” as a network prefix from the DNS query. Then, the DNS query processing unit 12 generates an IPv6 address obtained by combining the extracted network prefix and the interface identifier (step S17). In this example, the DNS query processing unit 12 generates an IPv6 address by connecting “:: 200” extracted as an interface identifier with “NW-X” extracted as a network prefix.

  If the received zone part does not match “home.jp” in step S14 (No in step S14), the DNS query processing unit 12 also performs steps S14 to S17 for other zone parts stored in the database. An IPv6 address is generated by performing the same process as (Step S18).

  The DNS query processing unit 12 generates an IPv6 address based on the data acquired and extracted as described above, and then generates a DNS response packet 42 including the IPv6 address in the Answer section (step S19). It transmits toward PC_X which is a transmission source (step S20).

  The DNS response packet 42 sent from the DNS server 10 to the PC_X includes the IPv6 address [NW-X, INT-PC_X] with the Destination IPv6 Address of PC_X, and the IPv6 address [NW-DNS, INT- with the Source IPv6 Address] of the DNS server 10. DNS]. Also, the Answer section of the DNS response packet 42 includes “hdd.home.jp” that is an inquiry content (that is, a host name) and [NW-X, :: 200] that is IPv6 address information thereof. Yes.

  Accordingly, the PC_X that has received the DNS response packet 42 can access the HDD_X because it knows the IPv6 address for the host name “hdd.home.jp”.

  As described above, according to the present embodiment, the control unit 21 of the terminal 20 whose network prefix accesses the device 30 in the home network 50 sends a DNS query including the network prefix and the host name of the device 30 to the DNS server 10. Send. The DNS query processing unit 12 of the DNS server 10 extracts a network prefix included in the received DNS query. Also, the DNS query processing unit 12 extracts an interface identifier corresponding to the host name included in the DNS query from the storage unit 11. Then, the DNS query processing unit 12 generates an IPv6 address obtained by combining the extracted network prefix and the interface identifier, and transmits the IPv6 address to the terminal 20. Therefore, the operational load on the server used for name resolution can be reduced.

  Specifically, according to this embodiment, the network prefix of the DNS query transmitted from the home network is used for the IPv6 address. This eliminates the need to manage the DNS server database for network prefix changes in the user's home, thus reducing the operational load.

  Further, according to the present embodiment, the host name for each model and the interface identifier are stored in association with each other. Therefore, since it is not necessary to store all the information of each user's house in the database of a DNS server, the enlargement of a database can be suppressed.

  Furthermore, since the name resolution system according to the present embodiment is a mechanism closed in the DNS server, an effect of not affecting other systems can be obtained.

  In addition, by using the name resolution system according to the present embodiment, the user does not need to handle an IP address (IPv6). Therefore, the user can prepare an access environment based on the host name in the home network.

  Also, normally, when performing route selection using the DNS mechanism in the operation of a multi-prefix network in a home, DNS IPv6 network requires complicated route management, so an excessive load is also expected for broadband router development Is done. However, by using the name resolution system according to the present embodiment, the DNS server on the Internet can resolve the address of the in-home device, so that it is not necessary to install the proxy DNS in the broadband router. Therefore, the load is reduced in the development of the broadband router. In other words, the effect of reducing the load can be obtained in the development of the broadband router.

  Furthermore, since it is no longer necessary to install a proxy DNS in the broadband router, an effect of eliminating the security hole anxiety caused by the proxy DNS is also obtained.

  Next, a modification of this embodiment will be described. In the above embodiment, the case where the PC_X accesses the HDD_X indicated by the host name “hdd.home.jp” when the network prefix of the home network is “NW_X” has been described. In the following description, PC_Y of a home network (hereinafter referred to as home network Y) different from home network X illustrated in FIG. 5 is the same host name “hdd.home.jp” as the host name illustrated in the above embodiment. A case of accessing HDD_Y will be described. The operation exemplified below is referred to as a second operation example.

