Method and system for binding router interface supported by static state PAT

The invention relates to a method and a system for binding a router interface by the support of a static PAT. The method comprises the following steps that: firstly, a static PAT rule for binding the NAT outgoing interface of the router is configured; secondly, the network address interface mapping relationship in accordance with the static PAT rule is established according to the network addressacquired from the outgoing interface; when the outgoing interface receives a TCP/UDP message of which the destination address is the respective interface network address, the network address interface mapping relationship is searched by the destination address and the destination port of the message, if yes, the network address port conversion is performed on the message according to the network address port mapping relationship; and otherwise, the message is taken as the local message of the router. The invention also provides a system for realizing the method. The method and the system can save the application for t