JP3344238B2 - IPv4-IPv6 communication method and IPv4-IPv6 translation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an IPv4-IPv4
The present invention relates to a communication method and an IPv4-IPv6 conversion device. More specifically, the present invention relates to an IPv4 terminal that uses IPv4 (Internet Protocol version 4) as a communication protocol and an IPv6 (Integrity) as a communication protocol.
The present invention relates to a method and an apparatus for realizing communication between IPv6 terminals using rnet Protocol version 6).

[0002]

2. Description of the Related Art As a method for realizing communication between an IPv4 terminal and an IPv6 terminal, IETF (Internet Engineering) is used.
RFC (Reque) issued by ering Task Force
st For Comments) 1884, “IPv4-mapped I
A method using a “Pv6 address” and an “IPv4-compatible IPv6 address” can be considered. The "IPv4-mapped
The “IPv6 address” is set by setting “0” to the 127th to 48th bits of the 128 bits of the IPv6 address, “1” to the 47th to 32nd bits, and setting the 31st to 0th bits. "IPv4 address"
Is set to the IPv6 address. In addition, the “IP
The “v4-compatible IPv6 address” is an IPv6 address that sets “0” in the 127th to 32nd bits and sets “IPv4 address” in the 31st to 0th bits of the 128 bits of the IPv6 address. .

When performing communication between an IPv4 terminal and an IPv6 terminal, an IPv4 address is fixedly assigned in advance to an IPv6 terminal communicating with the IPv4 terminal. Also, I
In the course of the communication between the Pv4 terminal and the IPv6 terminal, I
Convert P header to IPv4 packet (RFC791)
There is provided a packet conversion device for performing mutual conversion between IPv6 and IPv6 packets (RFC1883). In an IPv4 network, an IPv4 address of an IPv4 terminal and an IPv4 address assigned to the IPv6 terminal are used to make an IP address.
Communicate using v4 packets. In the IPv6 network, the “IPv4-mapped IPv6 address” in which the “IPv4 address of the IPv4 terminal” is set as the IPv6 address of the IPv4 terminal, and the “IPv4 address assigned to the IPv6 terminal” as the IP address of the IPv6 terminal. "IPv4-com
Communication is performed using an IPv6 packet using a "patible IPv6 address". And the packet conversion device,
The “IPv4-mapped IPv6” contained in the IPv6 packet
By converting the “IPv6 address” into an “IPv4 address of an IPv4 terminal” and converting the “IPv4-compatible IPv6 address” into an “IPv4 address assigned to the IPv6 terminal”,
Convert to 4 packets. Conversely, the “IPv4 address of the IPv4 terminal” included in the IPv4 packet is converted into the “IPv4-mapped IPv6 address”, and the “IPv4
By converting the “IPv4 address assigned to the six terminals” into the “IPv4-compatible IPv6 address”, the IPv4 packet is converted into the IPv6 packet. This enables communication between the IPv4 terminal and the IPv6 terminal.

[0004]

In the above method, the IP
Communication between an IPv4 terminal and an IPv6 terminal can be realized by a simple operation of adding a 96-bit fixed pattern to a v4 address or deleting a 96-bit fixed pattern from an IPv6 address. However, the above technique has the following problems. The first problem is that all IPv6 terminals that may communicate with the IPv4 terminal have the IPv4
That is, addresses must be fixedly assigned. This will further consume depleted IPv4 addresses and accelerate depletion. The second problem is that
Since it is not possible to refer to each other's domain information (for example, an IP address corresponding to a domain name) between the IPv4 network and the IPv6 network, the other party can be specified only by the actual IP address instead of the domain name. This depends on whether the other party is using IPv4 as the communication protocol, or
You have to be aware that you are using v6.

Accordingly, an object of the present invention is to provide an IPv6 terminal that does not have a fixed IPv4 address in advance.
Communication between the 4 terminal and the IPv6 terminal is possible, and the other party is designated by the domain name instead of the IP address.
An object of the present invention is to provide a method and an apparatus capable of communicating between a terminal and an IPv6 terminal.

[0006]

According to a first aspect, the present invention provides a communication network system comprising an IPv4 network, an IPv6 network, and an IPv4-IPv6 translator connected to both of them.
A method for communicating between an IPv4 terminal of an IPv4 network and an IPv6 terminal of an IPv6 network, comprising:
When the IPv4 terminal of the IPv4 network queries the IPv4-IPv6 translator for the IP address for the domain name of the IPv6 terminal of the IPv6 network, the IPv4-IPv6 translator sends a request from the DNSv6 server device managing the domain information of the IPv6 network to the domain. DH that obtains an IPv6 address for a name and dynamically allocates an IPv4 address
An IPv4 address corresponding to the IPv6 address is dynamically acquired from a Dynamic Host Configuration Protocol (CP) v4 server device and notified to the IPv4 terminal, and the IPv4 terminal transmits its own IPv4 address to the IPv4 terminal.
Creating an IPv4 packet as a source address and using the notified IPv4 address as an IPv4 destination address, and sending out the IPv4 packet to the IPv4-IPv6 translation device; (b)
The IPv4-IPv6 translation device adds fixed data to the IPv4 source address included in the received IPv4 packet, converts the IPv4 source address into an IPv6 source address,
An IPv6 packet is created from the IPv4 packet by an IP header conversion that converts an IPv4 destination address included in the Pv4 packet into an IPv6 destination address using the corresponding IPv6 address, and is sent to an IPv6 network. (C) The IPv6 terminal , Self I
An IPv6 packet is created with the IPv6 address as the IPv6 source address and the IPv6 source address included in the received IPv6 packet as the IPv6 destination address, and transmitted to the IPv4-IPv6 translator, (d).
The IPv4-IPv6 translation device deletes fixed data from the IPv6 destination address included in the received IPv6 packet, converts the IPv6 destination address into the IPv4 destination address, and uses the IPv6 source address included in the IPv6 packet with the corresponding IPv4 address. The IPv6 is converted by an IP header conversion to an IPv4 source address.
IPv4-IPv4 characterized by creating an IPv4 packet from a packet and sending it out to an IPv4 network
6 communication methods are provided. IPv4 according to the first aspect
-In the IPv6 communication method, the IP of the IPv4 network
Although communication from the v4 terminal to the IPv6 terminal of the IPv6 network can be started, the IPv4 address is dynamically assigned to the IPv6 terminal of the IPv6 network. Consumption of existing IPv4 addresses can be suppressed. Also, IPv4
-Since the IPv6 translator automatically acquires the IP address for the domain name of the IPv6 terminal from the DNSv6 server device, the IPv4 terminal can communicate with the IPv6 terminal by designating the domain name.