  FIG. 7 shows an example of DNS processing when a personal computer (hereinafter referred to as PC_Y) in a home network (hereinafter referred to as home network Y) accesses a hard disk drive (hereinafter referred to as HDD_Y). It is explanatory drawing. Note that the contents of the storage unit 11 of the DNS server 10 (that is, the database illustrated in FIG. 5) are the same as when the network prefix is “NW_X” (that is, the first operation example). Note that the PC_Y illustrated in FIG. 7 communicates with the DNS server 10 via the broadband router BBR_Y.

  When the PC_Y accesses the HDD_Y, the PC_Y sends a DNS query to the DNS server 10 in order to know the IPv6 address from the host name “hdd.home.jp”. Here, the Source IPv6 Address included in the DNS query packet 43 sent from the PC_Y to the DNS server 10 is “NW-Y”. When the DNS server 10 receives the DNS query packet 43, the DNS query processing unit 12 causes the zone part (domain part) of the host name “hdd.home.jp” that received the inquiry to be stored in the storage unit 11 (that is, the database). It is confirmed whether or not it exists (that is, whether or not it is a self-managed zone).

  In this case, since the received zone part matches with “home.jp”, the DNS query processing part 12 extracts the interface identifier “:: 200” corresponding to the host name “hdd” included in the query from the database. Further, the DNS query processing unit 12 extracts network prefix information “NW-Y” from the Source IPv6 Address included in the received DNS query. Then, the DNS query processing unit 12 generates an IPv6 address obtained by combining the extracted network prefix “NW-Y” and the interface identifier “:: 200”. Then, the DNS query processing unit 12 generates a DNS response packet 44 in which the generated IPv6 address is included in the Answer section, and transmits it to the PC_Y.

  Thus, in the Answer section of the DNS response packet 44 transmitted from the DNS server 10 to the PC_Y, “hdd.home.jp” that is the inquiry content (that is, the host name) and its IPv6 address information [NW− Y, ::: 200]. Accordingly, the PC_Y that has received the DNS response packet 44 can access the HDD_Y because it knows the IPv6 address for the host name “hdd.home.jp”.

  As described above, as shown in the first operation example and the second operation example, according to the present embodiment, it is necessary to change the database of the DNS server 10 even when the network prefix of the home network changes (is different). Absent. That is, even if the network prefix of the home network changes (different), the DNS server 10 can cope with different network prefixes in the same database. Therefore, it can suppress that the database on a DNS server increases.

  Further, from this, even if the network prefix of the home network changes dynamically, it is not necessary to manage the change information of each device, so that the operation load of the DNS server can be reduced.

  Next, an example of the minimum configuration of the name resolution system according to the present invention will be described. FIG. 8 is a block diagram showing an example of the minimum configuration of the name resolution system according to the present invention. The name resolution system according to the present invention is connected to a terminal device 80 (for example, the terminal 20) that accesses a device (for example, the device 30) in an IPv6 network (for example, the home network 50) having the same network prefix, and to the terminal device 80. And a name resolution server 90 (for example, DNS server 10) that resolves the host name of the access destination device (for example, the device 30) that is the device that the terminal device 80 accesses.

  The terminal device 80 includes inquiry information transmission means 81 (for example, the control unit 21) that transmits inquiry information (for example, DNS query) including the network prefix and the host name of the access destination device to the name resolution server 90.

  The name resolution server 90 includes an interface identifier storage unit 91 (for example, the storage unit 11) that stores a host name and an interface identifier in association with each other, and a network prefix that extracts a network prefix included in the inquiry information received from the terminal device 80. An extraction unit 92 (for example, DNS query processing unit 12), an interface identifier extraction unit 93 (for example, DNS query processing unit 12) that extracts an interface identifier corresponding to the host name included in the query information from the interface identifier storage unit 91; , An IPv6 address generating means 94 (for example, DNS query processing unit 12) that generates an IPv6 address that combines the extracted network prefix and the extracted interface identifier; Send IPv6 address transmission means 95 (eg, DNS query processing unit 12) and a.

  With such a configuration, the operational load on the server used for name resolution can be reduced.

