Most organizations today employ a range of security measures to protect their computer networks from hostile intrusion. One of the common measures includes creating a firewall. A firewall is a system designed to prevent unauthorized access to a private (internal) network. Firewalls can be implemented either as hardware or software, or a combination of the two.

The most common use of a firewall is to prevent unauthorized intrusion from Internet users attempting to access a private network or Intranet. A firewall examines all traffic entering or leaving the internal network/Intranet, ensuring that traffic meets security criteria established by the Network Administrator.

RemotelyAnywhere can be configured to work with a firewall-protected computer. This requires mapping an external, incoming port on the firewall to the internal IP and port on the computer running RemotelyAnywhere. Routers, on the other hand, operate in much the same way as firewalls. They both offer the opportunity to open and map ports to specific computers. For the rest of this document, the term "router" can be interchangeable with "firewall."

From outside your LAN, you would gain access to the computer running RemotelyAnywhere by entering the firewall's IP address and the port to which the desired machine is mapped. For example:

Router: External IP address: 111.111.111.111

RemotelyAnywhere computer: IP address: 192.168.0.10, Port: 2000 (port 2000 is the default but this can also be changed).