[0007] It should be noted that the IPv4-IPv6 conversion device is an
The processes performed between the v4 terminal, the DNSv4 server device, the DHCPv4 server device, the IPv6 terminal, and the DNSv6 server device are all standard technologies described in RFC, and it is not necessary to add a new modification to the device.

In a second aspect, the present invention relates to a communication network system comprising an IPv4 network, an IPv6 network, and an IPv4-IPv6 translator connected to both of them, and an IPv4 terminal of an IPv4 network and an IPv6 terminal of an IPv6 network. A method for communicating with a terminal, wherein (a) an IPv6 terminal of an IPv6 network assigns an IP address to a domain name of an IPv4 terminal of the IPv4 network to the IPv4 network.
-When the IPv6 translator is contacted, the IPv4-I
The Pv6 translation device obtains an IPv4 address for the domain name from a DNSv4 server device that manages domain information of the IPv4 network, and obtains the IPv4 address for the domain name.
The fixed address is added to the address to convert it to an IPv6 address, and the IPv6 address is notified to the IPv6 terminal.
The terminal sets its own IPv6 address as the IPv6 source address and sets the notified IPv6 address as the IPv6 address.
Create an IPv6 packet as a destination address, and
The packet is sent to the Pv4-IPv6 conversion device, and (b) IPv4-
The IPv6 translator removes the fixed data from the IPv6 destination address contained in the received IPv6 packet and
The IPv4 address corresponding to the IPv6 source address included in the IPv6 packet is dynamically acquired from a DHCPv4 server device which converts the IPv4 address to a Pv4 destination address and dynamically allocates the IPv4 address, and obtains the IP address.
The IP address is converted from the IPv6 packet to an IP address by an IP header conversion that converts the IPv4 address to an IPv4 source address.
(c) The IPv4 terminal creates an IPv4 packet using its own IPv4 address as an IPv4 source address and an IPv4 source address included in the received IPv4 packet as an IPv4 destination address. , The IPv4
(D) IPv4-IP to be sent to the 4-IPv6 conversion device
The v6 translator adds the fixed data to the IPv4 source address included in the received IPv4 packet and
The source address is converted to an IPv4 destination address, and an IPv4 destination address included in the IPv4 packet is converted to an IP address corresponding to the IPv4 destination address.
The IPv4 packet is converted to an IPv6 destination address by using an IPv6 address.
An IPv4-IPv6 communication method is characterized in that a v6 packet is created and transmitted to an IPv6 network. In the IPv4-IPv6 communication method according to the above second aspect, the IPv6 terminal side of the IPv6 network
Communication with an IPv4 terminal of a Pv4 network can be started. At this time, an IPv4 address is dynamically assigned to an IPv6 terminal of an IPv6 network.
It is no longer necessary to fixedly assign IPv4 addresses to six terminals in advance, and it is possible to suppress consumption of depleted IPv4 addresses. Also, since the IPv4-IPv6 translator automatically acquires the IP address for the domain name of the IPv4 terminal from the DNSv4 server device,
The Pv6 terminal can communicate with the IPv4 terminal by designating a domain name.

[0009] In a third aspect, the present invention provides:
The IPv4 address corresponding to the IPv6 address of the IPv6 terminal of the 6 network is set to the DH
Means for acquiring an IPv4 address from a CPv4 server, and (b) IP of an IPv6 terminal of an IPv6 network
IP address conversion information holding means for holding the IPv6 address and the acquired IPv4 address in association with each other;
An IP transmitting / receiving means for transmitting / receiving an IPv4 packet to / from the Pv4 network and transmitting / receiving an IPv6 packet to / from the IPv4 network;
The fixed data is added to the IPv4 source address included in the Pv4 packet to convert the IPv4 source address into an IPv6 source address, and the IPv4 destination address included in the IPv4 packet is used for the corresponding IPv6 address held in the IP address conversion information holding unit. An IPv6 packet is created from an IPv4 packet by an IP header conversion for converting the IPv6 destination address into an IPv6 destination address, passed to the IP transmitting / receiving means and transmitted, and fixed data is deleted from the IPv6 destination address contained in the received IPv6 packet to delete the IPv6 destination address. And the IPv6 source address included in the IPv6 packet is converted to a corresponding IPv6 address held in the IP address translation information holding means.
To convert to IPv4 source address using 4 addresses
An IP header conversion unit that creates an IPv4 packet from an IPv6 packet by P header conversion, passes the packet to the IP transmission / reception unit, and transmits the packet. It receives and inquires the DNSv6 server of the IPv6 network to obtain an IPv6 address, and notifies the IPv4 address to the IPv4 terminal of the IPv4 network if the IPv4 address corresponding to the IPv6 address is stored in the IP address conversion information holding means. If the IPv4 address corresponding to the IPv6 address is not held in the IP address translation information holding means, the IPv4 address is obtained by the IPv4 address obtaining means, and IPv6 address with the acquired IP
v4 address is stored in the IP address conversion information storage means in association with the
Notify the IPv4 terminal of the v4 network,
An inquiry about the IP address for the domain name of the IPv4 terminal of the IPv4 network is received from the IPv6 terminal of the IPv6 network, and the D
Inquires the NSv4 server to obtain an IPv4 address, adds fixed data to the IPv4 address, and
v6 address, and the IPv6 address is
Notify the IPv6 terminal of the Pv6 network,
I corresponding to the IPv6 address of the IPv6 terminal of the IPv6 network that has queried the IP address for the domain name of the IPv4 terminal of the IPv4 network
It checks whether the IPv4 address is held in the IP address conversion information holding means, and if not, obtains the IPv4 address by the IPv4 address obtaining means, and associates the IPv6 address with the obtained IPv4 address. An IPv4-IPv6 conversion device characterized by comprising a DNS proxy means for holding the IP address conversion information holding means. According to the IPv4-IPv6 conversion device according to the third aspect,
The IPv4-IPv6 communication method according to the first aspect and the IPv4-IPv6 communication method according to the second aspect can be suitably implemented.

According to a fourth aspect, the present invention provides an I
In the Pv4-IPv6 translation device, the IP address translation information holding means deletes the held IPv6 addresses and IPv4 addresses that have not been referenced for a certain period of time, and sends the deleted IPv4 addresses to the DHCPv4 server of the IPv4 network. There is provided an IPv4-IPv6 conversion device characterized by returning. According to the IPv4-IPv6 conversion device according to the fourth aspect,
Since the unused IPv4 address is returned to the DHCPv4 server, consumption of the IPv4 address can be suppressed.

