09 September 2008

Subnet Calculator


One of the biggest challenges to design your local area network and for taking the CCNA exam is calculating subnets.
Actually to calculate subnets is quite easy but it can be confusing for networking newbies. And luckily there are many tools out there that can help us in this problem.

One of the tools is Boson Subnet Calculator, you can download this tool for free from Boson. This thing is very handy, it can calculate subnets, find out which subnet an address belongs to, do a wildcard checking, and have a Decimal IP Calculator.

 
 The only thing you need to do to find what addresses belong to a subnet is just insert the IP address of a computer to the Host IP and slide the Mask bit to match your subnet mask.
As the above picture, I typed in 172.16.10.5 and subnet mask of 255.255.248.0. Immediately I know what addresses for that subnet, you can see them at the Current Host Range.
This tool also valuable to learn subnetting since it shows how it calculates the subnet, recommended for companion to pass CCNA exam.
Too bad you can't use this at the CCNA exam.