X Research source On a network diagram, the typical symbol for a VPN is a padlock. A VPN filters all internet traffic through an external proxy server, which makes it almost impossible to trace the IP address of any of the devices connected to the network. This is a must for any private network connected to the internet.
If it is a wireless router, add two antennas to the top of the circle. The arrow on top points up, and the arrow on bottom points down. The two arrows on the left and right should be pointing inward. The industry standard symbol for a router is a circle with four arrows arranged in a cross in the middle. X Research source If your router is connected to the internet, draw a line from the cloud symbol to the router symbol on your diagram. This may be between your private network and the internet, your private network and your server, or different networks that are connected to each other.
Some firewalls also have antivirus software and threat detection built in. They can be set to block or allow traffic based on state, port, or protocol. This can protect any network that is connected to the internet.
That is, if your private network has an internet connection. When creating a network diagram, start with a cloud symbol to represent your internet connection. The industry standard symbol for the internet connection is an icon that resembles a cloud.