[0011] In a fifth aspect, the present invention provides an image processing apparatus comprising:
The Pv4-IPv6 translation device further comprises an IPv4 address pool unit for pooling a plurality of IPv4 addresses, and the IP address translation information holding unit is configured to activate the DH of the IPv4 network when the device is started.
Obtain a plurality of IPv4 addresses from the CPv4 server,
Pooled in the IPv4 address pool means,
An IPv4-IP, wherein an IPv4 address corresponding to an IPv6 address of an IPv6 terminal of a Pv6 network is obtained from the IPv4 address pool means.
A v6 converter is provided. IPv5 according to the fifth aspect above
According to the 4-IPv6 translator, rather than acquiring IPv4 addresses one by one from a DHCPv4 server,
Network load can be reduced.

According to a sixth aspect, the present invention provides an I
The Pv4-IPv6 translation device further comprises a DHCPv4 server for dynamically assigning an IPv4 address, and the DHCPv4 server is provided with the IPv4 address.
Provided is an IPv4-IPv6 translator that is used in place of a DHCPv4 server in a network. According to the IPv4-IPv6 conversion device according to the sixth aspect, it is not necessary to separately provide a DHCPv4 server.

According to a seventh aspect, the present invention provides an I
In the Pv4-IPv6 translator, DNSv4 server means for managing domain information of the IPv4 network and D for managing domain information of the IPv6 network.
Further comprising NSv6 server means;
IPv4 server means and DNSv6 server means using the IPv4
4 network DNSv4 server and IPv6
Provided is an IPv4-IPv6 conversion device, which is used in place of a DNSv6 server of a network.
According to the IPv4-IPv6 conversion device according to the seventh aspect, it is not necessary to separately provide a DNSv4 server or a DNSv6 server.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited by this.

First Embodiment FIG. 1 shows an IPv4-I according to a first embodiment of the present invention.
It is a block diagram of the Pv6 conversion device 1a. This IPv4-I
The Pv6 converter 1a is connected to an IPv4 network and an IPv4
IPv4 packet and IP located between 6 networks
By performing the IP header conversion of the v6 packet, the IP
A communication between the v4 terminal and the IPv6 terminal is realized.
, A DNS proxy unit 13, an IPv4 address obtaining unit 14, and an IP address conversion information holding unit 15.

The IP transmission / reception means 10 communicates an IPv4 message with an IPv4 network and an IPv6 network.
It is a means for transmitting and receiving packets and IPv6 packets, and is constituted by an electronic device such as a CPU or a RAM. The IP header conversion means 11 is a means for performing IP header conversion between an IPv4 packet and an IPv6 packet, and is constituted by an electronic device such as a CPU or a RAM. The DNS proxy means 13 includes RFC 1034 and RF
A DNS server or an IPv4 network in an IPv4 network according to the DNS technology described in C1886 or the like.
6 is a means for acquiring domain information from a DNS server in the network, and includes, for example, an electronic device such as a CPU and a RAM. The IPv4 address obtaining means 14
Is a means for acquiring an IPv4 address from a DHCP server in an IPv4 network in accordance with the DHCP technology described in RFC1541, etc.
It is composed of electronic devices such as U and RAM. The IP address conversion information holding means 15 stores the IPv4 address and the I
This is a means for converting a Pv6 address, and is configured by an electronic device such as a RAM, for example. IPv4 address and IP
The correspondence of the v6 address is determined by the IP address conversion table 15
It is held as 1.

FIG. 2 shows an IP address conversion table 151.
FIG. An IPv6 address of an IPv6 terminal that communicates with the IPv4 terminal and an IPv4 address dynamically assigned thereto are registered.

FIG. 3 is a schematic diagram of a communication network system 100 in which the IPv4 network 104 and the IPv6 network 106 are connected via the IPv4-IPv6 conversion device 1a. IPv4 network 104
In addition to the IPv4 terminal 2, the IPv4 network 1
DNSv4 server 3 that manages domain information in 04
And a terminal in the IPv4 network 104
A DHCPv4 server 4 that dynamically allocates v4 addresses is connected. IPv6 network 106
In addition to the IPv6 terminal 5, a DNSv6 server 6 that manages domain information in an IPv6 network is connected. Here, 133.144.95.101 is assigned as the IPv4 address to the IPv4 terminal 2, and 1 :: as the IPv6 address to the IPv6 terminal 5.
It is assumed that 1 is assigned. Also, DHCPv
4 server 4 has 133.144.95.1 to 133.1
It is assumed that 100 IPv4 addresses of 44.95.100 are pooled. Also, the IPv4 terminal 2 and the IPv6 terminal 5 have an IPv4-terminal as a DNS server.
It is assumed that the IPv6 translator 1a has been set. Further, in the IPv4-IPv6 conversion device 1a, a DNSv4 server 3 and a DNSv6 server 6 are set as DNS servers, and a DHCPv server is used as a DHCP server.
It is assumed that four servers 4 have been set.

In FIG. 3, the IPv4 network 1
Although the IP network 04 and the IPv6 network 106 are completely separated, the same applies to a case where the IPv4 network and the IPv6 network coexist in the same physical network.

FIG. 4 and FIG. 5 show that the IPv4 terminal 2
6 is a flowchart of an operation when starting communication to a terminal 5. Since the IPv4 terminal 2 knows the domain name of the IPv6 terminal 5 but does not know the IP address, as shown in FIG. 4, an inquiry message for a domain name corresponding to the domain name of the IPv6 terminal 5 (hereinafter, “message”) A ") is sent to the IPv4-IPv6 translator 1a via the IPv4 network 104, and then waits for a response for a certain period of time. IPv4-IPv6
The IP transmission / reception means 10 of the conversion device 1a receives the message A and passes it to the DNS proxy means 13. The DNS acting unit 13 instructs the IP transmitting / receiving unit 10 to transfer the message A to the DNSv4 server 3, and then waits for a response for a certain period of time. The IP transmitting / receiving means 10 sends the message A
Is transferred to the DNSv4 server 3 via the IPv4 network. DNSv4 server 3 that received message A
Searches for the domain information of the IPv6 terminal 5, but does not return a response to the message A if it is not registered. The DNS proxy unit 13 that has not received a response from the DNSv4 server 3 even after the lapse of a certain time, sends the message A to the DNSv6 server 6 by using the IP transmitting / receiving unit 1.
After instructing and passing 0, a response is waited for a certain time. The IP transmission / reception means 10 transfers the message A to the DNSv6 server 6 via the IPv6 network. The DNSv6 server 6 that has received the message A searches the domain information of the IPv6 terminal 5, and uses the registered domain information of the IPv6 terminal 5 as a response message to the message A (hereinafter, referred to as “message B”). IP
Return to v6 converter 1a. The IP transmitting / receiving means 10 of the IPv4-IPv6 translator 1a, which has received the response from the DNSv6 server 6 within a certain time, receives the message B
Is passed to the DNS proxy unit 13. The DNS proxy means 13
An IPv6 address (1 :: 1) corresponding to the domain name of the IPv6 terminal 5 is obtained from the message B and passed to the IP address conversion information holding means 15. The IP address conversion information holding means 15 stores the IP address conversion table 1 using the IPv6 address (1 :: 1) of the IPv6 terminal 5 as a key.
51, and if the corresponding entry is registered,
The IPv4 address of the entry is stored in the DNS proxy unit 13
To return. On the other hand, if the corresponding entry is not registered, the fact is notified to the DNS acting means 13.

