CN118827824A - IPv6 network access method, device and storage medium - Google Patents

Abstract

The embodiment of the present application provides an access method, device and storage medium for an IPv6 network, wherein, in the method, when the first IPv6 address corresponding to the first domain name is of the first type, the user-side device only needs to maintain a stateless corresponding table entry based on the first IPv4 address corresponding to the first domain name, and does not need to maintain a complex stateful NAT46 session table, thereby saving resources of the user-side device. In addition, the first IPv4 address in the above-mentioned stateless corresponding table entry is an existing IPv4 address corresponding to the first domain name, and does not need to occupy an IPv4 address in the user-side device address pool, thereby reducing IPv4 address consumption. In addition, the embodiment of the present application provides the real IPv4 address corresponding to the first domain name to the first terminal, which is conducive to the subsequent first terminal accessing the service through the real IPv4 address.

Description

IPv6 network access method, device and storage medium

Technical Field

The present application relates to the field of data communication technology, and in particular to an access method, device and storage medium of an IPv6 network.

Background Art

In recent years, with the continuous advancement of IPv6 transformation and the continuous evolution of new IPv6 technologies, global IPv6 traffic has increased significantly, especially in China. As the proportion of IPv6 traffic continues to increase, IPv6 single stack technology is also constantly evolving.

In the process of IPv6 single stack evolution, the scenario of Network Address Translation (NAT) conversion has received more and more attention. Among them, NAT64 means converting IPv6 addresses into IPv4 addresses, and NAT46 means converting IPv4 addresses into IPv6 addresses. In some scenarios, the network and service server sides have been upgraded to IPv6 single stack, but the terminal side may have a situation such as the home wireless router does not support IPv6, which may result in the home terminal only being assigned an IPv4 private address. In this case, the user side equipment (Customer Premise Equipment, CPE), such as the home gateway, needs to perform NAT46 conversion to complete the access to the IPv6 network and services.

In some NAT46 scenarios, the CPE needs to use the IPv4 in the locally configured IP address pool for address translation, resulting in the consumption of IPv4 addresses. In addition, it is necessary to maintain complex stateful NAT46 session entries, resulting in a waste of CPE resources.

Summary of the invention

At least one embodiment of the present application provides an IPv6 network access method, device, and storage medium for reducing the consumption of IPv4 addresses caused by network address translation and saving CPE resources.

In order to solve the above technical problems, this application is implemented as follows:

In a first aspect, an embodiment of the present application provides a method for accessing an IPv6 network, which is applied to a user-side device, including:

Receive a first request message sent by a first terminal, where the first request message is used to request an IPv4 address corresponding to a first domain name;

Sending a second request message to the domain name resolution server, where the second request message is used to request the IPv6 address corresponding to the first domain name;

Receive a first response message sent by the domain name resolution server, the first response message including a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type represented by a first IPv6 address prefix of a network address translation gateway and a first IPv4 address corresponding to the first domain name; a second type represented by an independent IPv6 address corresponding to the first domain name;

In the case where the first IPv6 address is of the first type, a stateless correspondence table entry between the first IPv6 address prefix and the first IPv4 address is generated, and the first IPv4 address corresponding to the first domain name is sent to the first terminal.

Optionally, the above method further includes:

receiving a first access request, wherein the destination address of the first access request is the first IPv4 address;

Performing a first address conversion process on the first access request and sending the processed first access request, wherein the first address conversion process includes:

According to the stateless correspondence table entry, the destination address of the first access request is converted into a first IPv6 address jointly represented by the first IPv6 address prefix and the first IPv4 address.

Optionally, the source address of the first access request is a second IPv4 address, and the first address conversion process further includes:

The source address of the first access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the above method further includes:

When the first IPv6 address is of the second type, a stateful correspondence table entry between the third IPv4 address and the first IPv6 address is generated according to the third IPv4 address in the IPv4 address pool, and the third IPv4 address corresponding to the first domain name is sent to the first terminal.

Optionally, the above method further includes:

receiving a second access request, wherein the destination address of the second access request is the third IPv4 address;

Performing a second address conversion process on the second access request and sending the processed second access request, wherein the second address conversion process includes:

According to the stateful corresponding table entry, the destination address of the second access request is converted into the first IPv6 address corresponding to the third IPv4 address.

Optionally, the source address of the second access request is a second IPv4 address, and the second address conversion process further includes:

The source address of the second access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the first response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

In a second aspect, an embodiment of the present application provides an IPv6 network access method, which is applied to a domain name resolution server, including:

Receive a request message sent by a user-side device, where the request message is used to request an IPv6 address corresponding to a first domain name;

Sending a response message to the user-side device, where the response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address;

Among them, the types of the first IPv6 address include: a first type represented by the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

Optionally, the response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

Optionally, before sending the response message to the user-side device, the method further includes:

Query the pre-established correspondence between the domain name, the IPv6 address, and the type of the IPv6 address to determine the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

In a third aspect, an embodiment of the present application provides a user side device, including a transceiver and a processor, wherein:

The transceiver is configured to receive a first request message sent by a first terminal, wherein the first request message is used to request an IPv4 address corresponding to a first domain name; send a second request message to a domain name resolution server, wherein the second request message is used to request an IPv6 address corresponding to the first domain name; receive a first response message sent by the domain name resolution server, wherein the first response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type jointly represented by a first IPv6 address prefix of a network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name;

The processor is configured to generate a stateless correspondence table entry between the first IPv6 address prefix and the first IPv4 address when the first IPv6 address is of the first type, and send the first IPv4 address corresponding to the first domain name to the first terminal.

