The dangers of public IPs

[harlan4096]

Almost every ISP offers an option to use a public IP address. Other names are “static IP,” “Internet-routable IP,” and sometimes “real IP.” Some people buy this option having a specific purpose in mind, some opt in just for the sake of it. However, public IP addresses can pose numerous risks. To find out what they’re all about, who might need them, and what the dangers are, read on.

What’s an IP address, and how does it work?

If you want to send a friend a postcard, you need to know their address. Without it, the postcard won’t be delivered. The Internet is roughly the same. All online actions, from checking mail to watching cat videos, require data to be exchanged between your device and the host servers, and each participant in the process must have its own address.

For example, to open a page in a browser, your computer must contact the server at its address, and the server sends the page back using the computer’s address. The request and response are both transmitted by means of packets containing the addresses of the sender and recipient, just like with snail mail. Such addresses are called IP addresses, and they are written in the form of four numbers from 0 to 255, separated by decimal points: for example, 92.162.36.203. This yields a total of just over 4 billion possible combinations, far fewer than the number of devices connected to the Internet.

To remap and preserve IP addresses, NAT (network address translation) was conceived. Simply put, it works as follows: ISPs use one external public IP address for all of their subscribers, assigning internal private ones to each of them.

Full reading: https://www.kaspersky.com/blog/public-ip-dangers/24745/