IP stands for Internet Protocol. This protocol, like many others such as HTTP, TCP, UDP, etc., is responsible for establishing communications in most of our networks. Even a fridge can have an IP address! Also devices such as a router, a server, a telephone, a computer, a television, etc.
There is no device in the world that can communicate with another without having an IP. IP addresses are the numerical names that are assigned to a device as a “license plate” so that it can be called by other devices.
There are two types of IP: Public IP and private IP.
Both public and private IP’s are built in four number blocks . Each block is a number from 0 to 255 and is separated by a period (“.”). For example, a public IP address could be 184.108.40.206 and a private IP address, 192.168.0.11 .
The answer is no and yes. Wow, you will be stunned. I explain. A public IP can never be duplicated , since each Internet connection is unique. Within a private network, private IP’s cannot be duplicated either. But it is possible that, for example, a friend of yours does have a private IP for one of their devices and can match a private IP address you have for a device.
This is because, for example, any home has a network with private IP’s for their devices but it does not mean that your friend’s home network must have different private IP addresses. That is, in each home there is a router and this router assigns private IP addresses to each device that can match the private IP addresses assigned by the router from your friend’s house to their devices. Are you already understanding what an IP address is?
A public IP is the identification assigned by your internet provider to be recognized on the Internet . Just like you, you can’t go outside with the car without a license plate, you can’t go online without a reference or identification.
Normally these IP addresses are usually rotated by your ISP (internet provider) every time you restart the router or from time to time. These IP addresses are known as dynamic IP addresses . If for some reason we need to have a static or fixed IP address for a device, we must contact the ISP and request that they put it manually.
When the Internet was born there were very few servers and the only way to access them was to know your public IP address . If a person wanted to access a particular resource, it was not worth writing, for example, resources.com (mostly because there were no domain names yet), but had to know the IP address of the server where that resource was hosted. Imagine that the IP address of that server was: 220.127.116.11 .
Is it not useful, efficient or easy to remember all those numbers? Data centers continued to grow and were increasingly hosting more servers with more different information. It would be crazy to have to point or remember each IP address for each resource! That is why the domain names we know very well today were born .
Currently, we use the famous DNS ( Domain Name Servers ) to impersonate an IP address with a domain name . Now, to access a material of resources.com you no longer have to put the IP 18.104.22.168 but indicate resources.com . Using domain names has a huge list of advantages over using IP addresses:
A private IP address is exactly the same as public IP addresses, only these are characterized by being fixed for each device and are not accessible from the Internet . The typical example is that of a house where devices such as a computer, a mobile, a television and even a washing machine are connected to the same WiFi network or cable. This network assigns a fixed and unrepeatable IP address to each device so that they can recognize each other.
There are different ranges of private IP addresses that we will see below. For now, I want to give you an example of what it would be like to have private IP addresses in a small home environment:
Unlike public IP addresses, private ones are assigned a range based on the type of network that we will see next. Public IP addresses are free, anyone can touch you:
Then there are other types of ranges, but we will not see them. If it is already difficult to see those of class A and B, the D and Y even more. As I said before, class C are the ones we see daily and start at 192.168.XX
You have to be very clear that your private IP address is totally different from the public IP address. The latter will only be used when you go surfing the Internet.
The netmask allows the same IP address to be used for two devices. For example, you could have the address 22.214.171.124 under two different masks making them serve to identify both. The masks are also those that allow to separate the networks in the different categories that we have already explained. The netmask is the one that dictates how many networks can be created and how many hosts can exist according to the kind of private IP we have. Remember that we already know what the types of IP classes are, we saw them above. As a general rule and sure that you have seen it thousands of times, the main network mask that exists is 255.255.255.0 , which is the one assigned to type C networks .
Without entering into a lot of very technical data or the reason, blocks 255 represent the amount of networks that can be and the numbers 0 how many hosts there can be . It is not that there can be 255 networks and 0 hosts. That is the human translation so that we can understand that if we translate 255.255.255.0 to binary code, it will be such a code: 111111111111111111111100000000 . Would you remember that number of bits of the binary code? Those 1 and 0 are the ones that dictate the type of network, the limit of networks that may exist and the hosts that may exist .