Optionally, the transceiver is further used to receive a first access request, where the destination address of the first access request is the first IPv4 address;

The processor is further configured to perform a first address conversion process on the first access request and send the processed first access request, wherein the first address conversion process includes:

According to the stateless correspondence table entry, the destination address of the first access request is converted into a first IPv6 address jointly represented by the first IPv6 address prefix and the first IPv4 address.

Optionally, the source address of the first access request is a second IPv4 address, and the first address conversion process further includes:

The source address of the first access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the processor is also used to generate a stateful correspondence table entry between the third IPv4 address and the first IPv6 address according to a third IPv4 address in the IPv4 address pool when the first IPv6 address is of the second type, and send the third IPv4 address corresponding to the first domain name to the first terminal.

Optionally, the transceiver is further used to receive a second access request, the destination address of the second access request being the third IPv4 address;

The processor is further configured to perform a second address conversion process on the second access request, and send the processed second access request, wherein the second address conversion process includes:

According to the stateful corresponding table entry, the destination address of the second access request is converted into the first IPv6 address corresponding to the third IPv4 address.

Optionally, the source address of the second access request is a second IPv4 address, and the second address conversion process further includes:

The source address of the second access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the first response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

In a fourth aspect, an embodiment of the present application provides a user-side device, comprising: a processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the method described in the first aspect.

In a fifth aspect, an embodiment of the present application provides a domain name resolution server, including a transceiver and a processor, wherein:

The transceiver is used to receive a request message sent by a user-side device, where the request message is used to request an IPv6 address corresponding to the first domain name;

Sending a response message to the user-side device, where the response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address;

Among them, the types of the first IPv6 address include: a first type represented by the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

Optionally, the response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

Optionally, the processor is used to query the correspondence between the pre-established domain name, IPv6 address, and IPv6 address type before sending a response message to the user-side device, and determine the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

In a sixth aspect, an embodiment of the present application provides a domain name resolution server, comprising: a processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the method described in the second aspect.

In a seventh aspect, an embodiment of the present application provides a computer-readable storage medium, on which a program is stored. When the program is executed by a processor, the steps of the method described above are implemented.

Compared with the prior art, the access method, device and storage medium of the IPv6 network provided by the embodiment of the present application, when the first IPv6 address is of the first type, the user-side device only needs to maintain a stateless corresponding table item based on the real IPv4 address (first IPv4 address) corresponding to the first domain name, and does not need to maintain a complex stateful NAT46 session table, thereby saving resources (such as storage resources and computing resources) of the user-side device. In addition, the first IPv4 address in the above-mentioned stateless corresponding table item is an existing IPv4 address corresponding to the first domain name, and does not need to occupy the IPv4 address in the local address pool of the user-side device, thereby reducing IPv4 address consumption. In addition, the embodiment of the present application provides the real IPv4 address corresponding to the first domain name to the first terminal, which is conducive to the subsequent first terminal to access the service through the real IPv4 address.

BRIEF DESCRIPTION OF THE DRAWINGS

Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

FIG1 is a schematic diagram of a CPE performing NAT46 conversion in the related art;

FIG. 2 is another schematic diagram of CPE performing NAT46 conversion in the related art;

FIG3 is another schematic diagram of CPE performing NAT46 conversion in the related art;

FIG4 is a flow chart of a method for accessing an IPv6 network according to an embodiment of the present application;

FIG5 is another flow chart of a method for accessing an IPv6 network according to an embodiment of the present application;

6 is an example diagram of the interaction process between devices of the method for accessing an IPv6 network according to an embodiment of the present application;

7 is another example diagram of the interaction process between devices of the IPv6 network access method according to an embodiment of the present application;

FIG8 is an example diagram of an EDNS extension method according to an embodiment of the present application;

FIG9 is another example diagram of an EDNS extension method according to an embodiment of the present application;

FIG10 is a schematic diagram of the structure of a user-side device according to an embodiment of the present application;

FIG11 is a schematic diagram of the structure of a user-side device according to another embodiment of the present application;

FIG12 is a schematic diagram of the structure of a domain name resolution server according to an embodiment of the present application;

FIG13 is a schematic diagram of the structure of a domain name resolution server according to another embodiment of the present application;

FIG14 is a schematic diagram of the structure of a user-side device according to another embodiment of the present application;

FIG15 is a schematic diagram of the structure of a domain name resolution server according to another embodiment of the present application.

DETAILED DESCRIPTION

The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable in appropriate circumstances, so that the embodiments of the present application described herein can be implemented in a sequence other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, the process, method, system, product or equipment comprising a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment. "And/or" in the specification and claims represents at least one of the connected objects.

The following description provides examples and does not limit the scope, applicability, or configuration set forth in the claims. Changes may be made to the functions and arrangements of the elements discussed without departing from the spirit and scope of the present disclosure. Various examples may appropriately omit, replace, or add various procedures or components. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

When the network and service server sides have been upgraded to IPv6 single stack, and the terminal side can only be assigned IPv4 private addresses due to reasons such as the home wireless router not supporting IPv6, the CPE needs to perform NAT46 conversion to complete the access to IPv6 network and services. Please refer to Figures 1 and 2, the main processing is as follows:

Because the wireless router of the home network may not support IPv6, the home terminal can only be assigned an IPv4 private address. The laptops, mobile terminals and other terminals in Figure 1 are only assigned IPv4 private addresses. When these IPv4 terminals access IPv6 services, a NAT46 conversion needs to be completed on the CPE, including NAT46 conversion of the source address and NAT46 conversion of the destination address.

