Here's a simple and easy method of subnetting Class C networks using a graphical chart. It works for variable length subnetting (VLSM). No difficult binary calculations to do! Just to let you know, there is NO magic shortcut to learning subnetting. Unfortunately, It takes time and practice and this method is the easiest to learn based on my 15 years of teaching subnetting. The worksheets are available for download from the Subnetting page of TelecomWorld 101:
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