From the IP address conversion information holding means 15 to I
Upon receiving the Pv4 address, the DNS acting unit 13 creates a message (hereinafter, referred to as "message E") notifying the IPv4 address as an IPv4 address corresponding to the domain name of the IPv6 terminal 5, and transmits this message to the IP transmitting / receiving unit. Hand over to 10. The IP transmitting / receiving means 10 transmits the message E to the IPv4 terminal 2 via the IPv4 network. On the other hand, IP address conversion information holding means 1
Received notification that the entry is not registered from 5
The proxy unit 13 sends an IP address to the IPv4 address acquiring unit 14.
After instructing acquisition of the v4 address, wait for a response for a certain period of time. The IPv4 address obtaining means 14 obtains an IPv4 address obtaining message (hereinafter, referred to as “message C”).
After instructing the IP transmission / reception means 10 to transfer this to the DHCPv4 server 4, and waiting for a response for a certain period of time. The IP transmitting / receiving means 10 transmits the message C
It transmits to the DHCPv4 server 4 via the v4 network.

The DHCPv4 server 4 receiving the message C sends the IPv6 address (1 :: 1) of the IPv6 terminal 5
Is assigned an IPv4 address (here, 133.14).
It is assumed that 4.95.1 has been assigned. ), And returns an IPv4 address assignment message (hereinafter, referred to as “message D”).

IP transmitting / receiving means 1 receiving message D
0 passes the message D to the IPv4 address acquisition means 14. The IPv4 address acquiring means 14 sends the message D
And obtains the IPv4 address (133.144.95.1) from the DNS server 13 and notifies the DNS proxy 13 of the address. The DNS acting means 13 sends the IPv4 address (133.144.95.
1) the IP corresponding to the domain name of the IPv6 terminal 5
A message E to be notified as an address is created and passed to the IP transmitting / receiving means 10. The IP transmitting / receiving means 10 transmits the message E to the IPv4 terminal 2 via the IPv4 network. In addition, the DNS proxy means 13 uses DHCP
IPv4 address acquired from the v4 server 4 (133.
144.95.1) is associated with the IPv6 address (1 :: 1) of the IPv6 terminal 5 and passed to the IP address conversion information holding means 15. IP address conversion information holding means 15
Creates a new entry in the IP address conversion table 151 and stores the IPv4 address (133.144.95.
1) and the IPv6 address (1 :: 1) of the IPv6 terminal 5
Register the correspondence. Note that the IP address conversion table 1
The entry 51 is deleted if it is not referenced for a certain period of time, and the IPv4 address (133.144.95.1) is returned to the DHCPv4 server 4.

As shown in FIG. 5, the IPv4 terminal 2
The IPv4 address notified by the message E from the Pv4-IPv6 translation device 1a (133.144.95.
1) is set in the IPv4 destination address field of the IPv4 packet and the own IPv4 address (13
An IPv4 packet in which 3.144.95.101) is set in the IPv4 source address field is sent to the IPv4-IPv6 translator 1a via the IPv4 network.
Send to The IP transmission / reception unit 10 of the IPv4-IPv6 conversion device 1a passes the received IPv4 packet to the IP header conversion unit 11. The IP header conversion means 11
The IPv4 address (133.144.95.101) is extracted from the IPv4 source address field of the Pv4 packet, and the above-mentioned fixed pattern of 96 bits is added to the 128-bit “IPv4-mapped IPv6 address” (:: FFFF: 133). .144.95.101)
And set this in the IPv6 source address field of the IPv6 packet. Further, the IP header conversion means 11 converts the IPv4 address (133.144.9) from the IPv4 destination address field of the IPv4 packet.
5.1) is taken out and passed to the IP address conversion information holding means 15. IP address conversion information holding means 15
Refers to the IP address conversion table 151, and
An IPv6 address (1 :: 1) corresponding to the v4 address (133.144.95.1) is obtained and passed to the IP header conversion means 11. The IP header conversion means 11 uses the IPv6
IPv6 in the IPv6 destination address field of the packet
Address (1 :: 1) is set. Then, the IPv6 packet created by performing the IP header conversion is transferred to the IP transmission / reception unit 10. The IP transmitting / receiving means 10
The Pv6 packet is transmitted over the IPv6 network via the I6
It transmits to the Pv6 terminal 5. As described above, the IPv4 terminal 2
Can start communication with the IPv6 terminal 5.

FIG. 6 and FIG. 7 show that the IPv6 terminal 5
4 is a flowchart of an operation when starting communication to four terminals 2. Since the IPv6 terminal 5 knows the domain name of the IPv4 terminal 2 but does not know the IP address, as shown in FIG. 6, a query message for a domain name corresponding to the domain name of the IPv4 terminal 2 (hereinafter, “message”) K ”) via the IPv6 network 106 to the IPv4-IPv6 translator 1a, and then waits for a response for a certain period of time. IPv4-IPv6
The IP transmission / reception means 10 of the conversion device 1a receives the message K and passes it to the DNS proxy means 13. The DNS acting means 13 instructs the IP transmitting / receiving means 10 to transfer the message K to the DNSv6 server 6, and then waits for a response for a certain period of time. The IP transmitting / receiving means 10 transmits the message K
Is transferred to the DNSv6 server 6 via the IPv6 network. DNSv6 server 6 that received message K
Searches for the domain information of the IPv4 terminal 2, but does not return a response to the message K if it is not registered. The DNS proxy unit 13 that has not received a response from the DNSv6 server 6 even after a certain period of time has passed, the IP transmitting / receiving unit 1 transfers the message K to the DNSv4 server 3.
After instructing and passing 0, a response is waited for a certain period of time. The IP transmission / reception means 10 transfers the message K to the DNSv4 server 3 via the IPv4 network. The DNSv4 server 3 that has received the message K searches the domain information of the IPv4 terminal 2 and uses the registered domain information of the IPv4 terminal 2 as a response message to the message K (hereinafter, referred to as “message L”). IP
Return to v6 converter 1a. The IP transmitting / receiving means 10 of the IPv4-IPv6 translator 1a, which has received the response from the DNSv4 server 3 within a certain time, sends the received message L
Is passed to the DNS proxy unit 13. The DNS proxy means 13
From the message L, an IPv4 address (133.144.95.10) corresponding to the domain name of the IPv4 terminal 2
Obtain 1).