Among them, for NAT46 conversion of source address: the IPv6 source address can be directly generated by adding the IPv4 private address to the LAN side IPv6 prefix previously obtained by the CPE. This is a stateless NAT46 conversion technology. For NAT46 conversion of destination address, it can be achieved through stateful NAT46 technology.

In addition, in the fixed network scenario, NAT46 can be deployed on the home gateway CPE; in the mobile scenario, NAT46 can be deployed on the terminal. The embodiment of this application mainly takes the fixed network scenario as an example for explanation, and the implementation in the mobile scenario is similar to the fixed network scenario. This application is applicable to both fixed network and mobile scenarios.

The service flow of the related technical solution is shown in FIG2 . From the perspective of the terminal accessing the IPv6 service server 1 (the return direction can be converted in the opposite direction), it includes:

(1) The terminal initiates a DNS4 query request to request the IPv4 address corresponding to the domain name of service server 1 (e.g., www.abc.com). After receiving the request, the CPE acts as a DNS proxy to initiate a DNS6 query request to request the IPv6 address corresponding to the domain name from the DNS server.

(2) After receiving the AAAA record (including the IPv6 address of service server 1) returned by the DNS Server, the CPE performs stateful NAT46 translation, that is, based on the previously configured IPv4 address pool, generates and saves a NAT46 translation table entry for service server 1, such as service server 1-IPv4 address <-> service server 1-IPv6 address.

(3) The CPE sends the converted IPv4 address of the service server 1 (service server 1-IPv4 address) to the terminal via a DNS4 response message.

(4) The terminal uses this address as the destination address to initiate an IPv4 access request. After the access request reaches the CPE, NAT46 conversion is performed:

Stateless NAT46 translation of the source address: The source IPv4 address of the access request is translated from the IPv4 private address to the source IPv6 address represented by the combination of the IPv4 private address and the LAN-side IPv6 prefix of the CPE.

Stateful NAT46 conversion of the destination address: Use the previous stateful NAT46 conversion table entry for conversion, that is, convert the destination IPv4 address of the access request from the service server 1-IPv4 address to the service server 1-IPv6 address.

As shown in FIG. 3 , in the NAT46 scenario, there are some Internet Content Providers (ICPs). Their service servers that provide content are still IPv4 servers, but they provide IPv6-like services to the outside world by deploying NAT64 gateways.

In this case, the AAAA record (IPv6 address) returned to the user by the DNS server of the ICP is: the IPv6 address represented by the IPv6 prefix of the NAT64 gateway and the IPv4 service server 1-IPv4 address 1, that is, the IPv6 prefix of the NAT64 gateway + IPv4 service server 1-IPv4 address 1. However, the IPv6 address needs to be converted by stateful NAT46 in the CPE, and the converted address is: IPv4 service server 1-IPv4 address 2. Then there will be the following problems:

1) IPv4 service server 1 consumes IPv4 address 1 and IPv4 address 2, thus resulting in more IPv4 address consumption;

2) It is necessary to maintain a complex stateful NAT46 session table, which results in a waste of CPE resources;

3) In addition, the real IPv4 address (such as IPv4 service server 1-IPv4 address 1) corresponding to the domain name is not sent to the client, which is not conducive to business development.

In order to solve at least one of the above problems, the embodiment of the present application provides an access method for an IPv6 network, which can reduce the consumption of IPv4 addresses caused by network address translation and save CPE resources. Referring to FIG. 4 , the access method for an IPv6 network provided in the embodiment of the present application, when applied to a user-side device such as a CPE, includes:

Step 41: Receive a first request message sent by a first terminal, where the first request message is used to request an IPv4 address corresponding to a first domain name.

Here, the first request message may be a DNS4 query request, which includes the first domain name and type A (type: A) to request the IPv4 address corresponding to the first domain name.

Step 42: Send a second request message to the domain name resolution server, where the second request message is used to request the IPv6 address corresponding to the first domain name.

Here, the second request message may be a DNS query request, which includes the first domain name and type 4A (type: AAAA) to request the IPv6 address corresponding to the first domain name.

Step 43, receiving a first response message sent by the domain name resolution server, the first response message including a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type represented by a first IPv6 address prefix of a network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

Here, the first response message may be a DNS response message based on the Extension Mechanisms for DNS (EDNS) protocol, and the type of the first IPv6 address is carried in a reserved field (Z field) in the OPT resource record of the DNS response message, or carried in a reserved field (Z field) in the header portion of the DNS response message. The first IPv6 address of the first type is an IPv6 address formed by concatenating the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name. The first IPv6 address of the second type is an IPv6 address assigned to the first domain name, and at this time, the first domain name may not have an assigned IPv4 address. The independent IPv6 address means that the IPv6 address is assigned to the first domain name as a whole, rather than being concatenated by the IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name.

