A walm welcome to you!!!

Let us share something worth that will help all of us to increase our knowledge orientation in the huge and ever expanding world of Networking!

I have created this blog to help each and everyone who visits this blog to get himself acquainted with new technologies, recent developments in the world of technology....

I hope you will help me share my knowledge with you....!!!!

Thursday, March 29, 2012

IP Addressing (Fundamental Concepts & IPv4 Basics)

My come back has been delayed, actually I was unable to keep in touch with my blog for a few weeks.

Anyways, to make it large, let me start with IP Addressing. Now, what is an IP address? If you have gone
through my earlier post titled "OSI, IP Suite & the DoD Model-I (OSI Model)", you must have got a
rough idea about the core concepts of functioning of internet. Again, to revise, if we take a closer look
at the network layer, it describes something called as "logical addressing".

Logical addressing, as the name suggests, describes a process through which addresses are assigned to every host on the network logically and not  physically.

Logical addressing concept is the base on which the process of routing functions. To go into the
depths of this concept, routing is the process of finding, determining and selecting the best path by the
 host to reach another host located generally on another network. Consider two networks- Network A
& Network B. Now Host 1 is located in Network A & Host 2 is located in Network B. If Host 1 is
 trying to reach Host 2, then it is trying to communicate with a host (Host 2) on a different network.
Here, Host 1 will use routing. Routing is done using special networking devices called as routers.

Now, to carry out the process of logical addressing, "IP" is used. IP is an abbrevation for Internet Protocol.
IP is a network layer (Layer 3) protocol in the TCP/IP stack providing routing and logical addressing
standards. IP is one of the most important concepts in the world of networking. Let me first of all explain
you the concept called "IP Packet". An IP Packet is simply a data carrier. When two hosts communicate,
they use IP Packets and these packets are compiled into a specific format.

IP is of two types-IPv4 & IPv6 i.e. Internet Protocol version 4 & version 6.

IPv4 is what we are using since IP was brought into use. You may be knowing concepts called as "bits". Bits, bytes etc. are the units of digital information in computing and telecommunication. Let me show you
some useful conversions

If you have gone through the above conversion chart, then please note that there is a difference between
Kilobits (kb) & Kilobytes (KB) even though I haven't mentioned it in the above chart. The difference is that
1kb=1000 bits while 1KB= 1024 bytes. Similarly, 1mb=1000000 bits while 1MB= 1024 kilobytes or 1048576 bytes or 8388608 bits.

I hope you have got the idea about the conversions. It is important to understand these conversions since they are useful in carrying out important IP calculations. 

Now, there are heaps of differences in IPv4 & IPv6 (and obviously, there must be!). IPv4 is denoted in a 
32 bit format divided into 4 parts. For example, is an IPv4 address. If you convert this address into a binary format, you will arrive at 11000000.10101000.01100100.01100100. You can take a
closer look at the above binary format, then you will see that there are 32 bits divided into 4 blocks of 8 bits each. 

Since we call them "IP Addresses", they are divided into particular blocks and each block called as an "IP
Class". Technically, we should say that IP space can be divided into five classes. IP Classes relate
 to the type of business or network that the computer is associated with. Since the IP address space is divided into different classes, this methodology is termed as "classful network.

Every class in this classful network includes an IP Range. IP Range denotes the number of IP addresses
 that a particular class can hold. Here it goes-

Classes D is reserved for multicasting & Class E is reserved for experimental users.

If you have a closer look at the above table, you will notice that the address is absent. So where has it gone? is known as the loopback address. A loopback address or interface is one where any traffic that is sent to this interface is received by the same interface. The loopback address range goes from to If you are using a web server, you can point your browser to http://localhost/ or, and you will notice that you have accessed the computer's own website.

Packets sent from a loopback interface (being the source address) in an IP network can cause a hell lot of problems.These are called as the martian packets and the source addresses for these are collectively called as bogons. 

To drift a bit away from the IP concept, let me narrate the concept of pinging. Pinging is a test that may 
 be executed from a computer located in a network to test the reachability to another host located on 
either the same or different network. PING stands for Packet Internet Gopher. If you want to "ping" another host whose IP  or web address is known to you, then simply open the Command Prompt and 
type ping x.x.x.x where "x"s stand for the digits of an IP address. 

Now, to finish off with the basics of IPv4, let me tell you that since IPv4 is a 32-bit address, the number of addresses will be 232 which will be 4294967296 available addresses.

In the next post, I will be discussing about IPv6, which is one of the most revolutionary concept in the field of networking and the Internet.


  1. hey first its gud 2 have c u updating ur blog after a longgggggggggggg time.......d post is indeed complex....:( will read it once more for a better understanding.......u plan 2 write somethng more about internet security measures in future?????

  2. ya, its indeed a bit complex, actually it is easily understood by people who are from networking field. anyways, u will get it after u read it once more. about internet security...i will write it in a couple of days...

  3. k boss...... :):)

  4. Its VERY complex. Having the right proxy service can help out a lot though. Great post.

    1. Thank you Mike for your comment. Absolutely, what you are saying is right. Please share your knowledge here, I, personally will benifit a lot....