I need to open a port on my router or firewall. How do i do that? What is that? Should I Be Scared?? ~ Ask The Admin

Monday, December 31, 2007

I need to open a port on my router or firewall. How do i do that? What is that? Should I Be Scared??

New Years is almost upon us and the Admin needs some rest - maybe a day off? Yeah right we have even more emails today! This has been a big year for the AtA gang - stay tuned for more of our geeky flavored content in 2008.

Our reader Diego has an application on his computer that he needs to get access to while he is away. Diego is trying to get VNC going on his iPhone. This tutorial is for you no matter what router you are on but, it uses the WRT54G as an example. You should be able to use the knowledge to work with most modern routers. To begin there are a few things you need to do. First as a prerequisite you need to know the difference between external and internal ip addresses.

Now you see that you can't get to your internal addresses also referred to as your NAT IP from outside without some work. You are in a protected kingdom. (Pardon the corny references but they work well!) The inside of your network is like the inside of your virtual castle. The only way in is by opening a port sort of like building a virtual draw bridge. To open this draw bridge to your computer over the internet you need your computer to have a static IP address.

Now we need to see if you are using a static IP or a dynamic IP. Do you know how to tell? In Windows this is done by:

  1. Right click on the my network icon
  2. Choose properties
  3. Right click on the icon that represents your Connection
  4. Choose properties.
  5. Scroll down to Internet Protocol and click Properties.
  6. If the check box is checked to obtain an IP address automatically then We want to check the Use The IP address. BUT don't fill in anything or click OK yet We will get right back to this as soon as we get the address to fill in!
  7. Now we want to goto DOS and find your current IP address. Goto Start
  8. Run
  9. Type in CMD and hit enter
  10. Now type ipconfig /all
  11. and write down your IP address, subnet mask, default gateway and DNS servers. We Will now fill this address information into the address box we left blank a moment ago.
  12. Now you have a static IP address and are half way there! Now goto this link here:

Plug in your static IP we set above and follow the rest of the instructions and you will be remote controlling your PC from your Shiny iPhone in no time! Let us know how it works out for you!