In this way, by parsing the first response message, the user-side device can obtain the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

Step 44: When the first IPv6 address is of the first type, generate a stateless correspondence table entry between the first IPv6 address prefix and the first IPv4 address, and send the first IPv4 address corresponding to the first domain name to the first terminal.

Here, when the first IPv6 address is of the first type, the user side device generates a stateless correspondence table entry, in which the correspondence between the first IPv6 address prefix and the first IPv4 address is maintained. In addition, the user side device also sends the first IPv4 address corresponding to the first domain name to the first terminal.

Through the above steps, in the embodiment of the present application, when the first IPv6 address is of the first type, the user-side device only needs to maintain a stateless corresponding table item based on the real IPv4 address (first IPv4 address) corresponding to the first domain name, and does not need to maintain a complex stateful NAT46 session table, thereby saving resources (such as storage resources and computing resources) of the user-side device. In addition, the first IPv4 address in the above-mentioned stateless corresponding table item is an existing IPv4 address corresponding to the first domain name, and does not need to occupy the IPv4 address in the local address pool of the user-side device, thereby reducing IPv4 address consumption. In addition, since in step 44, the embodiment of the present application provides the real IPv4 address corresponding to the first domain name to the first terminal, this is conducive to the subsequent first terminal to access the service through the real IPv4 address.

After obtaining the real IPv4 address corresponding to the first domain name, the first terminal may initiate access to related services based on the real IPv4 address, for example, initiating an IPv4 access request on the data plane (assuming it is a first access request). At this time, the above method further includes:

Step 45a: The user-side device receives a first access request, where the destination address of the first access request is the first IPv4 address.

Here, the source address of the first access request is the IPv4 address of the first terminal itself (assuming it is the second IPv4 address, such as IPv4 private network address 1), and the destination address is the first IPv4 address.

Step 46a, the user-side device performs a first address conversion process on the first access request and sends the processed first access request, wherein the first address conversion process includes: according to the stateless corresponding table entry, converting the destination address of the first access request into a first IPv6 address jointly represented by the first IPv6 address prefix and the first IPv4 address.

Here, the first address conversion process is a NAT46 conversion process. In addition, in step 46a, the first address conversion process may also include: converting the source address of the first access request to a second IPv6 address represented by the second IPv6 address prefix of the user-side device and the second IPv4 address. That is, the second IPv6 address is an IPv6 address formed by concatenating the second IPv6 address prefix of the user-side device and the second IPv4 address.

In an embodiment of the present application, when the first IPv6 address obtained in the above step 43 is of the second type, the user-side device can generate a stateful correspondence table entry between the third IPv4 address and the first IPv6 address based on the third IPv4 address in the IPv4 address pool (such as the address pool configured by the user-side device itself), and send the third IPv4 address corresponding to the first domain name to the first terminal.

Similarly, after obtaining the third IPv4 address corresponding to the first domain name, the first terminal may initiate access to related services based on the third IPv4 address, for example, initiating an IPv4 access request on the data plane (assuming it is a second access request). At this time, the method further includes:

Step 45b: The user-side device receives a second access request, where the destination address of the second access request is the third IPv4 address.

Here, the source address of the second access request is the IPv4 address of the first terminal itself (assuming it is the second IPv4 address, such as IPv4 private network address 1), and the destination address is the third IPv4 address.

Step 46b, the user-side device performs a second address conversion process on the second access request and sends the processed second access request, wherein the second address conversion process includes: according to the stateful corresponding table entry, converting the destination address of the second access request into the first IPv6 address corresponding to the third IPv4 address.

Here, the second address conversion process is a NAT46 conversion process. In addition, in step 46b, the second address conversion process may also include: converting the source address of the second access request to a second IPv6 address represented by the second IPv6 address prefix of the user-side device and the second IPv4 address. That is, the second IPv6 address is an IPv6 address formed by concatenating the second IPv6 address prefix of the user-side device and the second IPv4 address.

Referring to FIG. 5 , the IPv6 network access method provided in the embodiment of the present application, when applied to a domain name resolution server, includes:

Step 51: Receive a request message sent by a user-side device, where the request message is used to request an IPv6 address corresponding to a first domain name.

Here, the request message may be a DNS query request, which includes the first domain name and type 4A (type: AAAA) to request the IPv6 address corresponding to the first domain name.

Step 52, sending a response message to the user side device, the response message including the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type represented by the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name; a second type represented by an independent IPv6 address corresponding to the first domain name.

Here, the response message may be a DNS response message based on the EDNS protocol, and the type of the first IPv6 address is carried in a reserved field (Z field) in the OPT resource record of the DNS response message, or carried in a reserved field (Z field) in the header portion of the DNS response message. The first IPv6 address of the first type is an IPv6 address formed by concatenating the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name. The first IPv6 address of the second type is an IPv6 address assigned to the first domain name.

Specifically, the domain name resolution server can determine the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address by querying the pre-established correspondence between the domain name, IPv6 address, and the type of the IPv6 address. The above correspondence can be pre-configured in the domain name resolution server.

Through the above steps, the domain name resolution server notifies the user-side device of the type of the first IPv6 address corresponding to the first domain name, so as to help the user-side device establish a stateless corresponding table entry when the first IPv6 address is of the first type, so as to save IPv4 resources and user-side device resources.