Next, the DNS proxy unit 13 passes the IPv6 address (1 :: 1) of the IPv6 terminal 5 to the IP address conversion information holding unit 15. The IP address conversion information holding unit 15 uses the IPv6 address (1 :: 1) of the IPv6 terminal 5 as a key to set the IP address conversion table 1
51, and notifies the DNS substituting means 13 whether or not the corresponding entry is registered. I of IPv6 terminal 5
Upon receiving the notification that the entry corresponding to the Pv6 address (1 :: 1) has not been registered, the DNS acting unit 13
IPv4 address acquisition means 1 for IPv4 address acquisition
After instructing step 4, wait for a certain period of time for a response. The IPv4 address acquisition means 14 creates an IPv4 address acquisition message (hereinafter, referred to as “message M”), instructs the IP transmission / reception means 10 to transfer the message to the DHCPv4 server 4, and then passes the message. Wait for time response. IP
The transmission / reception unit 10 transmits the message M to the DHCPv4 server 4 via the IPv4 network. The DHCPv4 server 4 that has received the message M assigns an IPv4 address to the IPv6 address (1 :: 1) of the IPv6 terminal 5 (here, it is assumed that 133.144.95.1 is assigned), and the IPv4 address is assigned. An address assignment message (hereinafter, referred to as “message N”) is returned. The IP transmitting / receiving means 10 having received the message N passes the message N to the IPv4 address acquiring means 14. The IPv4 address obtaining unit 14 obtains the IPv4 address (133.144.95.1) from the message N and notifies the DNS proxy unit 13 of the IPv4 address. The DNS acting means 13 is a DHCPv4
IPv4 address acquired from the server 4 (133.14
4.95.1) is associated with the IPv6 address (1 :: 1) of the IPv6 terminal 5 and passed to the IP address conversion information holding means 15. IP address conversion information holding means 15
Creates a new entry in the IP address conversion table 151 and sets the IPv4 address (133.144.95.
1) and the IPv6 address (1 :: 1) of the IPv6 terminal 5
Register the correspondence. Note that the IP address conversion table 1
The entry 51 is deleted if it is not referenced for a certain period of time, and the IPv4 address (133.144.95.1) is returned to the DHCPv4 server 4.

A notification that an entry corresponding to the IPv6 address (1 :: 1) of the IPv6 terminal 5 is registered is received, or registration of an entry corresponding to the IPv6 address (1 :: 1) of the IPv6 terminal 5 is performed. Upon completion, the DNS proxy unit 13 sets the IPv4 terminal 2
“IPv4-mapped IPv6 address” with the address (133.144.99.501) set (:: FFFF:
133.144.95.101) as a message notifying the IP address corresponding to the domain name of the IPv4 terminal 2 (hereinafter referred to as “message P”), and transferring the message to the IPv6 terminal 5. It instructs and passes to the IP transmitting / receiving means 10. The IP transmitting / receiving means 10 transmits the message P to the IPv6 terminal 5 via the IPv6 network.
Send to

As shown in FIG. 7, the IPv6 terminal 5
IPv6 notified from the Pv4-IPv6 conversion device 1a
Address (:: FFFF: 133.144.95.10
1) is set in the IPv6 destination address field of the IPv6 packet, and the own IPv6 address (1 :: 1) is set.
With IPv6 set in the IPv6 source address field
6 packets over an IPv6 network
It transmits to the 4-IPv6 conversion device 1a. IPv4-IP
The IP transmitting / receiving means 10 of the v6 converter 1a
The Pv6 packet is passed to the IP header conversion means 11. IP
The header converting means 11 converts the IPv6 address (:: FF) from the IPv6 destination address field of the IPv6 packet.
FF: 133.144.95.101), and the above-mentioned fixed pattern of 96 bits is deleted to remove a 32-bit IPv4 address ”(133.144.95.10).
1) and set this in the IPv4 destination address field of the IPv4 packet. Further, the IP header conversion unit 11 extracts the IPv6 address (1 :: 1) from the IPv6 transmission address field of the IPv6 packet, and passes this to the IP address conversion information holding unit 15. The IP address conversion information holding unit 15 refers to the IP address conversion table 151, and reads the IPv4 address (133.1) corresponding to the IPv6 address (1 :: 1).
44.95.1) is obtained and passed to the IP header conversion means 11. The IP header conversion means 11 determines whether the IP header
In the IPv4 source address field, enter the IPv4 address (1
33.144.95.1) is set. Then, the IPv4 packet created by performing the IP header conversion is transferred to the IP transmitting / receiving means 10. IP transmitting / receiving means 10
Transmits an IPv4 packet to the IPv4 terminal 2 via the IPv4 network. As described above, IPv6
Communication from the terminal 5 to the IPv4 terminal 2 can be started.

Although the case where the IPv4 domain information is registered in the DNSv4 server 3 has been described above, the IPv4 domain information may be registered in the DNSv6 server 6. In this case, IPv4-IPv6
The conversion device 1a uses a DNSv
6 to obtain IPv4 domain information by communicating with the server 6. Similarly, the IPv6 domain information is
It may be registered in the NSv4 server 3. in this case,
The IPv4-IPv6 translator 1a communicates with the DNSv4 server 3 using the IPv4 protocol, thereby
Obtain Pv6 domain information.

