IP Addressing

Zainub Wahid Classes, IANA, Internet Protocol Classes, IP, IP Addresses, IP Addressing, Subnet Mask

When you send  a query to Google, it replies you back. Have you ever wondered and tried to figure out that how Google replies you? How Google knows that its only you who want reply? Why the reply by Google is not sent to all the devices connected in network? How Google figures it out which reply to be sent to which device only? OK, leave Google, Let’s suppose your are in your office and you want to communicate with only one PC, but how do router figures out that where to send the query? Why the router in your office don’t send reply to all the devices connected to that network? Aren’t you curious how communication is happening on Internet? The one word answers to all these questions and that one word is “IP Addressing”.

IANA(Internet Assigned Numbers Authority) is responsible for global coordination of the Internet Protocol addressing systems, as well as the Autonomous System Numbers used for routing Internet traffic. Users are assigned IP Addresses by Internet Service Providers (ISPs). ISPs obtain allocations of IP addresses from Local Internet Registry (LIR) or National Internet Registry (NIR).

Internet Protocol Addressing abbreviated as IP Addressing is a 32-bit address assigned to every device connected to Internet. In Internet world, your device is known by this IP Address, not by your name. This 32-bit Address is divided into 4 partitions by a dot adn can be called as 4 octets. Every 8 bits (one part of partition, one octet) ranges from 0-255 in decimal. This range can be calculated as:

Minimum 8-bit: 00000000 in binary = 0 in decimal
Maximum 8-bit: 11111111 in binary = 255 in decimal

So, now for 32-bit, IP addresses ranges from:
Minimum: 00000000.00000000.00000000.00000000 = 0.0.0.0
Maximum: 11111111.11111111.11111111.11111111 = 255.255.255.255

From the above calculations, we can say that no part of the 32-bit IP address can be greater than 255 or lower than 0. Few simple examples of IP Addresses are:

– 1.1.56.1
– 150.154.76.6
– 192.168.0.4
– 228.54.77.121

In your PC you can view the IP addresses in decimal and they must be similar to above examples. But router or any device cannot read in decimal so, they convert it to binary and then use these addresses for further communication.

So, now depending on the first 8-bits and their range, IPs are divided into 5 classes. Before explaining these classes, you must know how of Address, Subnet, Subnet Mask, Network and Host bits, Interface.

Address: The unique number ID assigned to one host or interface in a network.
Subnet: A portion of a network that shares a particular subnet address.
Subnet Mask: A 32-bit combination used to describe which portion of an address refers to the subnet and which part refers to the host.
Network and Host Address: The network address is used to identify the network and is common to all the devices attached to that network. Host Address is the remaining portion of IP address that is specific for every device and is used to identify that specific device.
Interface: A network connection.

Now, lets study the classes and IP addressing deeply.

12.PNG

1- Class A:

Actual Range: 0-127 but this class is used for commercial purposes by commercial purposes mean, IPs ranging in that class are sold at some fixed prices. But, 0 is fixed for current network i.e. host to neighbor connection. And, 127 is fixed for localhost i.e. loopback IP.

So, we can say that IP addresses starting with 0 are fixed for neighbor connection and IPs starting with 127 are fixed for localhost devices. IP Addresses starting with 0 means “0.X.X.X” where, X can be any value from 0-255. And IP Addresses starting from 127 means “127.X.X.X”. Therefore, its range in table is written as 1-126. Now if you convert 1-126 in binary, you will get “0” as its most significant bit. Converting the First octet into binary and then checking its 1st Order High octet bit will make easier to find the class of any given IP address for device. For example, lets convert 1 to binary. You will get “00000001” and now convert 126 into binary and you will get “011111110”. These are the minimum and maximum numbers of class A range.

Now lets discuss Network and Host ID. As described earlier Network address is the fixed address of the network. For class A, first octet tells the network Address and therefore, its subnet mask is 255.0.0.0. Subnet masks tells, first octet will be the network address and remaining three octets are Host IDs. For example, 122.220.0.199 is an IP Address of Class A. “122” shows its from Class A and class A shows its subnet mask will be 255.0.0.0. And Network Address of this IP will be 122.0.0.0 and Host Address will be 0.220.0.199.