The above describes the relevant methods of the embodiments of the present application from the user side device and the domain name resolution server side. The following further describes the above methods of the embodiments of the present application by further combining Figures 6 and 7 through examples of the interaction process between devices. Among them, Figure 6 is an example of the process for the IPv6 address corresponding to the domain name as the first type, and Figure 7 is an example of the process for the IPv6 address corresponding to the domain name as the second type.

The following example solves the NAT46 related issues by extending the DNS protocol:

For the AAAA record returned by the DNS server, the CPE needs to distinguish whether the IPv6 service is provided directly through a pure IPv6 server (corresponding to the second type of IPv6 address) or through a "NAT64+IPv4 server" (corresponding to the first type of IPv6 address). For the former, stateful NAT46 is still used, while for the latter, stateless NAT46 can be used, which can reduce the waste of IPv4 addresses and the pressure on the CPE to maintain the NAT session table, while providing the real IPv4 server address to the terminal (client).

Specifically, by extending the DNS protocol, the DNS server identifies which IPv6 service mode the server of the AAAA record is (ie, the type of IPv6 address corresponding to the domain name) when returning the AAAA record through a DNS response message.

Extension method 1: EDNS extension

First, as shown in Figure 8, it is necessary to add a bit as a "NAT" identifier in the "Z" field (i.e., reserved field) in the OPT resource record of the DNS response message. When the bit is set to 1, it means "the IPv6 service provided by the AAAA record is: NAT64+IPv4 mode", that is, the domain name corresponds to the IPv6 address of the first type above; when the bit is set to 0, it means "the IPv6 service provided by the AAAA record is: pure IPv6 mode", that is, the domain name corresponds to the IPv6 address of the second type above.

After EDNS is extended, the process of the "NAT64+IPv4 server" IPv6 service mode (i.e., the domain name corresponding to the IPv6 address is the first type above) is shown in Figure 6, which mainly includes:

Step a: The terminal initiates a DNS4 query request to obtain the A record of a domain name (the IPv4 address corresponding to the requested domain name).

Step b: After receiving the query request, the CPE requests the AAAA record of the domain name (requesting the IPv6 address corresponding to the domain name) from the DNS Server.

Step c: The DNS Server returns the AAAA record of the domain name, and the "NAT" flag in the OPT resource record is set to 1. The IPv6 address included in the AAAA record is an IPv6 address formed by concatenating the NAT64 prefix and the IPv4 address 1 corresponding to the domain name.

Step d: Since the "NAT" bit is 1, the CPE performs stateless NAT46 conversion, that is, generates and saves a stateless correspondence table entry between the NAT64 prefix and the IPv4 address 1.

Step e: The CPE sends a DNS4 response to the terminal, returning the A record of the domain name (IPv4 address 1);

Step f: The terminal enables IPv4 data plane access: the source address is the terminal's IPv4 private address, and the destination address is IPv4 address 1.

Step g: CPE performs NAT46 translation. The translation of source address and destination address are both stateless NAT46 translation:

The source address is converted to: CPE LAN side IPv6 prefix + IPv4 private address;

The destination address is converted to: NAT64 prefix + IPv4 address 1.

Step h: After NAT46 conversion is completed, enable IPv6 data plane access.

After EDNS is extended, the process of the "pure IPv6 server" IPv6 service mode (i.e., the domain name corresponding to the IPv6 address is the second type above) is shown in Figure 7, including:

Step a: The terminal initiates a DNS4 query request to obtain the A record of a domain name (the IPv4 address corresponding to the requested domain name).

Step b: After receiving the query request, the CPE requests the AAAA record of the domain name (the IPv6 address corresponding to the requested domain name) from the DNS Server.

Step c: The DNS Server returns the AAAA record of the domain name, and the "NAT" flag in the OPT resource record is set to 0. At this time, the IPv6 address included in the AAAA record is the independent IPv6 address corresponding to the domain name.

Step d: Since the "NAT" bit is 0, the CPE performs stateful NAT46 translation, that is, generates and saves a stateful NAT46 entry according to the configured IPv4 address pool: IPv4 address 1 in the IPv4 address pool <-> IPv6 address 1 in the AAAA record.

Step e: The CPE sends a DNS4 response to the terminal, returning the A record of the domain name (IPv4 address 1 in the IPv4 address pool).

Step f: The terminal enables IPv4 data plane access: the source address is an IPv4 private address, and the destination address is IPv4 address 1 in the IPv4 address pool.

Step g: CPE performs NAT46 translation, where the source address is stateless NAT46 translation and the destination address is stateful NAT46 translation:

The source address is converted to: CPE LAN side IPv6 prefix + IPv4 private address;

The destination address is converted to: IPv6 address 1 in the AAAA record.

Step 8: After NAT46 conversion is completed, enable IPv6 data plane access.

As another extension method of EDNS extension, as shown in Figure 9, for the Header part of the DNS response message, one bit of the original three reserved bits (Z field) can be used as the "NAT" identifier. When the bit is set to 1, it means "the IPv6 service provided by the AAAA record is: NAT64+IPv4 mode", that is, the domain name corresponds to the IPv6 address of the first type above; when the bit is set to 0, it means "the IPv6 service provided by the AAAA record is: pure IPv6 mode", that is, the domain name corresponds to the IPv6 address of the second type above.

After the header is expanded, the processes of the two IPv6 service modes are similar to Figure 6 and Figure 7 respectively. The only difference is the location of the "NAT" flag.

