What is an IP Address?

by Networking Guy


An IP Address (Internet Protocol) is a series of numbers assigned to any kind of electronic hardware that is connected to a network or the internet. Why does an electronic device need an IP address you ask?

First of all I have to give you an example of what an IP Address looks like.

234.123.12.1

That is a random IP Address and as you can see, it is formed by four series of numbers separated by full stops. Each of those can be a number between 0 and 255. This kind of numbering is used because the IP address itself is a binary code, which is encoded using 8 bits. This limits the numbers to that interval, but considering that there are hundreds of millions of options, you really don’t need more numbers(until recently we began running out of IP addresses).

There is classful and classless addressing for IP addresses.

Classful Network Architecture
Class First octet(binary) Range of first octet Network ID Host ID Network Count Address Count
A 0XXXXXXX 0 – 127 a b.c.d 128 16,777,214
B 10XXXXXX 128 – 191 a.b c.d 16,384 65,534
C 110XXXXX 192 – 223 a.b.c d 2,097,152 254

The first number in the IP Address indicates the type of IP address, external, internal, and so on (When we refer to private addressing in company networks). This is useful because you can connect to the internet using a router, which distributes internal IP Addresses to the computers connected to it. The actual problem is that the router is assigned an IP Address (usually by the ISP or Internet Service Provider) and it cannot assign the same address to the computers. So, for example, your computer will have an IP Address looking like this: 10.120.130.1 and your friend’s computer will have an address ending in 2.

The IP Address that your computer has if it is directly connected to the internet is assigned by the Internet Service Provider, as mentioned above, from a specific class of addresses that have been made available to the ISP by the IANA or the Internet Assigned Numbers Authority. So, you are not actually getting a random IP Address, you get one from a specific set assigned to be used by your ISP.

Basically, the IP Address is like the street and house number of your computer. For example, when you access an internet resource (website, in general) your computer tells the site at what address to send the requested information. This process takes place in a very short amount of time, depending on the speed of your connection. Note that even though websites are hosted with regard to IP addresses, DNS server takes care of mapping domain names to IP addresses. This helps us to use easy-to-remember names like google.com instead of the IP addresses associated with each website.

Here are a couple of other things you should know about the IP Address:

  • Using an internet application you can find out where someone lives based entirely on the IP Address (Geo targeting, Remember seeing those ad’s which mentions places you are located at?)
  • Using an IP Address you can access your home computer from any other computer around the world (You need a static IP though to get connected every time using the same IP address)
  • There are some service providers that constantly assign a new IP Address to your computer(Dynamic IP). This is an added advantage in some cases where you really do not want to have the same IP associated with your computer
  • Yes, you need an IP Address when you play online games or even those in the Local Area Network (Direct connections are made using your unique IP address)
  • There is no chance that two externally assigned addresses (IP address) will ever be the same. Remember that the ISP will keep track of the IP logs and you cannot deny any activity that happens through your address.
  • You can change your IP Address whenever you want using a specially designed program (you will find lot’s of IP hiding softwares out there), but when you logout and log back in you will have the same address as before.

An IP Address can be used for a lot of purposes besides the ones mentioned above. For example, your IP Address can be used to download information from the internet (through services which white-lists certain IP’s only), you can send emails or messages to an IP Address alone (email mapping takes place and you need an SMTP server to send and receive mails) and you can also make your computer anonymous with one of those IP Address changing programs that renew it every 2 seconds (the amount of time varies depending on the pogram).

Basically, the IP Address is the basis of the Internet today. If no one would have come up with this type of numbering system we wouldn’t have been able to connect more than a couple of hundred computers in the same network and the internet would have been limited to local area networks on a slightly larger scale. I know that I said that the IP Address is used in Local Area Networks as well, but you can connect to such a network with a smaller range of IP Addresses (Reserved IP’s for intra networks). Your computer could have been assigned a number from 0 to 255. So, the maximum number of computers that could work in the same network at the same time would be 256. Normally 0 and 255 are not used. Take the case of 127.0.0.0 which is the loop back address and 255.255.255.255 which is the broadcast address.

There are several versions of IP Addresses. Simply put, they are evolutions of the older types, but you will probably be confused, since the older ones look exactly the same. Well, yes they do, but the IPV4 has less actual numbers than the IPV6 for example. To make it even simpler, the difference between these two versions is the actual encryption method. One uses 128 bit, the other 64. Then there are differences like the number of addresses possible, security and so on. Refer to the figure below

ipv4 and ipv6

So, as you can see, the IP Address is the basis of electronic data transfer and communication and it also provides with certain safety levels (IPSec) in specific situations.  I have been asked a couple of questions regarding the IP Address and the most common was if you can assign yourself an IP Address. The answer is that it depends on a lot of aspects. There are a couple of ways to change your IP Address automatically, but it is only temporary and your computer still has a unique IP Address each time you turn it on again. If you want another IP Address to be assigned to your computer you can call the ISP and ask for this. If you are lucky they will change it on the spot. Most of the time all you need to do is restart the modem and you will get a new IP address. Most ISP’s will assign dynamic IP’s only and if you want a static IP (In a network or using SSL), then you may need to request it separately.

An IP Address is very useful when you want to play online games, as mentioned earlier. There are some multiplayer modes that allow you to connect to other players accessing and connecting to their IP Address. Those are currently considered outdated, but I believe that they are the most stable connections possible. I know my friend who is a hardcore football gamer who uses the IP address in his game application to connect with another person and play games over the internet.

IP addressing will see a radical change in the coming years. The transition from IPV4 to IPV6 is taking place. There might come a situation when IPv6 may be insufficient which will definitely take some time.