Method for allocating NAT (network address translation) port resources in distributed system

Abstract

The invention provides a method for allocating NAT (network address translation) port resources in a distributed system, belonging to the technical field of network communication. The method for allocating NAT port resources in a distributed system specifically comprises the following steps: a first message in a first session state triggers the NAT module of a present service board to apply for N port resources to the NAT module of a control board while passing through some service board; a port is taken, and the conversion information of the taken port is obtained by the first message; the first session state is stored on the present service board, and the follow-up messages in the first session state are forwarded on the present service board according to the session state stored on the present service board; when a first message in a follow-up session state passes through the present service board, the NAT module of the service board takes a port from the remainder N-1 ports; the first message in a follow-up session state obtains the conversion information of the taken port, and the follow-up session state is stored on the present service board; and the follow-up messages in the follow-up session state are forwarded on the present service board according to the session state stored on the present service board.

Description

technical field [0001] The invention relates to the technical field of network communication, in particular to a method for allocating NAT port resources in a distributed system. Background technique [0002] NAT (Network Address Translation, Network Address Translation) is currently a commonly used solution to the shortage of IPv4 addresses. In the network egress of a secondary operator or the business egress of a large enterprise (more than 10,000 people), the gateway device must have the NAT function. In this scenario, due to relatively high processing performance requirements, the performance of centralized devices cannot meet the requirements, and the deployed gateway devices are usually distributed devices. [0003] In practical applications, NAT can convert only IP addresses, or simultaneously convert IP addresses and ports of the TCP / UDP protocol. The latter is most widely used in gateway devices, and the NAT mentioned in the documents of the present invention all ...

AI Technical Summary

Problems solved by technology

[0010] The disadvantages of this implementation method are: the scalability is not good, all the process of establishing a session state must go through the control board, and the requirements for the control board are very high. When many service boards are configured, the processing performance of the control board will be reduced It will become a bottleneck; the process of creating a new session state has a large delay, and the first message of a new session state must go around the control panel, resulting in a large delay in the message. The intuitive reaction to the user is that the speed is slowed down. Web pages slow down

[0014] The disadvantage of this implementation is that port resources may be greatly wasted. In the case of uneven services, there may be port resources on service board 1, but the port resources on service board 2 and service board 3 The situation that has been exhausted; does not support the hot swap of the service board, when inserting or pulling out the service board, there is no way to automatically allocate or recycle port resources for the service board, and the system needs to be restarted, causing the network to be disconnected

After restarting the system, the port resources reserved on each service board are 16K. In the second step, the service board 4 is unplugged. There is no way to automatically recover the port resources on the service board 4. Service board 1, service board 2, and service board 3 There are still 16K port resources on each board. After restarting the system, the port resources reserved on each service board (service board 1, service board 2, and service board 3) are restored to 21K

Images