Second Embodiment FIG. 8 shows an IPv4-I according to a second embodiment of the present invention.
It is a block diagram of the Pv6 converter 1b. This IPv4-I
The Pv6 translator 1b has a configuration obtained by adding an IPv4 address pool unit 16 to the IPv4-IPv6 translator 1a of FIG. When the IPv4-IPv6 translator 1b is started up, the IPv4 address acquiring means 14 transmits the DHC
A plurality of IPv4 addresses are acquired collectively from the Pv4 server 4 and pooled in the IPv4 address pool means 16. Then, when the communication between the IPv4 terminal 2 and the IPv6 terminal 5 starts, the IPv4 address acquiring means 14
Obtains an IPv4 address from the IPv4 address pool unit 16. This IPv4-IPv6 conversion device 1b
Is more effective than acquiring IPv4 addresses one by one from the DHCPv4 server 4.
4 can be reduced.

Third Embodiment FIG. 9 shows an IPv4-I according to a third embodiment of the present invention.
It is a block diagram of the Pv6 converter 1c. This IPv4-I
The Pv6 translator 1c replaces the IPv4 address acquisition means 14 of the IPv4-IPv6 translator 1a of FIG.
This is a configuration in which HCPv4 server means 17 is provided. This I
If the Pv4-IPv6 conversion device 1c is used, DHCPv
There is no need to provide four servers 4 separately.

Fourth Embodiment FIG. 10 is a block diagram showing an IPv4 according to a fourth embodiment of the present invention.
FIG. 3 is a configuration diagram of an IPv6 translator 1d. This IPv4-
The IPv6 translator 1d adds the DNSv4 server means 18 and the DNSv6 to the IPv4-IPv6 translator 1a of FIG.
This is a configuration in which server means 19 are added. This IPv4
If the IPv6 translator 1d is used, there is no need to provide the DNSv4 server 3 or the DNSv6 server 6 separately.

[0033]

According to the IPv4-IPv6 communication method and the IPv4-IPv6 conversion apparatus of the present invention, even if an IPv4 terminal is not fixed and an IPv4 address is previously allocated, it is possible to use the method.
Communication between the IPv4 terminal and the IPv6 terminal can be performed. Furthermore, since the other party can be specified by the domain name instead of the actual IP address, whether the other party uses IPv4 as a communication protocol or whether the other party uses IPv4
6 can be communicated without being conscious of whether it is used.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an IPv4-IPv4 address according to a first embodiment of the present invention.
It is a block diagram of a 6 conversion apparatus.

FIG. 2 is a configuration diagram of an IP address conversion table.

FIG. 3 is a configuration diagram of a communication network system according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating an IPv4-IPv4 address according to the first embodiment of the present invention.
6 is a flowchart in the case of starting communication from an IPv4 terminal to an IPv6 terminal via a 6 conversion device.

FIG. 5 is a flowchart continued from FIG. 4;

FIG. 6 is a diagram illustrating an IPv4-IPv4 address according to the first embodiment of the present invention.
6 is a flowchart in the case of starting communication from an IPv6 terminal to an IPv4 terminal via a 6-conversion device.

FIG. 7 is a flowchart continued from FIG. 6;

FIG. 8 is a diagram illustrating an IPv4-IPv4 address according to a second embodiment of the present invention.
It is a block diagram of a 6 conversion apparatus.

FIG. 9 is a diagram illustrating an IPv4-IPv4 address according to a third embodiment of the present invention.
It is a block diagram of a 6 conversion apparatus.

FIG. 10 shows an IPv4-IP according to a fourth embodiment of the present invention.
It is a block diagram of a v6 converter.

[Explanation of symbols]

1a, 1b, 1c, 1d ... IPv4-IPv6 conversion device, 2 ... IPv4 terminal, 3 ... DNSv4 server, 4 ... D
HCPv4 server, 5 ... IPv6 terminal, 6 ... DNSv6
Server, 10: IP transmitting / receiving means, 11: IP header converting means, 13: DNS acting means, 14: IPv4 address obtaining means, 15: IP address conversion information holding means, 16
... IPv4 address pool means, 17 ... DHCP server means, 18 ... DNSv4 server means, 19 ... DNSv6
Server means.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichi Hamamoto 890-12 Kashimada, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture, Hitachi, Ltd. 890-12, Hitachi, Ltd.Information and Communication Development Headquarters (72) Inventor Riichi Yasue 890-12, Kashimada, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Hitachi, Ltd.Information and Communication Development Headquarters (56) References JP Hei 10-23072 (JP, A) JP-A Hei 10-154994 (JP, A) Masatoshi Takamura et al., "Seamless IPv4 / IPv6 Intercommunication System", Information Processing Society of Japan Research Report, Information Processing Society of Japan, 1996 September 27, Vol. 96, No. 95, pp. 79-84, 96-DPS-78-14 Takada, NEWS WATCH Internet IPv6-IPv4 connection technology is one after another DEC, such as Hitachi to Defeat spark, Nikkei Communication, Nikkei BP, Inc., February 16, 1998, No. 264, page 92 E. Gilligan, et al. , "Transition Mec hanisms for IPv6 H osts and Routers", RFC1933 (Network Wor king Group Request for Comments: 1933), IETF, 4 May 1996 (58) investigated the field (Int.Cl. ^7, DB name) H04L 12 / 56 H04L 12/66 H04L 12/46 H04L 29/06 G06F 13/00

Claims (20)

