A method and nat equipment for traversing two levels of nat

Abstract

The embodiment of the invention provides a method for traversing two-stage NAT (network address translation). The method comprises that a port allowing first-stage NAT equipment to traverse is determined when the first-stage NAT equipment receives a first traverse request message sent by a service provider located in a private network through an UPnP (universal plug and play) protocol; the first-stage NAT equipment sends a second traverse request message to second-stage NAT equipment connected with a service demand end in an external network through a PCP (port control protocol) so as to determine a port allowing the second-stage NAT equipment to traverse and enable the service demand end of the external network to be communicated with the service provider of the private network through the port allowing the first-stage NAT equipment to traverse and the port allowing the second-stage NAT equipment to traverse. The embodiment of the invention further provides NAT equipment. The technical solution provided by the embodiment of the invention avoids promotion of the technical complexity and increase of the additional cost brought about by carrying out transformation and upgrading on a lot of network equipment.

Description

technical field

[0001] The invention relates to the technical field of communication, in particular to a method for traversing two-level NAT and NAT equipment. Background technique

[0002] With the continuous development of network technology and the increasing variety of network application scenarios, the networking mode of the existing networking environment has gradually evolved from a single-level NAT (Network Address Translation) networking to a two-level NAT networking mode. Problems such as IPV4 (Internet Protocol V4, Internet Protocol Version 4) address exhaustion have been resolved.

[0003] In single-level networking mode (see attached Figure 1a ), the public network accesses the private network and the external network accesses the intranet, only needs to pass through the first-level NAT device, and in the two-level networking mode (see the attached Figure 1b ), you need to traverse two levels of NAT devices.

[0004] In the prior art, a UPnP (Universal Plug ...

Examples

Embodiment 1

[0021] See attached figure 2 , the figure shows an embodiment of a method for traversing two-level NAT provided by the present invention, that is, Embodiment 1. This embodiment is applied to a networking environment with two-level NAT devices. In this embodiment, the first-level NAT device is connected to the service provider of the private network to form a first-level NAT network. The first-level NAT device can simultaneously Connect with a plurality of other NAT devices respectively, wherein, every other NAT device can form a NAT network with this first level NAT device, in this embodiment, this NAT network can be understood as, a NAT device needs When converting the IP address in the data packet sent by another NAT device or service provider or service demand end, the local network formed, that is to say, the first-level NAT device can communicate with multiple other NAT devices at the same time. The device constitutes multiple NAT networks of the same level, wherein the...

Embodiment 2

[0056] The above-mentioned embodiments have introduced the technical solution of the present invention, but in order to understand the technical content of the present invention more clearly, a relatively simple two-level NAT device networking environment is taken as an example for illustration below. See attached image 3 As shown, the figure shows an application scenario of implementing NAT device traversal in a two-level NAT device networking environment, and this method constitutes the second embodiment of the present invention. In this embodiment, the first-level NAT device is a home gateway, which is connected to the PC of the home user, and the second-level NAT device is a CGN device (Carrier-grade NAT, operator-level NAT), and the CGN device is connected to the external Subjects are connected. The home user starts the WEB service application on the PC (service provider) in the private network, and the external host located in the external network (public network) acts...

Embodiment 3

[0063] The technical solution of the present invention will be described below with a specific example, which constitutes Embodiment 3 of the present invention, and this embodiment is applicable to the implementation of P2P protocol software in the network after the first-level NAT networking is upgraded to a two-level NAT networking. application.

[0064] At present, P2P software is widely used. Common downloading tools such as "BT" and "EDonkey" all belong to P2P software. An important feature of this type of software is its fast download speed. All user devices can provide "re-download" as a "server", that is to say, when a user downloads a file, it also provides other users to download from their own device. From the perspective of the user who is downloading, on the one hand, he is a "user" who downloads from many "servers" (each user device participating in the download can be regarded as a server); on the other hand, he is also another user. A "server" while downloadin...

technical field

[0001] The invention relates to the technical field of communication, in particular to a method for traversing two-level NAT and NAT equipment. Background technique

[0002] With the continuous development of network technology and the increasing variety of network application scenarios, the networking mode of the existing networking environment has gradually evolved from a single-level NAT (Network Address Translation) networking to a two-level NAT networking mode. Problems such as IPV4 (Internet Protocol V4, Internet Protocol Version 4) address exhaustion have been resolved.

[0003] In single-level networking mode (see attached Figure 1a ), the public network accesses the private network and the external network accesses the intranet, only needs to pass through the first-level NAT device, and in the two-level networking mode (see the attached Figure 1b ), you need to traverse two levels of NAT devices.

[0004] In the prior art, a UPnP (Universal Plug ...

Examples

Embodiment 1

[0021] See attached figure 2 , the figure shows an embodiment of a method for traversing two-level NAT provided by the present invention, that is, Embodiment 1. This embodiment is applied to a networking environment with two-level NAT devices. In this embodiment, the first-level NAT device is connected to the service provider of the private network to form a first-level NAT network. The first-level NAT device can simultaneously Connect with a plurality of other NAT devices respectively, wherein, every other NAT device can form a NAT network with this first level NAT device, in this embodiment, this NAT network can be understood as, a NAT device needs When converting the IP address in the data packet sent by another NAT device or service provider or service demand end, the local network formed, that is to say, the first-level NAT device can communicate with multiple other NAT devices at the same time. The device constitutes multiple NAT networks of the same level, wherein the...

Embodiment 2

[0056] The above-mentioned embodiments have introduced the technical solution of the present invention, but in order to understand the technical content of the present invention more clearly, a relatively simple two-level NAT device networking environment is taken as an example for illustration below. See attached image 3 As shown, the figure shows an application scenario of implementing NAT device traversal in a two-level NAT device networking environment, and this method constitutes the second embodiment of the present invention. In this embodiment, the first-level NAT device is a home gateway, which is connected to the PC of the home user, and the second-level NAT device is a CGN device (Carrier-grade NAT, operator-level NAT), and the CGN device is connected to the external Subjects are connected. The home user starts the WEB service application on the PC (service provider) in the private network, and the external host located in the external network (public network) acts...

Embodiment 3

[0063] The technical solution of the present invention will be described below with a specific example, which constitutes Embodiment 3 of the present invention, and this embodiment is applicable to the implementation of P2P protocol software in the network after the first-level NAT networking is upgraded to a two-level NAT networking. application.

[0064] At present, P2P software is widely used. Common downloading tools such as "BT" and "EDonkey" all belong to P2P software. An important feature of this type of software is its fast download speed. All user devices can provide "re-download" as a "server", that is to say, when a user downloads a file, it also provides other users to download from their own device. From the perspective of the user who is downloading, on the one hand, he is a "user" who downloads from many "servers" (each user device participating in the download can be regarded as a server); on the other hand, he is also another user. A "server" while downloadin...

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