Hello, my name is Chris from Gateway Health Plan. I am the firewall administrator for our network and find the Advanced Subnet Calculators very useful at calculating subnet masks. It really saves a bunch of time not having to manually calculate them, you just type in the address range and it will spit it right out at you before you can blink an eye. I also use the network monitoring tool which is very convenient for letting me know when a device goes down or becomes unavailable. It is nice to be alerted right when a device goes down so troubleshooting can begin immediately. This really helps us serve our users in a very effective manner and minimizes down time.