  Next, an example of the minimum configuration of the name resolution server according to the present invention will be described. FIG. 9 is a block diagram showing an example of the minimum configuration of the name resolution server according to the present invention. The name resolution server according to the present invention includes an interface identifier storage unit 71 (for example, the storage unit 11) that stores a host name and an interface identifier in association with each other, and an IPv6 network (for example, a home network 50) having the same network prefix. When inquiry information (for example, DNS query) including the network prefix and the host name of the device accessed by the terminal device 60 is received from the terminal device 60 accessing the device (for example, the device 30), the inquiry information is included in the inquiry information. The network prefix extraction means 72 (for example, DNS query processing unit 12) for extracting the included network prefix and the interface identifier corresponding to the host name included in the query information are extracted from the interface identifier storage means 71. Interface identifier extraction means 73 (for example, DNS query processing section 12), IPv6 address generation means 74 (for example, DNS query processing section 12) that generates an IPv6 address that combines the extracted network prefix and the extracted interface identifier. ) And IPv6 address transmission means 75 (for example, DNS query processing unit 12) for transmitting the IPv6 address to the terminal device 60.

  With such a configuration, the operational load on the server used for name resolution can be reduced.

  Note that at least a name resolution system and a name resolution server as described below are also disclosed in any of the embodiments described above.

(1) A terminal device (for example, terminal 20) that accesses a device (for example, device 30) in an IPv6 network (for example, home network 50) having the same network prefix, and a terminal device that is connected to and accessed by the terminal device A name resolution server (for example, DNS server 10) that resolves the host name of an access destination device (for example, device 30) that is a device to be transmitted, and the terminal device includes a network prefix and a host name of the access destination device An interface identifier storage unit (for example, a control unit 21) that transmits information (for example, DNS query) to the name resolution server, and the name resolution server stores the host name and the interface identifier in association with each other. For example, the storage unit 11) and the inquiry received from the terminal device Network prefix extraction means (for example, DNS query processing unit 12) for extracting the network prefix included in the information, and interface identifier extraction means (for example, for extracting the interface identifier corresponding to the host name included in the query information from the interface identifier storage means) DNS query processing unit 12), IPv6 address generation means (for example, DNS query processing unit 12) that generates an IPv6 address that combines the extracted network prefix and the extracted interface identifier, and the IPv6 address as a terminal device Name resolution system comprising IPv6 address transmitting means (for example, DNS query processing unit 12) for transmitting to

(2) The inquiry information transmission unit of the terminal device transmits inquiry information including the IPv6 address of the terminal device as a source address (for example, Source IPv6 Address) to the name resolution server, and the network prefix extraction unit of the name resolution server A name resolution system that extracts a network prefix from a source address included in inquiry information.

(3) The interface identifier storage means stores the lower 64 bits in the IPv6 address in association with the host name, and the interface identifier extraction means stores the 64 bits corresponding to the host name included in the inquiry information from the interface identifier storage means. A name resolution system for extracting and generating an IPv6 address in which the IPv6 address generating means combines the network prefix extracted by the network prefix extracting means and the extracted 64 bits.

(4) An interface identifier storage unit (for example, the storage unit 11) that stores the host name and the interface identifier in association with each other and a device (for example, the device 30) in the IPv6 network (for example, the home network 50) having the same network prefix. When a query information (for example, DNS query) including a network prefix and a host name of a device accessed by the terminal device is received from a terminal device accessing the network device, the network prefix included in the query information is extracted. Prefix extraction means (for example, DNS query processing unit 12) and interface identifier extraction means (for example, DNS) that extracts an interface identifier corresponding to the host name included in the query information from the interface identifier storage means Eri processing unit 12), IPv6 address generating means (for example, DNS query processing unit 12) that generates an IPv6 address that combines the extracted network prefix and the extracted interface identifier, and sends the IPv6 address to the terminal device Name resolution server comprising IPv6 address transmitting means (for example, DNS query processing unit 12).

(5) A name resolution server in which the network prefix extraction unit extracts a network prefix from a source address (for example, Source IPv6 Address) that is an IPv6 address of the terminal device included in the inquiry information received from the terminal device.

  The present invention is preferably applied to a name resolution system that performs name resolution in an IPv6 network environment.

