Easy Way To Remembering Class C Subnetting

What do we should know about class C subnetting (CIDR)? Remembering this will make you easy to solve your problem on exam even on your work. I think you don't need to count everytime you need, just placed this into your mind.

/25 What do we know about a /25?
128 mask
1 bit on and 7 bits off (10000000)
Block size of 128
Subnets 0 and 128
2 subnets, each with 126 hosts

/26 What do we know about a /26?
192 mask
2 bits on and 6 bits off (11000000)
Block size of 64
Subnets 0, 64, 128, 192
4 subnets, each with 62 hosts

/27 What do we know about a /27?
224 mask
3 bits on and 5 bits off (11100000)
Block size of 32
Subnets 0, 32, 64, 96, 128, 160, 192, 224
8 subnets, each with 30 hosts

/28 What do we know about a /28?
240 mask
4 bits on and 4 bits off
Block size of 16
Subnets 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240
16 subnets, each with 14 hosts

/29 What do we know about a /29?
248 mask
5 bits on and 3 bits off
Block size of 8
Subnets 0, 8, 16, 24, 32, 40, 48, etc.
32 subnets, each with 6 hosts

/30 What do we know about a /30?
252 mask
6 bits on and 2 bits off
Block size of 4
Subnets 0, 4, 8, 12, 16, 20, 24, etc.
64 subnets, each with 2 hosts

Easy, right?
Just need time to placed it all into your mind. Print it out and paste on your wall where everytime you can see it.
Happy!

Silahkan tulis komentar, pertanyaan, kritik dan saran anda mengenai blog saya di bawah ini bebas apa saja asalkan sopan. Terima kasih atas kunjungan dan komentar anda. Conversion Conversion Emoticon Emoticon

Thanks for your comment