The above describes various methods of the embodiments of the present application. The following further provides devices for implementing the above methods.

Referring to FIG. 10 , the present embodiment further provides a user-side device, including:

A first receiving module 1001 is used to receive a first request message sent by a first terminal, where the first request message is used to request an IPv4 address corresponding to a first domain name;

A first sending module 1002 is used to send a second request message to a domain name resolution server, where the second request message is used to request an IPv6 address corresponding to the first domain name;

The second receiving module 1003 is used to receive a first response message sent by the domain name resolution server, wherein the first response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type represented by a first IPv6 address prefix of a network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name;

The first processing module 1004 is used to generate a stateless correspondence table entry between the first IPv6 address prefix and the first IPv4 address when the first IPv6 address is of the first type, and send the first IPv4 address corresponding to the first domain name to the first terminal.

Through the above modules, the embodiment of the present application can reduce the consumption of IPv4 addresses caused by network address translation and save CPE resources.

Optionally, the user-side device further includes:

A third receiving module, configured to receive a first access request, wherein the destination address of the first access request is the first IPv4 address;

The second processing module is configured to perform a first address conversion process on the first access request and send the processed first access request, wherein the first address conversion process includes:

According to the stateless correspondence table entry, the destination address of the first access request is converted into a first IPv6 address jointly represented by the first IPv6 address prefix and the first IPv4 address.

Optionally, the source address of the first access request is a second IPv4 address, and the first address conversion process further includes:

The source address of the first access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the user-side device further includes:

The third processing module is used to generate a stateful correspondence table entry between the third IPv4 address and the first IPv6 address according to the third IPv4 address in the IPv4 address pool when the first IPv6 address is of the second type, and send the third IPv4 address corresponding to the first domain name to the first terminal.

Optionally, the user-side device further includes:

a fourth receiving module, configured to receive a second access request, wherein the destination address of the second access request is the third IPv4 address;

The fourth processing module is configured to perform a second address conversion process on the second access request and send the processed second access request, wherein the second address conversion process includes:

According to the stateful corresponding table entry, the destination address of the second access request is converted into the first IPv6 address corresponding to the third IPv4 address.

Optionally, the source address of the second access request is a second IPv4 address, and the second address conversion process further includes:

The source address of the second access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the first response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

It should be noted that the device in this embodiment is a device corresponding to the method applied to the user-side device, and the implementation methods in the above embodiments are all applicable to the embodiments of the device, and can also achieve the same technical effect. The above device provided in the embodiment of the present application can implement all the method steps implemented in the above method embodiment, and can achieve the same technical effect. The parts and beneficial effects that are the same as those in the method embodiment in this embodiment will not be specifically described here.

Please refer to FIG11 , an embodiment of the present application further provides a terminal 1100 , including: a transceiver 1101 and a processor 1102 ;

The transceiver 1101 is configured to receive a first request message sent by a first terminal, wherein the first request message is used to request an IPv4 address corresponding to a first domain name; send a second request message to a domain name resolution server, wherein the second request message is used to request an IPv6 address corresponding to the first domain name; receive a first response message sent by the domain name resolution server, wherein the first response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address; wherein the type of the first IPv6 address includes: a first type jointly represented by a first IPv6 address prefix of a network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name;

The processor 1102 is configured to generate a stateless correspondence table entry between the first IPv6 address prefix and the first IPv4 address when the first IPv6 address is of the first type, and send the first IPv4 address corresponding to the first domain name to the first terminal.

Optionally, the transceiver is further used to receive a first access request, where the destination address of the first access request is the first IPv4 address;

The processor is further configured to perform a first address conversion process on the first access request and send the processed first access request, wherein the first address conversion process includes:

According to the stateless correspondence table entry, the destination address of the first access request is converted into a first IPv6 address jointly represented by the first IPv6 address prefix and the first IPv4 address.

Optionally, the source address of the first access request is a second IPv4 address, and the first address conversion process further includes:

The source address of the first access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the processor is also used to generate a stateful correspondence table entry between the third IPv4 address and the first IPv6 address according to a third IPv4 address in the IPv4 address pool when the first IPv6 address is of the second type, and send the third IPv4 address corresponding to the first domain name to the first terminal.

Optionally, the transceiver is further used to receive a second access request, the destination address of the second access request being the third IPv4 address;

The processor is further configured to perform a second address conversion process on the second access request, and send the processed second access request, wherein the second address conversion process includes:

According to the stateful corresponding table entry, the destination address of the second access request is converted into the first IPv6 address corresponding to the third IPv4 address.

Optionally, the source address of the second access request is a second IPv4 address, and the second address conversion process further includes:

The source address of the second access request is converted into a second IPv6 address represented by a combination of a second IPv6 address prefix of the user-side device and the second IPv4 address.

Optionally, the first response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

It should be noted that the device in this embodiment is a device corresponding to the method applied to the user-side device, and the implementation methods in the above embodiments are all applicable to the embodiments of the device, and can also achieve the same technical effect. The above device provided in the embodiment of the present application can implement all the method steps implemented in the above method embodiment, and can achieve the same technical effect. The parts and beneficial effects that are the same as those in the method embodiment in this embodiment will not be specifically described here.

