Remote Desktop Control - Frequently Asked Question

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How to access from the Internet a remote PC behind the router?

It is possible a situation when remote computers are located in the local area network (LAN) behind a network address translation (NAT) based router and you want to control that PCs via Internet.

You will not have any problems and obstacles if you are using Online Gateway connection mode to access these PCs as router doesn't require any additional configuration in this case.

However there is a difficulty in Direct Connection mode if remote computers have no public IP addresses, i.e. addresses are private (192.168.x.x or 10.x.x.x for example); and only the router has a public IP address (something like 210.20.160.22) is accessible from the Internet.

In that case, you need to configure "Forwarding" on the router/firewall to control internal LAN computers from the Internet. You should configure your network hardware to forward connections from a port on the router to a specific IP address and port of the target computer inside your computer network. It is necessary to assign at least one unique port on the router for every internal computer you need to control.

Remote Desktop Control uses 2 TCP port 6279 and 7279 by default.

How "port forwarding" works?

Terminology:

  • Port on the network PC is a private port. Network PC is private.
  • Port on the router is a public port. Router is public.

Router should forward traffic from its different public ports to different private computers.

Let's consider an example

You have local network with 3 PCs and 1 router. Admin Module is located anywhere in the Internet, but outside this network.

You want to control network PCs via Internet when you use the admin's PC.

  • Public IP address of router is 210.20.160.22.
  • Private IP addresses of network PCs are: 192.168.0.2, 192.168.0.3, 192.168.0.4

In this case the configuration of the "port forwarding" can be the following:

  • 210.20.160.22 : 6279 -> 192.168.0.2 : 6279
  • 210.20.160.22 : 7279 -> 192.168.0.2 : 7279
  • 210.20.160.22 : 6278 -> 192.168.0.3 : 6278
  • 210.20.160.22 : 7278 -> 192.168.0.3 : 7278
  • 210.20.160.22 : 6277 -> 192.168.0.4 : 6277
  • 210.20.160.22 : 7277 -> 192.168.0.4 : 7277

For connecting to some network PC via Admin Module you always use external IP address of router (210.20.160.22), but unique pair of port numbers (6279 and 7279; 6278 and 7278; 6277 and 7277) to connect each network workstation.

You should enter these values into the Admin Module address book ("Add new PC" button) and change default ports in the Host Module settings on each workstation.

In this example for connecting with computer 192.168.0.3 you should enter in the admin address book:

  • IP address: 210.20.160.22
  • ports: 6278 and 7278

On the Host PC 192.168.0.3 you should change default ports to 6278 and 7278.

You can read how to configure your router's model here: Routers Index

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