(57) [Claims] At least one IPv4 device using IPv4 as a communication protocol and at least one IPv6 device using IPv6 are connected via a network to an IPv4-to-IPv6 translation device, wherein an IPv4 or IPv4 conversion device is connected to the network. and receiving means for transmitting and receiving messages using IPv6, via said transmitting and receiving means, wherein the optional IPv6 device
Receiving an inquiry message for the domain information of another device connected via the network, the inquiry message for the domain information of the other device sends to the DNS server that manages the IPv6 domain information, domain information of the other device if it does not receive the message in response to, DNS server that sends to the DNS server, which manages the IPv4 domain information for managing the IPv4 domain information inquiry message domain information of the other device
When receiving a message that responds to the domain information of the other device from the server, the message included in the response message
The IPv4 address of another device is converted into an IPv6 address, and the IPv6 address is converted into domain information of the other device.
IPv4-IPv6 converting apparatus; and a DNS substituting means for transmitting a message notifying a broadcast to the arbitrary IPv6 device. 2. An IPv4-IPv6 conversion device connected via a network to at least one IPv4 device using IPv4 as a communication protocol and at least one IPv6 device using IPv6 as a communication protocol. and receiving means for transmitting and receiving messages using IPv6, via said transmitting and receiving means, wherein the optional IPv6 device
Receiving an inquiry message for the domain information of another device connected via a network, and transmits an inquiry message for the domain information of the other device to the first DNS server that manages the IPv6 domain information, the other < If a message that responds to the domain information of the device is not received from the first DNS server, a query message for the domain information of the other device is transmitted to a second DNS server that manages IPv4 domain information. , Other
The message responding to the domain information of the second device
, The IPv4 address of the other device included in the response message is converted into an IPv6 address, and a message notifying the IPv6 address as domain information of the other device is received by the arbitrary IP address.
An IPv4-IPv6 conversion device, comprising: a DNS proxy means for transmitting to a v6 device. 3. An IPv4 network to which an IPv4 device using IPv4 as a communication protocol is connected,
IPv6 to which an IPv6 device using IPv6 is connected
An IPv4-IPv6 conversion device connected to a network, comprising: a transmitting / receiving unit that transmits / receives a message to / from the IPv4 network and the IPv6 network using IPv4 or IPv6; Any IPv4 sent from any IPv6 device
Receiving the inquiry message of the device domain information,
Sending a query message for domain information of the arbitrary IPv4 device to a DNS server that manages domain information in the IPv6 network,
When a message for responding to the domain information of the device is not received within a predetermined time, a query message for the domain information of the arbitrary IPv4 device is transmitted to a DNS server that manages the domain information in the IPv4 network, and the arbitrary When a message responding with the domain information of the IPv4 device is received, 96 is added to the IPv4 address of the arbitrary IPv4 device included in the response message.
A fixed pattern of bits is set and converted to an IPv6 address, and the IPv6 address is converted to the arbitrary IPv4 address.
A message for notifying the arbitrary IPv6 device as an IP address corresponding to a domain name of the device;
An IPv4-IPv6 conversion device, comprising: a DNS proxy unit for transmitting to a v6 network. 4. An IPv4 network to which an IPv4 device using IPv4 as a communication protocol is connected,
IPv6 to which an IPv6 device using IPv6 is connected
An IPv4-IPv6 conversion device connected to a network, comprising: a transmitting / receiving unit that transmits / receives a message to / from the IPv4 network and the IPv6 network using IPv4 or IPv6; Any IPv4 sent from any IPv6 device
Receiving the inquiry message of the device domain information,
The inquiry message for the domain information of the arbitrary IPv4 device is transmitted to a first device connected to the IPv6 network.
If the message that transmits the domain information of the arbitrary IPv4 device is not received from the first DNS server within a predetermined time, the inquiry message of the domain information of the arbitrary IPv4 device is transmitted to the DNS server of the arbitrary IPv4 device. When a message transmitted to the second DNS server connected to the IPv4 network and responding with the domain information of the arbitrary IPv4 device is received from the second DNS server, the arbitrary IPv4 device included in the response message A fixed pattern of 96 bits is set to the IPv4 address of the IPv4 address and converted to an IPv6 address, and the IPv6 address is set as an IP address corresponding to the domain name of the arbitrary IPv4 device.
6. An IPv4-IPv6 conversion device, comprising: a DNS proxy means for transmitting a message notifying the six devices to the IPv6 network. 5. The IPv4-IPv6 translation device according to claim 1, wherein said DNS proxy means transmits said arbitrary IPv6 device to said arbitrary IPv6 device.
receiving an inquiry message for an IPv6 address corresponding to the domain name of the v4 device
Pv4-IPv6 conversion device. 6. The IPv4-IPv6 translation device according to claim 1, wherein said DNS proxy means sends an inquiry message for an IPv4 address corresponding to a domain name of said arbitrary IPv4 device.
An IPv4-to-IPv6 translation device, which transmits IPv4 domain information to a DNS server that manages the IPv4 domain information, and receives from the DNS server a message that responds to the IPv4 address of the arbitrary IPv4 device. 7. An IPv4-IPv6 conversion device connected via a network to at least one IPv4 device using IPv4 as a communication protocol and at least one IPv6 device using IPv6 as a communication protocol. and receiving means for transmitting and receiving messages using IPv6, via said transmitting and receiving means, wherein the optional IPv6 device
A DNS server that manages IPv6 domain information, receives a query message for an IP address corresponding to a domain name of another device connected via a network, and sends a query message for an IP address corresponding to the domain name; When a message is transmitted to the DNS server that manages the information and receives a message that responds to the IPv4 address corresponding to the domain name ,
Converting said IPv4 address contained in the response message to the IPv6 address, before the IPv6 address
A DN transmitting a message to be notified as an IP address corresponding to the domain name to the arbitrary IPv6 device
IPv4-IP characterized by having an S proxy means
v6 converter. 8. A DNS proxy device connected via a network to at least one IPv4 device using IPv4 as a communication protocol and at least one IPv6 device using IPv6, and using IPv4 or IPv6 for the network. and receiving means for transmitting and receiving messages using, via said transmitting and receiving means, wherein the optional IPv6 device
Receiving an inquiry message for the domain information of another device connected via the network, the inquiry message for the domain information of the other device sends to the DNS server that manages the IPv6 domain information, domain information of the other device if it does not receive the message in response to, DNS server that sends to the DNS server, which manages the IPv4 domain information for managing the IPv4 domain information inquiry message domain information of the other device
When receiving a message that responds to the domain information of the other device from the server, the message included in the response message
Generating an IPv6 address from an IPv4 address of another device, and using the IPv6 address as a domain of the other device;
A proxy means for transmitting a message to be notified as information to the arbitrary IPv6 device.
S proxy device. 9. A DNS proxy device connected via a network to at least one IPv4 device using IPv4 as a communication protocol and at least one IPv6 device using IPv6, wherein IPv4 or IPv6 is used for the network. and receiving means for transmitting and receiving messages using, via said transmitting and receiving means, wherein the optional IPv6 device
A DNS server that manages IPv6 domain information, receives a query message for an IP address corresponding to a domain name of another device connected via a network, and sends a query message for an IP address corresponding to the domain name; When a message is transmitted to the DNS server that manages the information and receives a message that responds to the IPv4 address corresponding to the domain name ,
Converting said IPv4 address contained in the response message to the IPv6 address, before the IPv6 address
A proxy transmitting means for transmitting a message to be notified as an IP address corresponding to the domain name to the arbitrary IPv6 device. 10. little using the first version of at least one first device and the IP protocol of the second version of using the IP protocol as a communication protocol
