WAN port: IP address list, which needs to list all accessed IP addresses/subnet masks, configure gateway and DNS address (important);

Static routing: you need to indicate the gateway address of the network segment of the intranet, and then go out;

Strategic routing: a pool of network addresses representing telecommunications, China Unicom, mobile and educational networks.

Port mapping: Add intranet addresses and ports corresponding to all extranet ports, specify the destination address segment as extranet address and the destination port as extranet port, map IP addresses and ports into intranet addresses and ports, check the firewall to automatically release data and publish the server (allow intranet users to access intranet servers from extranet IP), otherwise, intranet users will have problems accessing intranet servers using public domain names.