Technology

Configuring an Internal PC for External Access

With the adoption of firewalls and routers, connecting to another computer via the Internet has become a real challenge. If you’d like to configure your computer so external access is possible, there are some in-depth configuration changes that you need to make to your network.

Obtain your IP Address or DynDns Address

The first step to locating you is to get your address. In the Internet world, this is known as an IP Address and can be easily tracked down.

  1. Find out whether have a Static (unchanging) IP address or a Dynamic (changing) IP address. Chances are that if you’re DSL or even DSL Pro that you have a dynamic IP address. If you’re on Business DSL or a Cable Modem, you’re most likely static.

    This is the IP address that is assigned to your entrance point to your network. If you are static, there’s no worries. If you are Dynamic, sign up for a service such as Dynamic DNS. Most modern routers have the ability to communicate with DynDNS to keep your IP address updated. Then, rather than providing someone with your IP address, you would provide them with a domain such as findme.homeip.net.

  2. If you don’t know your external IP Address, you can use a site such as What’s My IP Address to find out.
  3. Ping your DynDns or IP address and see if you get a response (Open up “Command Prompt” or “Terminal” and Run: ping findme.homeip.net
  4. If you receive no response, you may need to enable Pinging in your router’s configuration. Refer to your router’s documentation.

Enable PORT Forwarding in your Router

Now that we have your address, it’s important to know what door to enter your home through. This is known as a PORT on a computer. Different applications utilize different PORTs, so it’s important that we have the right PORT opened and routed to your computer. By default, the majority of routers have all ports shut down so no one can get into your network.

  1. In order for the source PC to communicate with the destination PC, your Router needs to direct the traffic to your PC.
  2. We spoke about the importance of a Static IP Address for your network, now it’s important that you have a Static IP Address for your PC on your Internal Network. Refer to your Router documentation on how to configure a static IP Address for your Internal PC.
  3. Depending on what kind of application you wish to connect to, you will have to enable PORT forwarding from your Router to your PC’s internal static IP Address.
    • HTTP – if you wish to run a web server off of your internal PC and make it accessible externally, PORT 80 will need to be forwarded.
    • PCAnywhere – 5631 and 5632 will need to be forwarded.
    • VNC – 5900 will need to be forwarded (or if you’ve configured a different port, utilize that one).

Enable Firewall Settings on your PC

  1. The same PORTS that you’ve forwarded to your PC will require enabling in your PC’s Firewall software. Refer to your firewall documentation and how to enable the application and/or ports you wish to have accessible externally.

Making these configuration changes aren’t easy, but once it’s all working well you should be able to access your PC via the application of your choosing from wherever you’d like.

NOTE: Regardless of whatever program you are utilizing, be sure to apply a very difficult username and password! Hackers like to scour networks in search of open ports to see if they can access and/or commandeer those PCs. Additionally, you can also restrict the IP addresses that you will provide access to.

Leave a Reply