The advantages to use a static IP address

An IP address can be public (that’s it provided by your ISP) and private (the address associated to connected devices in a local network).
You can setup your own private IP adress by assigning a static or dynamic address. In the first case we decide the exact IP address we want associate respecting some criteria (IP range, correct subnet mask); in the second case the address is dynamically provided by the router within DHCP (Dynamic Host Control Protocol) and it will change each time the network connection is started/restarted.

It’s suggested to setup a static IP address in these cases:

- you need specific TCP/UDP ports opened (some programs to works correctly need to have specific ports opened in the router)

- home server (if you want to use your pc as a local server eg. web, ftp, etc… a static IP address best supports name resolution, so that a computer can be most reliably reached over the network by its host / domain name)

Moreover using static IP addresses on home networks gives somewhat better protection against network security problems than does DHCP address assignment.

To setup a static IP address you firstly have to identify your router IP address. In Windows commands prompt just type ipconfig

Like in the image example 192.168.1.101 is the dynamic IP address assigned, 198.168.1.1 is the router IP address.

You just need to go in the Properties of your network connection, then in the properties of Internet Protocol (TCP/IP) and change it.
Naturally you must choose one in the valid range (192.168.1.2 – 192.168.1.255) and use the correct subnet mask (see schema), in this case as the IP address is in the class C the subnet will be 255.255.255.0
Lastly setup primary and secondary DNS (you just need to write the IP address of your router in the first field and automatically it will be used the DNS server provided by your ISP, or you can use public DNS servers with the advantages that comes: no restrictions on web sites, best performances)

To apply these changes you must restart your network connection. Retype ipconfig command you will notice that now it will be used the static IP address you manually setup before.