Operation Manual

Firewall – ALG
An application gateway is an application program that runs on the router. When a client
program establishes a connection to a destination service, it connects to an application
gateway, or proxy. The client then negotiates with the proxy server in order to communicate
with the destination service. In effect, the proxy establishes the connection with the destination
behind the firewall and acts on behalf of the client, hiding and protecting individual computers
on the network behind the firewall.
This creates two connections: one between the client and the proxy server and one between
the proxy server and the destination. Once connected, the proxy makes all packet-forwarding
decisions. Since all communication is conducted through the proxy server, computers behind
the firewall are protected.
You can select the pre-programmed ALG’s on this page.