2- Class B:

The range of class B is 128-191. This means, if first octet of IP Address is from 128-191 then that IP belongs to Class B. The first bits of first octet will be “10”. For example, lets convert 128 to binary and you will get “10000000”. If you convert 191 to binary, you will get “10111111”. Subnet Mask is 255.255.0.0 hence, first two octets will tell the Network Address. So, for example, if we have an IP 140.70.199.0, then 140.70.0.0 shows the Network address.

3- Class C:

The range of class C is 192-223. This means, if first octet of IP Address is from 192-223 then that IP belongs to Class C. The first bits of first octet will be “110”. For example, lets convert 192 to binary and you will get “11000000”. If you convert 223 to binary, you will get “11011111”. The minimum IP Address will be “192.0.0.0” and the maximum can be “223.255.255.255”. Subnet Mask is 255.255.255.0 hence, first two octets will tell the Network Address. So, for example, if we have an IP 200.70.199.0, then 200.70.0.0 shows the Network address.

4- Class D:

All the above mentioned classes (Class A- Class C) are for commercial purposes. But the Class D is different from them. Class D is used for multicasting purposes and IPs of this class are reserved for special use. The range of class D is 224-239 and the first bits of first octet should be “1110”. For example if you convert 224 to binary, you will get “11100000” and if you convert 239 to binary, you will get “11101111”.

You can consider this class as color of number plates reserved for government. For example in Pakistan, green colored Number plates are reserved for Government cars and such numbers are not sold to local private cars. Similarly, the IPs of this class are reserved and are not sold.

5- Class E:

The range of this class is 240-255. The first bits of first octet should be “1111”. For example if you convert 240 to binary, you will get “11110000” and if you convert 255 to binary, you will get “11111111”.

This class is also not for commercial purposes. The IPs of this class are reserved for testing purposes and are assigned to labs or projects for testing on demand.

13788-3-00 (1).gif

All of this must have left you scratching your head probably. Don’t worry, you will learn everything soon! I hope, this will be helpful for you!

Please comment, if I missed anything or misstated anything.

Thanks!

 

72 thoughts on “IP Addressing”

  1. Pingback: OSI Reference Model | Zainub Wahid
  2. Pingback: Subnetting | Zainub Wahid

  3. My partner and I stumbled over here different web address and thought I might as well check things out.
    I like what I see so now i’m following you.
    Look forward to looking at your web page for a second time.

    Liked by 1 person

    Reply

  4. Hello there, I do think your site might be having internet browser compatibility issues.
    When I take a look at your web site in Safari,
    it looks fine however when opening in Internet Explorer, it’s got some
    overlapping issues. I just wanted to provide you with a quick
    heads up! Aside from that, fantastic blog!

    Liked by 1 person

    Reply

  6. certainly like your web site however you need to check the
    spelling on quite a few of your posts. Several of them are rife with spelling
    problems and I in finding it very troublesome to inform the reality however I’ll definitely come back again.

    Liked by 1 person

    Reply

  8. I am extremely impressed with your writing skills and also with the layout on your blog.

    Is this a paid theme or did you customize it yourself?
    Anyway keep up the excellent quality writing, it is rare to see a great blog like this
    one nowadays.

    Liked by 1 person

    Reply

  18. My partner and I absolutely love your blog and find a lot of your post’s to be just what
    I’m looking for. Do you offer guest writers to write
    content for yourself? I wouldn’t mind composing a post or
    elaborating on a number of the subjects you write about here.
    Again, awesome weblog!

    Liked by 1 person

    Reply

  21. Hmm it appears like your site ate my first comment (it was extremely long) so I guess I’ll just sum it up what I wrote and say,
    I’m thoroughly enjoying your blog. I too am an aspiring blog writer but I’m still new to
    the whole thing. Do you have any recommendations
    for rookie blog writers? I’d really appreciate it.

