I feel stupid asking this, but I have always had a hard time understanding subnets no matter how much I have read on them. I always end up more confused than when I started.<BR><BR>What I do ...

I have an Excel spreadsheet containing IP addresses and subnet masks. I need to derive the subnet of each IP address in the spreadsheet.<BR><BR>Example: IP (column A): 10.1.230.84, Subnet Mask (column ...