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IP Subnetting Made Easy (read very good but I have not been able to match calculation of tools yet) - http://www.techrepublic.com/article/ip-subnetting-made-easy/6089187
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IP Subnetting Made Easy (read very good but I have not been able to match calculation of tools yet) - http://www.techrepublic.com/article/ip-subnetting-made-easy/6089187
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