Learning IPv4
Private IP Address Range
| Class | Range |
|---|---|
| A | 10.0.0.0/8 |
| B | 172.16.0.0/12 |
| C | 192.168.0.0/16 |
Subnetting Cheatsheet
| Total IPs | 32768 | 16384 | 8192 | 4096 | 2048 | 1024 | 512 | 256 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Usable IPs | 32766 | 16382 | 8190 | 4094 | 2046 | 1022 | 510 | 254 | 126 | 62 | 30 | 14 | 6 | 2 | N/A | N/A |
| Netmask | /17 | /18 | /19 | /20 | /21 | /22 | /23 | /24 | /25 | /26 | /27 | /28 | /29 | /30 | /31 | /32 |
| Octet | 3rd | 3rd | 3rd | 3rd | 3rd | 3rd | 3rd | 3rd | 4th | 4th | 4th | 4th | 4th | 4th | 4th | 4th |
| Subnet | .128 | .192 | .224 | .240 | .248 | .252 | .254 | .255 | .128 | .192 | .224 | .240 | .248 | .252 | .254 | .255 |
| IPv4 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 |
Based off the cheatsheet:
192.168.0.0/24has256IP addresses, one of those addresses is allocated to the Network ID, which is the first IP in the given network and another is allocated to the Broadcast, which is the last IP within the given network. Leaving254usuable IPv4 addresses.
Network ID: 192.168.0.0
Hosts: 192.168.0.1-254
Broadcast: 192.168.0.255
Subnet: 255.255.255.0
next Network ID: 192.168.1.0
192.168.0.0/30has4IP addresses, one of those addresses is allocated to the Network ID, which is the first IP in the given network and another is allocated to the Broadcast, which is the last IP within the given network. Leaving2usuable IPv4 addresses.
Network ID: 192.168.0.0
Hosts: 192.168.0.1-2
Broadcast: 192.168.0.3
Subnet: 255.255.255.252
next Network ID: 192.168.0.4
192.168.0.128/30has4IP addresses, one of those addresses is allocated to the Network ID, which is the first IP in the given network and another is allocated to the Broadcast, which is the last IP within the given network. Leaving2usuable IPv4 addresses.
Network ID: 192.168.0.128
Hosts: 192.168.0.129-130
Broadcast: 192.168.0.131
Subnet: 255.255.255.252
next Network ID: 192.168.0.132
192.168.0.0/20has4096IP addresses, one of those addresses is allocated to the Network ID, which is the first IP in the given network and another is allocated to the Broadcast, which is the last IP within the given network. Leaving4094usuable IPv4 addresses.
Network ID: 192.168.0.0
Hosts: 192.168.0.1-15.254
Broadcast: 192.168.15.255
Subnet: 255.255.240.0
next Network ID: 192.168.16.0