DESCRIPTION OF SYMBOLS 10 DNS server 11 Memory | storage part 12 DNS query process part 13 Network interface part 20 Terminal 21 Control part 30 Apparatus 41,43 DNS query packet 42,44 DNS response packet 50 Home network 100 Communication network

Claims (9)

A terminal device accessing a device in an IPv6 network having the same network prefix;
A name resolution server that is connected to the terminal device and resolves the host name of the access destination device that is the device that the terminal device accesses;
The terminal device
Inquiry information transmitting means for transmitting inquiry information including a network prefix and a host name of the access destination device to the name resolution server,
The name resolution server
Interface identifier storage means for storing a host name and an interface identifier in association with each other;
Network prefix extraction means for extracting a network prefix included in the inquiry information received from the terminal device;
Interface identifier extraction means for extracting an interface identifier corresponding to the host name included in the inquiry information from the interface identifier storage means;
IPv6 address generation means for generating an IPv6 address obtained by combining the extracted network prefix and the extracted interface identifier;
An IPv6 address transmitting means for transmitting the IPv6 address to the terminal device. The inquiry information transmission means of the terminal device
Inquiry information including the IPv6 address of the terminal device as a transmission source address is transmitted to the name resolution server,
The name resolution system according to claim 1, wherein the network prefix extraction unit of the name resolution server extracts a network prefix from a source address included in the inquiry information. The interface identifier storage means stores the lower 64 bits in the IPv6 address in association with the host name,
The interface identifier extraction means extracts the 64 bits corresponding to the host name included in the inquiry information from the interface identifier storage means,
The name resolution system according to claim 1, wherein the IPv6 address generation unit generates an IPv6 address obtained by combining the network prefix extracted by the network prefix extraction unit and the extracted 64 bits. Interface identifier storage means for storing a host name and an interface identifier in association with each other;
When the inquiry information including the network prefix and the host name of the device accessed by the terminal device is received from the terminal device accessing the device in the IPv6 network having the same network prefix, the network prefix included in the inquiry information is Network prefix extraction means to extract;
Interface identifier extraction means for extracting an interface identifier corresponding to the host name included in the inquiry information from the interface identifier storage means;
IPv6 address generation means for generating an IPv6 address obtained by combining the extracted network prefix and the extracted interface identifier;
An IPv6 address transmitting means for transmitting the IPv6 address to the terminal device. The name resolution server according to claim 4, wherein the network prefix extraction unit extracts a network prefix from a source address that is an IPv6 address of the terminal device included in the inquiry information received from the terminal device. When the inquiry information including the network prefix and the host name of the device accessed by the terminal device is received from the terminal device accessing the device in the IPv6 network having the same network prefix, the network prefix included in the inquiry information is Extract and
An interface identifier corresponding to the host name included in the inquiry information is extracted from the interface identifier storage unit that stores the host name and the interface identifier in association with each other,
Generating an IPv6 address that combines the extracted network prefix and the extracted interface identifier;
The IPv6 address is transmitted to the terminal device. A name resolution method, comprising: The name resolution method according to claim 6, wherein when extracting the network prefix, the network prefix is extracted from a transmission source address that is an IPv6 address of the terminal device included in the inquiry information transmitted from the terminal device. A name resolution program mounted on a computer having an interface identifier storage means for storing a host name and an interface identifier in association with each other,
In the computer,
When the inquiry information including the network prefix and the host name of the device accessed by the terminal device is received from the terminal device accessing the device in the IPv6 network having the same network prefix, the network prefix included in the inquiry information is Network prefix extraction processing to extract,
An interface identifier extraction process for extracting an interface identifier corresponding to a host name included in the inquiry information from the interface identifier storage means;
An IPv6 address generation process for generating an IPv6 address obtained by combining the extracted network prefix and the extracted interface identifier; and
The name resolution program for performing the IPv6 address transmission process which transmits the said IPv6 address to the said terminal device. On the computer,
The name resolution program according to claim 8, wherein a network prefix is extracted from an IPv6 address which is a transmission source address of the terminal device included in the inquiry information transmitted from the terminal device in the network prefix extraction process.

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