CIDR Masks /17 - /30 Flashcards
1
Q
/17
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 128 mask
- 1 bit on, 7 bits off (1000 0000)
- Block size 128
2
Q
/18
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 192 mask
- 2 bit on, 6 bits off (1100 0000)
- Block size 64
3
Q
/19
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 224 mask
- 3 bit on, 5 bits off (1110 0000)
- Block size 32
4
Q
/20
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 240 mask
- 4 bit on, 4 bits off (1111 0000)
- Block size 16
5
Q
/21
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 228 mask
- 5 bit on, 3 bits off (1111 1000)
- Block size 8
6
Q
/22
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 252 mask
- 6 bit on, 2 bits off (1111 1100)
- Block size 4
7
Q
/23
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 254 mask
- 7 bit on, 2 bits off (1111 1110)
- Block size 2
8
Q
/24
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 255.255.255.0 mask
- Block size 256 (254 hosts)
9
Q
/25
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 128 mask
- 1 bit on, 7 bits off (1000000)
- Block size 128
- Subnets 0, 128
- 2 subnets, 126 hosts each
10
Q
/26
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 192 mask
- 2 bits on, 6 bits off
- Block size 64
- Subnets 0, 64, 128, 192
- 4 subnets, 62 hosts each
11
Q
/27
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 224 mask
- 3 bits on, 5 bits off (11100000)
- Block size 32
- Subnets 0, 32, 64, 96, 128, 160, 192, 224
- 8 subnets, 30 hosts each
12
Q
/28
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 240 mask
- 4 bits on, 4 bits off
- Block size 16
- Subnets 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240
- 16 subnets, 14 hosts each
13
Q
/29
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 248 mask
- 5 bits on, 3 bits off (11111000)
- Block size 8
- Subnets 0, 8 ,16, 24, 32, 40, 48, etc
- 32 subnets, 6 hosts each
14
Q
/30
- mask
- bits on, bits off
- block size
- x subnets, y hosts
A
- 252 mask
- 6 bits on, 2 bits off (11111100)
- Block size 4
- Subnets 0, 4, 8, 12, 16, 20, 24 etc
- 64 subnets, 2 hosts each
