What Does a Router Do? An Intro to Port Forwarding
To understand port forwarding, you first have to the understand the basics of routers. Every Internet Service Provider assigns an IP address to an internet connection but every computer/device on a network needs a unique IP address to function properly online. But you may have noticed that all the devices on your network have the same IP address. This is because they are connected to a router who is sharing that one IP address by assigning locations.
If connected to a router, your local IP address will usually look like 192.168.xx.xx. This is the address of the private local network created by the router. On the other hand, to the outside world, the router displays the IP address which your ISP has provided you.
This is easy when you are using a private network to send some information. But when it comes to receiving information, the router does not know whom to deliver it to. Port forwarding is a simple and popular networking solution that tells the router which computer on the network the information should go to.
Think of Port Forwarding as an office mailbox with a bunch of slots. They are all at the same address but each slot is assigned to a specific person so the mail can be directed to each individual in the office.
How do you use port forwarding routers?
There are four easy steps to setup and use port forwarding on a DD-WRT router. Before you start setting up your port forwarding, make sure that your router is in working condition and the internet connection is active.
You may also want to find the recommended ports for different applications, so you are prepared when you start setting it up. Visit this extensive list on PortForward.com to find the right ports for your applications.
If you are looking for a DD-WRT router to use for port forwarding and many other upgraded services, you can purchase one in our FlashRouters DD-WRT Routers Store.
#1: Find your IP Address & Open the Router’s Admin Console
To determine the IP address of your router, use this simple step:
- For Windows 7/Vista: In the Start—>Search Programs and Files area, type ipconfig/all & press enter press enter. Then look for the area that says Default Gateway.
- For Windows XP: Click Start button then Run. type ipconfig/all & press enter press enter. Then look for the area that says Default Gateway.
- For Mac: Enter netstat -nr in the command prompt.
- For Linux: Enter ifconfig wlan0 in the command prompt.
Type the IP address of your computer into the URL box of your web browser to open the router’s admin console. Oftentimes, the default router gateway address is 192.168.1.1.
#2: Type in Your Username and Password
Enter the username and password you chose while you configured the router’s security configuration. If you have not yet configured the security settings, enter the default username and password for dd-wrt which is root and admin. We recommend you never leave the default username and password. Always change it to increase the security for access to your network.
#3: Go to the Port Forwarding Section
Different DD-WRT builds may have a different interfaces. On the most recent builds, navigate to the NAT/QOS and you will find an array or port related options including Port Forwarding, Port Range Forwarding, Port Triggering, & UPnP.
#4: Configuring Your Ports
It is recommended to set static IP addresses for any computers you would like to forward ports to. Do this using Static DHCP or by manually configuring IP assignment on your devices. Be sure to set your static IPs outside of your automatic DHCP address pool/range. By default DHCP assigns address from 192.168.1.100 to 192.168.1.149 .
If you want to configure for a specific port, click the NAT/Qos Tab—> Port Forwarding subtab.
- Click Add and a new empty row will appear.
- Enter the name of your Application such as BitTorrent.
- For Protocol, unless you know otherwise, choose Both.
- Sourcenet is the IP address or range of WAN IPs that are allowed to be forwarded. If you do not wish to restrict, leave it blank. Unless you have a specific reason for this, leave the Sourcenet field blank.
- Under Port From, enter the port you’d like to forward.
- Under IP Address, enter the IP you’d like to forward the port to.
- Under Port To, enter the port you’d like to forward to. Often this is the same port, this action is redirecting the information to go directly to that port but specifically on your machine assigned to expedite the process.
- Click Save.
- If you want to add more forwards, click Add. If you are done, click Apply Settings.
- To complete the Port Forwarding setup, reboot your router. Go the the Administration Tab, scroll to the bottom and click Reboot Router.
How to Troubleshoot Port Forwarding
- If you turn on Universal Plug n Play (UPnP) option in DD-WRT, it will overwrite static port forwards that you set here. If your static port forwarding is important, turn off UPnP.
- This may sound simple but is often the cause of the confusion. Check your information! Ensure that all the numbers (IP addresses, ports) are correct. Even a single missing or extra digit will cause the application to not work accordingly. Everything should be double checked to make sure that no error comes up while running the application.
- Each time your computer is turned off, your IP address may change. If this happens, change the information in the admin console and port forwarding. Static IP address assignments are advised in order to prevent such issues as mentioned above.
- Check the DD-WRT Wiki for Port Forwarding Troubleshooting for more helpful tips.