The Application Layer Gateway service in Microsoft Windows provides support for third-party plugins that allow network protocols to pass through the Windows Firewall and work behind it and Internet Connection Sharing. ALG plugins can open ports and change data that is embedded in packets, such as ports and IP addresses.
Microsoft Windows' Application Layer Gateway service supports plugins that allow network protocols to pass through the Windows Firewall and work behind it, including Internet Connection Sharing. These plugins can alter data in packets, like opening ports and changing IP addresses.