How can you determine whether your Internet network has a public or private IP address and what the differences are?
This is a topic of general interest, as we all have internet service at home. If you use it to watch Netflix, YouTube, social media, and download music and movies, you are probably happy with your current ISP. By ISP, I mean “Internet Service Provider,” or simply the company that provides you with internet service.
However, if you have a Play Station at home, play online on your computer, or have or plan to install security cameras in the near future, you are probably not entirely happy with your current ISP. Typically, residential internet plans are not equipped to optimally handle some of these situations, and this is usually due to the fact that these plans have a private IP address and have restrictions at the Internet level, which is not the case with the public IP that is usually delivered in corporate internet plans.
An IP address is a set of numbers that identify a computer or device on a network. More precisely, it is the logical or "virtual" identifier of the network card of that computer. A public IP address is the computer's Internet-wide identifier. This means that it can be seen and located on the Internet. In contrast, a private IP address is not visible on the Internet but only within a specific private network, and therefore has restrictions on Internet access.
In the case of ISPs, they can provide internet service to their subscribers by assigning them a public IP address or a private IP. The most normal case currently is the second one in order to reduce costs and due to the limitations of public IP addresses. In any case, whatever the type of IP, it will be linked to the subscriber's router.
Since a public IP address can be seen or located on the Internet, it has a direct or free connection to any device or service over the Internet. Since there are no intermediaries involved, there are no problems connecting to the Internet. This is not the case with a private IP, which, although it gives subscribers access to the Internet and will generally not have problems in normal use, there are instances when it will be a problem.
Ports
This is where the issue of ports comes in. When two computers establish a connection, for example, a subscriber’s router (or a device on your network that will connect to or from the outside through that router) and a server on the Internet, they do so through communication channels called ports. These ports must be open or free for there to be no problems with the connection. When an ISP assigns a private IP address to a subscriber, that IP address is assigned by a server that controls that connection and becomes a wall or barrier between the subscriber and the Internet. This is known as strict NAT or CG NAT.
If the ports on the ISP server are blocked, there is a firewall or restriction of free connection, which always happens. Even if you open the ports on your router, you will have problems with the services, especially with regard to remote access. ISPs do this in order to protect against external attacks on their networks and computers, as well as on their customers.
How do I know if I have a public IP address?
To find out if you have a public IP, you should check the IP address that appears in the WAN information on your ISP's router or modem. Public IP addresses can have 1 through 191 in the first octet (except for IP addresses whose first digits start with 10.0.0 and 172.16.0). Here are some examples of public IP addresses:
98.137.11.163
157.240.6.35
172.67.138.108
The first eight of these IP addresses, 98 , 157 and 172 , fall within the indicated range and are therefore public IP addresses.
How to get a public IP
The traditional thing to do is to ask your ISP for it. Some can customize it to their residential or home internet plan for an additional monthly fee.