Referring to FIG. 12 , the embodiment of the present application further provides a domain name resolution server, including:

A first receiving module 1201 is used for a request message sent by a device, where the request message is used to request an IPv6 address corresponding to a first domain name;

A first sending module 1202 is configured to send a response message to the user-side device, where the response message includes a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address;

Among them, the types of the first IPv6 address include: a first type represented by the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

Through the above modules, the embodiment of the present application reduces the consumption of IPv4 addresses caused by network address translation and saves CPE resources.

Optionally, the response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

Optionally, the domain name resolution server further includes:

The query module is used to query the pre-established correspondence between the domain name, IPv6 address, and the type of IPv6 address, and determine the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

It should be noted that the device in this embodiment is a device corresponding to the method applied to the domain name resolution server side, and the implementation methods in the above embodiments are all applicable to the embodiments of the device, and can also achieve the same technical effects. The above device provided in the embodiment of the present application can implement all the method steps implemented in the above method embodiment, and can achieve the same technical effects. The parts and beneficial effects that are the same as those in the method embodiment in this embodiment will not be specifically described here.

Please refer to FIG. 13 , the embodiment of the present application further provides a domain name resolution server 1300 , including: a transceiver 1301 and a processor 1302 ;

The transceiver 1301 is configured to receive a request message sent by a user-side device, the request message being used to request an IPv6 address corresponding to a first domain name; and send a response message to the user-side device, the response message including a first IPv6 address corresponding to the first domain name and a type of the first IPv6 address;

Among them, the types of the first IPv6 address include: a first type represented by the first IPv6 address prefix of the network address translation gateway and the first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

Optionally, the response message is a DNS response message based on the domain name resolution extended EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in the OPT resource record of the DNS response message, or in a reserved field in the header part of the DNS response message.

Optionally, the processor is used to query the pre-established correspondence between the domain name, IPv6 address, and IPv6 address type before sending a response message to the user-side device, and determine the first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

It should be noted that the device in this embodiment is a device corresponding to the method applied to the domain name resolution server side, and the implementation methods in the above embodiments are all applicable to the embodiments of the device, and can also achieve the same technical effects. The above device provided in the embodiment of the present application can implement all the method steps implemented in the above method embodiment, and can achieve the same technical effects. The parts and beneficial effects that are the same as those in the method embodiment in this embodiment will not be specifically described here.

Please refer to Figure 14. An embodiment of the present application also provides a user-side device 1400, including a processor 1401, a memory 1402, and a computer program stored in the memory 1402 and executable on the processor 1401. When the computer program is executed by the processor 1401, each process of the above-mentioned IPv6 network access method embodiment executed by the user-side device is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

Please refer to Figure 15. An embodiment of the present application also provides a domain name resolution server 1500, including a processor 1501, a memory 1502, and a computer program stored in the memory 1502 and executable on the processor 1501. When the computer program is executed by the processor 1501, each process of the above-mentioned IPv6 network access method embodiment executed by the domain name resolution server is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

The embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, each process of the above-mentioned IPv6 network access method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it is not repeated here. The computer-readable storage medium is, for example, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

It should be noted that, in this article, the terms "include", "include" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims (23)

1. An access method of an IPv6 network, applied to a user side device, is characterized by comprising:

Receiving a first request message sent by a first terminal, wherein the first request message is used for requesting an IPv4 address corresponding to a first domain name;

Sending a second request message to a domain name resolution server, wherein the second request message is used for requesting an IPv6 address corresponding to the first domain name;

Receiving a first response message sent by the domain name resolution server, wherein the first response message comprises a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address; wherein, the types of the first IPv6 address include: a first type jointly represented by a first IPv6 address prefix of the network address translation gateway and a first IPv4 address corresponding to the first domain name; a second type represented by an independent IPv6 address corresponding to the first domain name;

And under the condition that the first IPv6 address is of the first type, generating a stateless corresponding table entry of the first IPv6 address prefix and the first IPv4 address, and sending the first IPv4 address corresponding to the first domain name to the first terminal.

2. The method as recited in claim 1, further comprising:

receiving a first access request, wherein the destination address of the first access request is the first IPv4 address;

performing first address conversion processing on the first access request, and sending the processed first access request, wherein the first address conversion processing comprises:

And converting the destination address of the first access request into a first IPv6 address which is jointly represented by the first IPv6 address prefix and the first IPv4 address according to the stateless corresponding table entry.

3. The method of claim 2, wherein the source address of the first access request is a second IPv4 address, and wherein the first address translation process further comprises:

and converting the source address of the first access request into a second IPv6 address which is jointly represented by a second IPv6 address prefix of the user side device and the second IPv4 address.

4. A method according to any one of claims 1 to 3, further comprising:

And under the condition that the first IPv6 address is of the second type, generating a stateful corresponding table entry of the third IPv4 address and the first IPv6 address according to the third IPv4 address in the IPv4 address pool, and sending the third IPv4 address corresponding to the first domain name to the first terminal.

5. The method as recited in claim 4, further comprising:

Receiving a second access request, wherein the destination address of the second access request is the third IPv4 address;

performing second address conversion processing on the second access request, and sending the processed second access request, wherein the second address conversion processing includes:

and converting the destination address of the second access request into the first IPv6 address corresponding to the third IPv4 address according to the stateful corresponding table entry.

6. The method of claim 5, wherein the source address of the second access request is a second IPv4 address, and wherein the second address translation process further comprises:

And converting the source address of the second access request into a second IPv6 address which is jointly represented by a second IPv6 address prefix of the user side device and the second IPv4 address.

