How to open the doors of the router

Even if modern routers automatically manage most of the network functions, it may be required to open the door for some applications to work on the internet
for a particular program or network device . Although the concept may not be easy to fully understand, opening ports on the router (which is called port forwarding in English) is a very simple operation to do if you know where to look.
In this guide we will show you in detail what it means to open the doors in a modern modem / router and we will also show you how to do this on most of today's modems, including those supplied on loan for use by the operator (usually the simplest to be configured).

Guide to open the ports of a modem or router

Before showing you how to open the ports of a router, we will show you what it means in computer terms to "open the ports" on these network devices and why we have to do it for some programs or for some devices.

What does it mean to open doors (Port Forwarding)

As for the meaning of port, it is a number comparable to an address. A bit like the street numbers of the buildings of a street (the street in our case is the router or modem we are using), the door number clearly indicates which building or house the "virtual postman" must knock on (in this case the packets arriving or leaving our router). These ports are normally closed by routers to prevent viruses or people capable of using them to penetrate the internet into our devices.
Some programs (like BitTorrent but also a webserver or online game) need to open a certain port and "leave it open", so that the packets that reach the router are forwarded correctly.

Some ports have been reserved for specific applications common across the IT industry.
For example, when loading a web page the browser uses port 80 to serve HTTP requests.
If an HTTP request was sent by the web browser on a different port, the server would not recognize it and would not be able to respond by loading the site.
Most of the ports, however, are not assigned and can be set, by writing any number such as 1200 or 32400, in the connection options of each program.
To learn more, I refer to the guide on how a router works, in order to be more familiar with the terminology and how the home internet network works.

Why you need to open router doors "> A technical example is to be able to access the security IP camera that is connected to the home router, through our laptop used from outside the home. To do this, simply connecting to the IP address is not enough of our connection (provided that this is static and reachable from the outside), it is also necessary to indicate the door.

Port forwarding is also important for those programs like BitTorrent or Emule, where they exchange files with other people in P2P, for online games like Minecraft when you want to host a multiplayer game on your PC, for remote desktop programs like VNC and all applications where you need to open an input on your computer .

Requirements to open doors correctly

Before configuring the router to open the doors it is necessary to retrieve some important information, without which we will not be able to perform the task.
As a first step it is necessary to set a static IP address on each device used and not to let the router assign IP dynamically according to the device turned on; in this regard we can read our guides on how to set a fixed and static IP on a Windows PC and Guide to DHCP: Assign IP manually or leave the automatic IP "> the Web page Whats-My-IP-Address.

The IP address provided is often dynamic (it changes every time the router is restarted), but some operators provide a static and unreachable IP from the outside (such as Fastweb): in this case, just contact customer service and ask for help. 'assignment of a static and public IP address.
If we have a dynamic and public IP we advise you to configure a dynamic DNS, very useful to always be reachable whatever the IP assigned by our operator: we will thus obtain a personal Web address that always "points" to our network, any IP we use at moment.
To conclude, we perform a check on the local firewall (if it is installed) and we grant authorization for the program on which we intend to open the doors, so as not to have problems later (even in the case of a good configuration, the software firewall may block requests arriving). In this regard, we invite you to read our guide on how to activate the Windows 10 and 7 Firewall: configuration guide and restore it .

How to open the router ports

Now we can finally open the doors on the router, taking into account that these instructions, which may not be precise for each model of router, are universal in general.

• We enter the router configuration panel, typing the router address in the address bar of any PC connected to the home network (via Ethernet cable or via Wi-Fi). Typically this address is 192.169.0.1 or 192.168.1.1 but this address can be obtained quickly by opening a command prompt from the Windows Start menu, running the ipconfig command and reading the address in the Default Gateway field.
• We access the router with name and password : the most common credentials are admin / admin or admin and no password or Administrator without password; if we do not remember the password of our router, we advise you to read the instruction manual, to check the label on the back of the box or the appliance or to read our guide on passwords and default logins for all the Routers .
• Let's configure the door : the option to be identified may be called differently based on the router model in our possession; we can find Port Forwarding, Port Forwarding / Activation, Forwarding / Virtual Server, Port Mapping or Port Enable . This option is often found in the Advanced or Advanced settings of the WAN or Internet configuration.

Once clicked on the option to configure new ports, we will get a panel where you can give a name to the new rule, indicate which port or range of ports to open and to which IP address to assign forwarding between the devices of our home network.

You must specify the TCP port, the UDP port or both, depending on the program and correctly enter the IP assigned to the device where the program on which to open the ports is present : if for example the port to be opened is 1456 of type TCP and the IP address of the device is 192.168.1.4, make sure that the 1456 TCP port is opened towards 192.168.1.4 (the most modern routers will allow you to forward directly to the names of the devices).
The number of ports can be any one between 1 and 65353 . Low numbers are most used by standard services such as the browser or e-mail program and many of the higher numbers are used by fairly common applications. At the end of the modification do not forget to save the settings, so as to make them effective.
To check if the door is open, open a web browser on the PC, go to the Yougetsignal.com website, insert the previously configured door and press the Check button to check that it is actually open.

If we get a green flag and the writing Port XXXXX is open on, the door is open and can be used without problems by the program or by the device that requires it. If instead we get Port XXXXX is closed on, we carefully check all the steps and make sure that there is no additional firewall to configure.

Conclusions

Opening the ports on the router may seem a little laborious, but once you have learned all the steps, it becomes one of the easiest operations to do on our modem. For some types of internet connection, opening doors is not necessary, for other types such as the Fastweb connection it is vital.
In another guide we have shown you the steps to take to configure the ports on Fastweb routers, so as to be more precise.
If desired, we can also use some programs to configure port forwarding on the router .
If, on the other hand, we wish to close the doors from a Windows PC, we refer you to our guide on How to block doors on a Windows PC .