    Liked by 1 person

    Reply

  22. Very good blog! Do you have any tips for aspiring writers?
    I’m planning to start my own blog soon but I’m a little lost on everything.
    Would you advise starting with a free platform like WordPress or go for a paid option? There are so many choices out there that I’m completely confused
    .. Any ideas? Appreciate it!

    Liked by 1 person

    Reply

    • Start with free platform like WordPress. Then, if you think you can continue, then go for paid option after having enough traffic. Start with the topic you like the most and on which you can write like explaining to a layman. Further, I am available to help you out. You can contact me via “Contact” page.
      Thank you for commenting.

      Like

      Reply

  25. An intriguing discussion is worth comment. I do
    believe that you should publish more about this subject matter,
    it might not be a taboo subject but usually people don’t discuss these issues.

    To the next! Many thanks!!

    Liked by 1 person

    Reply

  26. Hmm is anyone else encountering problems with the pictures on this blog loading?
    I’m trying to determine if its a problem on my end
    or if it’s the blog. Any suggestions would be greatly
    appreciated.

    Like

    Reply

  28. We absolutely love your blog and find a lot of your post’s to be
    what precisely I’m looking for. can you offer guest writers to write content for you personally?
    I wouldn’t mind creating a post or elaborating on a lot of the subjects you write concerning here.

    Again, awesome web site!

    Liked by 1 person

    Reply

  29. I do believe all of the concepts you’ve introduced on your post.
    They’re really convincing and can certainly work.
    Nonetheless, the posts are very short for newbies.
    May you please prolong them a little from subsequent time?
    Thanks for the post.

    Like

    Reply

  33. Superb blog you have here but I was wondering if you knew of any
    forums that cover the same topics talked about here?
    I’d really love to be a part of online community where I
    can get opinions from other knowledgeable individuals that share
    the same interest. If you have any recommendations, please let me know.
    Thanks!

    Like

    Reply

  34. I blog quite often and I truly appreciate your information. The
    article has truly peaked my interest. I’m going to bookmark your blog and keep checking
    for new information about once per week. I subscribed to your RSS feed
    as well.

    Like

    Reply

  35. Asking questions are in fact nice thing if you are not understanding
    anything entirely, except this piece of writing presents fastidious understanding even.

    Like

    Reply

  36. Hey there just wanted to give you a quick heads up and let you know a few of
    the images aren’t loading properly. I’m not sure why but I think its a linking issue.
    I’ve tried it in two different web browsers and
    both show the same outcome.

    Like

    Reply

  37. Heya this is kinda of off topic but I was wanting to know if blogs
    use WYSIWYG editors or if you have to manually code with HTML.
    I’m starting a blog soon but have no coding experience so
    I wanted to get guidance from someone with experience.
    Any help would be enormously appreciated!

    Like

    Reply

  38. I’ll right away clutch your rss feed as I
    can not find your email subscription link or newsletter service.
    Do you’ve any? Please let me realize in order that I may subscribe.
    Thanks.

    Like

    Reply

  40. I think what you said made a great deal of sense. But, what about this?
    what if you composed a catchier title? I ain’t suggesting your information isn’t good, however suppose you added a headline that grabbed people’s attention? I mean IP
    Addressing | Zainub Wahid is kinda boring.
    You should look at Yahoo’s front page and note how
    they write post headlines to grab viewers interested. You might try adding a video or a pic or two to grab people
    excited about everything’ve written. Just my opinion,
    it could bring your posts a little livelier.

    Like

    Reply

  43. Hmm it looks like your blog ate my first comment (it was super long) so I guess
    I’ll just sum it up what I submitted and say, I’m thoroughly enjoying your blog.
    I too am an aspiring blog blogger but I’m
    still new to everything. Do you have any tips for
    inexperienced blog writers? I’d really appreciate it.

    Like

    Reply

  50. Hi! This is my first visit to your blog! We are a group
    of volunteers and starting a new project in a community in the same
    niche. Your blog provided us beneficial information to work on.
    You have done a wonderful job!

    Like

    Reply

Leave a reply to link Cancel reply