7. The method of claim 1, wherein the step of determining the position of the substrate comprises,

The first response message is a DNS response message based on the domain name resolution extension EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in an OPT resource record of the DNS response message or in a reserved field of a Header portion of the DNS response message.

8. An access method of an IPv6 network, applied to a domain name resolution server, is characterized by comprising:

receiving a request message sent by user side equipment, wherein the request message is used for requesting an IPv6 address corresponding to a first domain name;

Transmitting a response message to the user side equipment, wherein the response message comprises a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address;

Wherein, the types of the first IPv6 address include: a first type jointly represented by a first IPv6 address prefix of the network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

9. The method of claim 8, wherein the step of determining the position of the first electrode is performed,

The response message is a DNS response message based on the domain name resolution extension EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in an OPT resource record of the DNS response message or in a reserved field of a Header portion of the DNS response message.

10. The method of claim 8, wherein prior to sending a response message to the user-side device, the method further comprises:

Inquiring a pre-established corresponding relation among the domain name, the IPv6 address and the type of the IPv6 address, and determining a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

11. A user side device comprising a transceiver and a processor, wherein,

The transceiver is configured to receive a first request message sent by a first terminal, where the first request message is used to request an IPv4 address corresponding to a first domain name; sending a second request message to a domain name resolution server, wherein the second request message is used for requesting an IPv6 address corresponding to the first domain name; receiving a first response message sent by the domain name resolution server, wherein the first response message comprises a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address; wherein, the types of the first IPv6 address include: a first type jointly represented by a first IPv6 address prefix of the network address translation gateway and a first IPv4 address corresponding to the first domain name; a second type represented by an independent IPv6 address corresponding to the first domain name;

The processor is configured to generate a stateless corresponding entry of the first IPv6 address prefix and the first IPv4 address, and send the first IPv4 address corresponding to the first domain name to the first terminal, where the first IPv6 address is of the first type.

12. The apparatus of claim 11, wherein the user side device,

The transceiver is further configured to receive a first access request, where a destination address of the first access request is the first IPv4 address;

the processor is further configured to perform a first address conversion process on the first access request, and send the processed first access request, where the first address conversion process includes:

And converting the destination address of the first access request into a first IPv6 address which is jointly represented by the first IPv6 address prefix and the first IPv4 address according to the stateless corresponding table entry.

13. The user side device of claim 12, wherein the source address of the first access request is a second IPv4 address, and wherein the first address translation process further comprises:

and converting the source address of the first access request into a second IPv6 address which is jointly represented by a second IPv6 address prefix of the user side device and the second IPv4 address.

14. The user side device according to any of the claims 11 to 13, characterized in that,

The processor is further configured to generate, when the first IPv6 address is of the second type, a stateful correspondence table entry between the third IPv4 address and the first IPv6 address according to a third IPv4 address in an IPv4 address pool, and send the third IPv4 address corresponding to the first domain name to the first terminal.

15. The apparatus of claim 14, wherein the user side device,

The transceiver is further configured to receive a second access request, where a destination address of the second access request is the third IPv4 address;

The processor is further configured to perform a second address conversion process on the second access request, and send the processed second access request, where the second address conversion process includes:

and converting the destination address of the second access request into the first IPv6 address corresponding to the third IPv4 address according to the stateful corresponding table entry.

16. The user side device of claim 15, wherein the source address of the second access request is a second IPv4 address, and wherein the second address translation process further comprises:

And converting the source address of the second access request into a second IPv6 address which is jointly represented by a second IPv6 address prefix of the user side device and the second IPv4 address.

17. The apparatus of claim 11, wherein the user side device,

The first response message is a DNS response message based on the domain name resolution extension EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in an OPT resource record of the DNS response message or in a reserved field of a Header portion of the DNS response message.

18. A user-side device, comprising: a processor, a memory and a program stored on the memory and executable on the processor, which when executed by the processor, performs the steps of the method according to any one of claims 1 to 7.

19. A domain name resolution server comprising a transceiver and a processor, wherein,

The transceiver is configured to receive a request message sent by a user side device, where the request message is used to request an IPv6 address corresponding to the first domain name;

Transmitting a response message to the user side equipment, wherein the response message comprises a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address;

Wherein, the types of the first IPv6 address include: a first type jointly represented by a first IPv6 address prefix of the network address translation gateway and a first IPv4 address corresponding to the first domain name; and a second type represented by an independent IPv6 address corresponding to the first domain name.

20. The domain name resolution server of claim 19, wherein the domain name resolution server is configured to,

The response message is a DNS response message based on the domain name resolution extension EDNS protocol, and the type of the first IPv6 address is carried in a reserved field in an OPT resource record of the DNS response message or in a reserved field of a Header portion of the DNS response message.

21. The domain name resolution server of claim 19, wherein the domain name resolution server is configured to,

The processor is configured to query a correspondence between a domain name, an IPv6 address, and a type of the IPv6 address, which are established in advance, before sending a response message to the user side device, and determine a first IPv6 address corresponding to the first domain name and the type of the first IPv6 address.

22. A domain name resolution server, comprising: a processor, a memory and a program stored on the memory and executable on the processor, which when executed by the processor performs the steps of the method according to any one of claims 8 to 10.

23. A computer-readable storage medium, on which a computer program is stored, which computer program, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 10.