This topic shouldn’t be as confusing as it is. However with all the information available online, IT IS. My goal is to explain how I configured my raspberry pi so It can be accessed from outside my home network. This is meant to be a tutorial for the novice, so feel free and let me know if i am successful in this mission.
- Ill assume you know how to SSH into your pi.
- Ill assume you are already connected to your home (WIFI) network.
- Ill assume you know how to access your pi’s IP address (if config).
- Ill assume you know how to view a video stream on a program such as VLC.
Quick course on Internal vs External IP address
External (Public) IP Address
Your Internet Service Provider (ISP) assigns you an external IP address when you connect to the Internet. When your web browser requests a webpage, it sends this IP address along with it. Your ISP uses this to know which of its customers are requesting which webpage. Also, any website that you visit will have access to this IP address.
Every website also has an IP address of its own, though you never need to know them. When you type in the domain name, such as “www.google.com”, a Domain Name Server (DNS) looks up the IP address for you, which is the real location of the website. In this way, domain names are like human-friendly names pointing to machine-friendly IP addresses.
Local (Internal) IP Address
If your computer is connected to a router with default settings, that router will automatically assign a local IP address to your computer. Your local IP address is hidden from the outside world and used only inside your private network. You generally don’t need to know much about it unless you’re trying to set up a game or web server.
The local IP address can change depending on what other devices are connected to the same network and in what order they were connected. Most network routers assign IP addresses starting at 192.168.1.2, and increment the last digit with each new device that connects.
For example: If you turn on your computer first and it is the only device connected to your network, it will probably be assigned the local IP address 192.168.1.2. Then if you turn on your laptop and connect to the network it will probably be assigned the local IP address 192.168.1.3. And so on and so forth (the IP address 192.168.1.1 is generally reserved for the router itself).
You can assign devices specific IP addresses in the router control panel, so that a device will always receive the same local IP address when it connects. This is called a static local IP address. Consult your router manual for more information.
Quick course on ports
Ports are virtual pathways on which Internet data flows. You probably know that data on the Internet is sent to and from IP addresses. What you might not have known is that all data sent to an IP address is sent on specific ports.
If we think of an IP address as a telephone number, then we can think of ports as telephone number extensions. Suppose you wanted to make a telephone call to a major corporation; Ford for example. If Ford only had one simple telephone line it would take a very long time for your call to finally get through. However, by using telephone number extensions, Ford can channel incoming calls to the proper locations and as a result handle many calls on one line as opposed to just one call.
Ports are like telephone number extensions as they allow multiple pieces of data to flow back and forth on a single IP address. In fact, port numbers are appended to the end of IP addresses just as extensions are appended to telephone numbers.
In other words, ports are numerical identifiers that make it possible for you to check your email and browse the web at the same time. Technically speaking, this is possible because browsing the web traffic generally uses port 80, and getting your email generally uses port 110.
Common port numbers
During my time fooling around with the pi, I have come across the following common ports.
- Port 22- SSH -Secure Shell (SSH) service
- Port 80 – http – HyperText Transfer Protocol (HTTP) for World Wide Web (WWW)
- Port 8080 – webcache – World Wide Web (WWW) caching service
- Port 21 – ftp – File Transfer Protocol (FTP) port;
- Port 8554 – RTSP
- Port 8090 – ?
There are hundreds of ports, reserved for different functions. All i am concerned with are the ones that I will be using for my pi.
Example 1 – I searched the internet for a way to stream video from my raspberry pi camera , to be viewed on my desktop . From this site the author provided me with code which i copied into my pi.
- raspivid -o – -w 920 -h 540 -t 9999999 |cvlc -vvv stream:///dev/stdin –sout ‘#rtp{sdp=rtsp://:8554/}’ :demux=h264
This program sends video out through port 8554 (see code). It is a rtsp transfer type. So in your streaming viewer (VLC) you would add :8554 to the end of your pi’s IP address.
- example – rtsp://192.168.1.105:8554/
Example 2 – Just like in example 1, I wanted to stream video from my pi camera to be viewed on my desk top. From this site, the author provided me with code which i copied into my pi.
- raspivid -o – -t 99999 -hf -w 640 -h 360 -fps 25|cvlc -vvv stream:///dev/stdin –sout ‘#standard{access=http,mux=ts,dst=:8090}’ :demux=h264
This program sends video out through port 8090 (see code). It is a http transfer type. So in your streaming viewer (VLC) you would add :8090 to the end of your pi’s IP address.
- example – http://192.168.1.105:8090/
Connecting Via WWW
So far all we have done is connect within our home network. What fun is that. I want to be able to view my security camera when i am at work or on the beach drinking a blue moon. So here is the fun stuff.
Login to the router. Go to http://192.168.1.1/ It would ask you for username and password. That info would be on a sticker on your wireless router.
Once logged in you want to go to the port forwarding menu. This depends on your provider and what software you have. If you google your provider and port forwarding, someone will provide a step by step walk through, anyhow I have FIOS, so I found these nice instructions.
Example 3 – with this example i want to configure my pi from example 2 to be port forwarded.
- Click the Firewall button on the top menu bar.
- Click Yes when asked about wanting to proceed.
- Click Port Forwarding from your left side bar.
- You’ll be brought to a page titled “Port Forwarding”. Follow these steps to add your port forward rule:
– Click the Select IP from menu dropdown. click “Specify IP” to manually type it in.
– In the Application to forward… dropdown, select Custom Ports.
– Click the Advanced button. This will give you more options.
– You’ll see a dropdown with Destination Ports as its title. Click “Specify” from the drop down menu. Type 8090 into this box.
– Last step! Look below to find the Forward to Port dropdown menu. Click the drop down menu and select Specify. Put 22 in this box. Now click Add and your new rule should be added.
So now, my port forwarding is setup as so:
100.65.36.40:8090 will forward to -> 192.168.1.170:22
- As we see above the external IP with port, forwards to local IP port.
I hope i helped you understand port forwarding a little bit more than before you read this. Enjoy and continue to Create!!
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