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I want to calculate

  1. Network Address
  2. Address Of First Host
  3. Address Of Last Host
  4. Broadcast address

when an IP address of the network is given. is there any standard calculate to solve this question?

I could find the following site supports in solving above question.

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With the IP address alone that is impossible. – NickW Jun 6 '13 at 16:13
@NickW It really isn't. Assuming the network in question was done correctly. – AthomSfere Jun 6 '13 at 16:32
Ok, tell me the starting and ending network numbers of this IP address – NickW Jun 6 '13 at 16:34
@NickW What is your subnet? Assuming / 8 then address, first and last host or for braodcast... – AthomSfere Jun 6 '13 at 17:43
Exactly why I say you can't do it with an IP alone... – NickW Jun 7 '13 at 8:20

1 Answer 1

up vote 2 down vote accepted

This requires a decent understanding of subnetting, and I will give a birds eye view of how to guess-timate.

Your subnet and IP addresses are inverse binary numbers that are in dot-decimal format. (If everything is using standard ranges.

The subnet == 11111111 1111111111 11111111 00000000 in decimal, which means you have 256 IPs available (0 - 255).

Using standard subnetting we can assume with an IP of as a client's IP that:

Our network address should be Our first address (And likely Gateway) is the first address in that range Our Broadcast address is always the last number in the range Our last useable address for clients is the broadcast - 1, or

This really is a very high level, and not perfect explanation as it is decently involved.

For help with the math: Look at how to calculate your address, easily script-able.

Here is a good intro to subnetting as well

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Thanks for your explanation and links. Those were very helpful for me. – Kanishka Dilshan Jun 6 '13 at 19:47

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