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Subnetting is easy. To implement subnetting, you can create a chart.
Block Size: 128 64 32 16 8 4 2 1
Subnet Mask: 128 192 224 240 248 252 254 255
First Octet: 1 2 3 4 5 6 7 8
Second Octet: 9 10 11 12 13 14 15 16
Third Octet: 17 18 19 20 21 22 23 24
Fourth Octet: 25 26 27 28 29 30 31 32
CIDR stands for Classless Inter-Domain Routing.
/32 = 1 /31 = 2 /30 = 4 /29 = 8 /28 = 16 /27 = 32 /26 = 64 /25 = 128
/24 = 256 /23 = 512 /22 = 1024 /21 = 2048 /20 = 4096 /19 = 8192 /18 = 16384 /17 = 32768
/16 = 65536 /15 = 131072 /14 = 262144 /13 = 524288 /12 = 1048576 /11 = 2097152 /10 = 4194304 /9 = 8388608
/8 = 16777216 /7 = 33554432 /6 = 67108864 /5 = 134217728 /4 = 268435456 /3 = 536870912 /2 = 1073741824 /1 = 2147483648
/0 = 4294967296
These are the total IP addresses for each CIDR block.