This guide is intended to help anyone who is not been able to port forward TCP/UDP traffic from the internet, through their home router to its intended destination. If you are using a DSL modem and have already checked and re-checked your port forwarding settings and www.portchecktool.com still reports an error you may have to bridge your DSL modem.
Some DSL modems come pre-configured and are initially setup to act like a stand alone router or firewall. This prevents inbound traffic to pass through the modem and get routed to your home router. The upside to this problem is there is an easy fix. We will disable the PPP login on the DSL modem and instead move these settings to your router. This is done by placing the modem into a Bridged mode and then using your ISP/DSL connection settings on the router.
If you are un-sure about your username/password or your specific DSL settings, PLEASE contact your ISP and speak with a tech. They will be able to walk you through this process.
Step 1. Log into the administrative area on the DSL modem. You may need to contact your ISP to find the address for your modem but most vendors will set the modem up on http://192.168.1.254
(below is what a Motorola DSL modem will look like)
If you do not have the login for the modem you will need to contact your ISP/DSL provider for this information. You may also attempt to look this information up online.
Warning: Changing settings to your DSL modem may cause connectivity issues.
Step 2. Find the PPP-OE settings, this is generally in the "Advanced" area on the DSL modem. There should be an option to set up the modem in bridged mode. This will now allow your router to be the main routing device on the network. You will now need to login to your router to setup the PPP-OE username and password.
Configuring your Router
Step 3. This is where is gets a little tricky as now you have to configure your router for PPPoE so that you can place your ISP username and password into the correct fields so that your internet connection works! For the best reference I would suggest consulting your Router's manufacturer as there are many different brands and model of routers that it would be too much to contain here.
However, there is a general setting that you would be looking for such as connection type, this would need to be set to PPPoE for most configurations. For example: AT&T DSL uses PPPoE connection configured with your Username@isp.net and a password that you created during a registration process. Setting your router to the PPPoE with your username and password would allow your router to function as the required PPP client that your ISP requires.
Congratulations you've just configured Bridge Mode! Once the modem resets, you can go check your service again at www.portchecktool.com. If you experience any issues connecting to the internet, you will want to undo this change and contact your Internet Service Provider (ISP).