In one of my post i calculate the subnet and valid host range for class b and with cidr value /16 to /30 this is that page. Class B Network Subnet Masks and possible hosts for each mask with cidr. I know there will some software that has precalculated for this data and this day i find one of them and there is lot of them in the internet and if you look for the networking related software you will lot of them. but we are always looking for that we need to build up our skill first then we will go for this software. First we need to know that for a certain ip address and for certain cidr values we need do the calculation and key thing we will not get any kind software to do the subnet calculation in our ccna exam and in ccna exam we need to do something with our skill and from expertness but when we are in home then we can do this very easily but i recommened build your skills first and then go for shortcut.
There are lot of thing that i know that ip subnet calculator and subnet calculator and alos cidr calculator and freely available. When i search in google for the subnet calculator i see that there is a website about subnet calculator and they offer free to calculate the subnet calculation.
In here i just embed a website for you to see some preview of how you can use subnet calculator to find the subnet mask ; valid host range ; and also the website that view you in this page is also ip converter.
Ip converter you just convert your ip binary to decimal and decimal to binary and also convert the ip in hexadecimal. And i think we all can do this in our paper now for just make sure that the result is 100% valid and thats for you can use this tool and also there are lot of as i mention are free to download. and also you can find so quickly the subnet mask for the specific cidr but i think that i can say a cidr value for you very quickly and i know that its easy for me and i done a lot of practice and you can do the practice to make that you do not need software and we are too fast then from software and thats exactly what we are looking for.
oK so here is a preview of the software power in subnetting