For example, for not complicating the thing much: we know that the net mask 255.255.255.0, translated into binary, has eight (8) zeros (0). Ergo if we raise two (2) to eight (8) we get 256. That 256 is the number of devices that may have connected to the same network. Well, we should know that although theoretically there are 256 opportunities, in practice we have 254 since, for example, we use one for broadcast , which is usually 192.168.1.255 .
Keep in mind that we have simplified these masks. There may be masks with numbers other than 0 or 255, such as: 255.252.0.0, 255.255.255.128, etc.
If already explaining what IP addresses are a bit messy, imagine when I explain now what IPv6 addresses are . As it turns out, IPv4 addresses are what we have been seeing now and IPv6 addresses are a new type of protocol that comes to replace IPv4 because there are almost no IPv4 addresses left and you have to jump to IPv6 addresses. We are not going to go into much matter, I just want to leave as a curious fact:
While IPv4 supports 4,294,967,296 (2 32 ) addresses, which is just under 4.3 billion, IPv6 offers 3.4 x 10 38 (2 128 ) addresses, a number similar to 6.67126144781401e + 23 IP addresses for each square meter on the surface of the Land.
Curious, right? IPv6 addresses are the future. Well, rather the present already. Its composition is different from that of IPv4 addresses, since the former play with alphanumeric characters . Therefore, the combinations are endless.
If for some reason you need to know what your public IP address is, we, who always help customers and non-customers, explain it step by step. You can use one of our tools that tells you at all times what your IP is. To do this, access this page. Upon entering, a little below, you will see your public IP:
On the contrary, in this case you need to know what your private IP address is in Windows . Unlike to know the public, this process requires a somewhat more complex path. But it is not difficult, just follow the steps you will see below. We will use Windows 10 although in Windows the form is common in all its versions. On Linux or Mac, these are other steps, which we will see later.
Indicate in the search engine or in ‘ Cortana ‘: EXECUTE or press the Windows symbol and, keeping it pressed, press the «R» key (without the quotes). Click on the result and a box will open .
Write in that box: CMD
Press ENTER or click OK. A small black box will open with the cursor ready to write.
Type: ipconfig and press ENTER.
Look at the result and look for the line that says IPv4 address and IPv6 address .
What is marked in red are your private IPv4 and IPv6 addresses . You’ve got it!
In this case we will use the Ubuntu distribution as an operating system to teach you how to know the private IP address in Linux .
There are several ways to access the terminal. One of the fastest is to press the « Control + Alt + T» keys (without the quotes). You should open the terminal:
As we did in Windows, the next step is to put the command that returns the information we are requesting. If we put ” ipconfig ” it will give us an error, since this command is reserved for Windows. In this case, what we have to use is a “synonym” called ” ifconfig “. We indicate this command in the terminal and press ENTER.
What we see indicated are our private IP addresses in Linux . The first red box corresponds to the IPv4 address and the second corresponds to the IPv6 address .
Extra : If putting “ ifconfig ” gives you an error like the one you are going to see next, it is because “ ifconfig ” is an obsolete command. You must do what the command tells you to solve this problem or execute “ ip addr list ” even if the result changes slightly with those expected when executing “ ifconfig “.
Finally, we want to show you how to find out what’s your IP on a Mac.
As we did in Linux to search for the terminal with a special key command, we have several ways to run the terminal on Mac. For ease, I recommend using the search icon on the top right of the operating system, called “Spotlight“.
Once the search box is opened, type ” Terminal ” and press the ENTER key.
In the terminal, type the command ” ifconfig ” as in the case of Linux. Click ENTER and look at the result. Here you can see the private IPv6 IP address on Mac .
If you want to see the private IPv4 IP address on Mac, what you have to do is go to the ” dock ” (bottom bar) and look for the ” system preferences ” icon .
Next, you will see a system preferences box where you must go to the « Network » icon and click there:
Another window will appear in which you will have to click on ” advanced options ” in the lower right button (although in some versions of Mac they already tell you the IPv4 address right here).
Again another window is superimposed with different tabs such as ” Wi-Fi “, ” TCP / IP “, ” DNS “, ” WINS “, etc. You have to go to ” TCP / IP ” and by clicking there you will see the IPv4 IP of Mac .
And we have finished the way to find out the private IP address v4 and v6 on Windows , Linux and Mac .
It is very important to know how the basic Internet architecture works. Even more if you choose to hire a web host. If you need to hire a dedicated IP for one of your projects, be it web hosting or specific servers, you can ask us and we will be happy to help you.