Making your Computer Accessible from the Public Internet

This item is for people who want to make their server-based software programs accessible via the public Internet. Examples of this would be if you were setting up Axon and IVM as a VoIP system and needed to allow customer computers to call you from the Internet. Another would be if you were setting up BroadCam, and you needed to allow computers to be able to access a video stream that resided on your computer.

Examples of server programs include:

Axon VoIP Based PBX (uses TCP and UDP)
ScreenStream Desktop Sharing Program (uses TCP)
BroadWave Audio Streaming Server (uses TCP)
BroadCam Video Streaming Server (uses TCP)
WebDictate Online Dictation Recorder (uses TCP)
IVM Answering Attendant (uses TCP)

Allowing computers on the Internet or “WAN” to connect to your home computer on the local network or “LAN” requires a few things (in this order),

Having a “rule / exception” for the stock OS firewall, that allows a connection to be made from WAN to LAN.
When you install an NCH application that requires computers to access it from the internet, it will generally create a rule automatically in the stock firewall that comes with Windows.
You can check this in both XP and Vista by going Start > Control Panel > Networking Connections > *select appropriate adaptor* > Properties > “Advanced Tab” > Firewall Settings > Exceptions.
How to manually open ports in Internet Connection Firewall in Windows XP
Having an “rule / exception” for any aftermarket, or third party firewall that is present (Norton’s, Zone Alarm, etc)
If you have a third party firewall installed on your machine, one exists on your modem or one is included with you’re antivirus application, you need to create a "rule / exception". To learn how to modify these third party firewalls, please click here for more information.
If you cannot find a reference to the firewall that you are using, you may have to check if your firewall comes with help documentation, or you can alternatively search the Internet for a help guide.
Having a “rule” to pass any attempted connection from the WAN to a computer on the LAN. This is called “forwarding a port”
The basic premise or forwarding a port is much the same as making a "rule / exception" for a firewall, and generally the same across all router / modems. The easiest way to learn how to do this with your particular router is to use the very thorough resource, www.portforward.com.
- First make a note of your IP presented at the top of the list.
- The main page has a list of the most popular routers available, locate and click on yours (Be sure not to click on the advertising for PFConfig (NCH are not affiliated with the site or product. Click on “skip ad” on the top right hand corner)
- Click on the link in the sentence “If you do not see the program you are forwarding ports for, be sure to visit our Default Guide for this router”
- Here you are given instructions on how to forward the port from the Internet or WAN to your LAN. You need to set the same port, in which you designated in the NCH application.

Hairpinning Issues

Note that sometimes when testing your IP from within your network you may not not be able to connect to it. This just means your router does not 'hairpin' packets. To connect to the server from within your own network you need to use the private IP address (and private port) of that server. From outside the network though (i.e. across the Internet) you can use your public IP address (and public port) to access it.

If you require any more understanding on the topics and terms listed here, it is highly recommended that you read the guides listed on www.portforward.com under such subjects as;