We are doing the subnetting section in my CCNA course, plus I have read the various tutorials on AO(very good by the way). I am wondering if you guys have any tips or tricks that you use to make things easier? I am starting to get a grasp of it, but truly is a pain in the butt. Also, are there any calculators online that you guys think are really good? I have found a couple of them, but I am looking for any that you find are well done. Thanks for any help you could give.