Method for realizing packet traversal of network address translation equipment

Abstract

The present invention provides a method for realizing message passing through a network address translation device, including: S1, the intranet sends a message to the network address translation device, and the message carries the internal network IP address, the internal network security parameter index and the external network security Parameter index; S2. The network address translation device receives the message, and according to the internal network IP address carried in the message, the internal network security parameter index and the external network security parameter index and the public network Establish a mapping table for the IP address; S3. Convert the internal network IP address of the message to the public network IP address according to the mapping table, and send the message to the public network IP address through the public network IP address An external network device; the external network security parameter index is the security parameter index of the external network device. The present invention establishes NAT device address mapping, so that when the message in the IPSec tunnel performs NAT traversal, the port address translation can be performed without adding UDP.

Description

technical field [0001] The invention relates to the technical field of network communication, in particular to a method for realizing message traversal through network address conversion equipment. Background technique [0002] Network Address Translation (Network Address Translation, NAT) is a technology for accessing a wide area network (WAN). It is a conversion technology that converts an internal network IP address into a public network IP address. type of network. Due to the limited number of public network IP addresses in the network, a large number of NAT devices are used in the network to undertake the task of converting internal network and external network IP addresses and ports to alleviate the limited problem of public network IP addresses. [0003] In the prior art, a virtual private network (Virtual Private Network, VPN) device uses a method of adding a UDP4500 header to the ESP message to solve the problem that the port address translation cannot be performed...

AI Technical Summary

Problems solved by technology

[0005] The technical problem solved by the present invention is the problem that the port address translation cannot be performed without adding UDP in the NAT traversal of the Internet protocol security (IPSec) tunnel

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