Contoh :
172.16.0.0/23
1. Netmask :
11111111.11111111.11111110.00000000
255.255.254.0
2. Jumlah Blok subnet
256 - netmask = 256-254 = 2 {0,2,4,6,8 ....... 254}
3. Jumlah subnet = 2^7 = 128 subnet
4. Jumlah Host Per subnet = 2^9 = 512 host Per subnet
5. Jumlah Host Per subnet Valid = (2^9)-2 = 510 Valid
6. ip address sesuai subnet:
subnet 1:
network : 172.16.0.0
ip 1 : 172.16.0.1
ip end : 172.16.1.254
ip bc : 172.16.1.255
subnet 2:
network : 172.16.2.0
ip 1 : 172.16.2.1
ip end : 172.16.3.254
ip bc : 172.16.3.255
subnet 3
network : 172.16.4.0
ip 1 : 172.16.4.1
ip end : 172.16.5.254
ip bc : 172.16.5.255 Tuliskan 22 subnet ke depan
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172.16.0.0/22
netmask = 255.255.252.0
berapa subnet: 11111111.11111111.11111100.00000000
2^6 = 64 subnet
berapa host per subnet: 2^10 = 1024
berapa host per subnet valid = 1022
blok subnet : 256-252 = 4 {0,4,8,......252}
ip address:
subnet 1:
172.16.0.0
172.16.0.1
172.16.3.254
172.16.3.255
subnet 2:
172.16.4.0
172.16.4.1
172.16.7.254
172.16.7.255
subnet 3:
172.16.8.0
172.16.8.1
172.16.11.254
172.16.11.255