A transceiving device connected to at least one second device via a network, for transmitting and receiving messages to and from the network using the first version of the IP protocol or the second version of the IP protocol means, via said transceiver means, said network from said first device
Receiving a domain information inquiry message of another device connected via the network, and transmitting the domain information inquiry message of the other device to a server that manages domain information of the device that uses the first version of the IP protocol. If a message that transmits and does not receive a response to the domain information of the other device is received, a query message for the domain information of the other device is used to manage the domain information of the device that uses the second version of the IP protocol. Sending to the server, the second version of I
Manages domain information for devices that use the P protocol
When receiving a message that responds to the domain information of the other device from the server, the IP address of the second version of the other device included in the response message is converted into a corresponding IP address of the first version. ,
A conversion unit that transmits a message notifying the IP address of the first version as domain information of the another device to the first device. 11. The conversion device according to claim 10, wherein the DNS acting unit receives a query message for an IP address of a first version corresponding to a domain name of the second device from the first device. A conversion device characterized by performing. 12. The conversion device according to claim 10, wherein the DNS acting means transmits an inquiry message of a second version of an IP address corresponding to a domain name of the second device to the second version. Transmitting domain information of a device using the IP protocol to a server that manages the domain information, and transmitting a second version of the IP address of the second device;
A conversion device for receiving a message responding to an address from the server. 13. little use the IP protocol of the first version of at least one first device and the second version of using the IP protocol as a communication protocol
A transceiving device connected to at least one second device via a network, for transmitting and receiving messages to and from the network using the first version of the IP protocol or the second version of the IP protocol means, via said transceiver means, said network from said first device
Receiving an inquiry message of an IP address corresponding to a domain name of another device connected via the network, and transmitting an inquiry message of an IP address corresponding to the domain name to the device using the first version of the IP protocol. Transmitting to a server that manages domain information and a server that manages domain information of a device that uses the second version of the IP protocol,
Upon receiving a message that responds with a second version of the IP address corresponding to the domain name, the second version converts the second version of the IP address included in the response message into a first version of the IP address, and the domain value 1 of the version of the IP address
Conversion device and having a DNS substituting means for transmitting a message notifying the IP address corresponding to the over arm to the first device. 14. An IPv6 device using IPv6 as a communication protocol and an IPv4 device using IPv4 as a communication protocol.
A method of notifying an IP address , comprising: receiving an inquiry message of domain information of an arbitrary IPv4 device from an arbitrary IPv6 device;
Inquiry message for domain information of v4 device
If the server transmits the v6 domain information to the server that manages the IPv6 domain information and does not receive the message that replies the domain information of the arbitrary IPv4 device, the inquiry message about the domain information of the arbitrary IPv4 device is sent to the server that manages the IPv4 domain information. When transmitting and receiving a message responding with the domain information of the arbitrary IPv4 device, the IPv4 address of the arbitrary IPv4 device included in the response message is converted into an IPv6 address, and
Pv6 address is the IP address of any IPv4 device.
Notification method characterized by transmitting a message notifying the scan to the arbitrary IPv6 device. 15. An IPv6 device using IPv6 as a communication protocol and an IPv4 device using IPv4 as a communication protocol.
A method of notifying an IP address , comprising: receiving an inquiry message of domain information of an arbitrary IPv4 device from an arbitrary IPv6 device;
Inquiry message for domain information of v4 device
If a message transmitted to the first DNS server that manages the v6 domain information and the response of the domain information of the arbitrary IPv4 device is not received from the first DNS server, the domain information of the arbitrary IPv4 device is Sending a query message to a second DNS server which manages IPv4 domain information, and sending a message responding with domain information of the arbitrary IPv4 device to the second DNS server;
If received from the server, the IPv4 address of the arbitrary IPv4 device included in the response message
6. A notification method, comprising: converting a message to an arbitrary IPv6 device; and transmitting a message notifying the IPv6 address as an IP address of the arbitrary IPv4 device to the arbitrary IPv6 device. 16. The notification method according to claim 14, wherein the IPv6 device corresponding to the domain name of the arbitrary IPv4 device is transmitted from the arbitrary IPv6 device.
A notification method characterized by receiving an address inquiry message. 17. The notification method according to claim 14, wherein an inquiry message of an IPv4 address corresponding to a domain name of the arbitrary IPv4 device is transmitted to a DNS server managing IPv4 domain information, A notification method, comprising: receiving, from the DNS server, a message responding to an IPv4 address of an arbitrary IPv4 device. 18. An IPv6 device using IPv6 as a communication protocol and an IPv4 device using IPv4
A method for notifying an IP address to the IPv6 device corresponding to the domain name of the IPv4 device by the conversion device connected via a network to bets, the network originating from any IPv6 device
Receiving the IP address query message corresponding to the domain name of another apparatus connected via the de
When an inquiry message of an IP address corresponding to the main name is transmitted to a DNS server that manages IPv6 domain information and a DNS server that manages IPv4 domain information , and when a message responding with an IPv4 address corresponding to the domain name is received, A fixed pattern of 96 bits is set in the IPv4 address included in the response message and converted to an IPv6 address, and the IPv6 address is converted to an IPv6 address corresponding to the domain name.
The arbitrary IP message to notify the P address
A notification method, wherein the notification method is transmitted to a v6 device . 19. A first device that uses a first version of the IP protocol as a communication protocol is provided with an IP of a second device that uses a second version of the IP protocol.
In the method for notifying an address, a query message for domain information of the second device is received from the first device, and a query message for domain information of the second device is used using the first version of the IP protocol. Transmitting the domain information of the second device to the server that manages the domain information of the second device, and not receiving a message that responds to the domain information of the second device.
Is transmitted to the server that manages the domain information of the device using the version of the IP protocol, and when a message that responds to the domain information of the second device is received, the second device of the second device included in the response message is received. Converting the IP address of the second version to the IP address of the first version, and transmitting a message notifying the IP address of the first version as the IP address of the second device to the first device. Characteristic notification method. 20. A first device that uses a first version of the IP protocol as a communication protocol is provided with an IP address of a second device that uses a second version of the IP protocol.
In the method of notifying an address, a query message for domain information of the second device is received from the first device, and a query message for domain information of the second device is used using the first version of the IP protocol. Transmitting the domain information of the device to the first server which manages the domain information, and not receiving a message responding to the domain information of the second device from the first server within a predetermined time; A domain information inquiry message is transmitted to a second server that manages domain information of a device using the second version of the IP protocol, and the second server sends the second information to the second server.
When receiving a message that responds to the domain information of the second device, the IP address of the second version of the second device included in the response message is set to the corresponding first address.
And transmitting a message notifying the IP address of the first version as the IP address of the second device to the first device. .