![background image](/i/zyxel/145144/zyxel-p-2000w-ee/h/zyxel-p-2000w-ee-109.png)
Prestige 2000W User’s Guide
Appendix B IP Subnetting
109
Example: Four Subnets
The above example illustrated using a 25-bit subnet mask to divide a class “C” address space
into two subnets. Similarly to divide a class “C” address into four subnets, you need to
“borrow” two host ID bits to give four possible combinations of 00, 01, 10 and 11. The subnet
mask is 26 bits (11111111.11111111.11111111.
11
000000) or 255.255.255.192. Each subnet
contains 6 host ID bits, giving 2
6
-2 or 62 hosts for each subnet (all 0’s is the subnet itself, all
1’s is the broadcast address on the subnet).
Table 34
Subnet 1
NETWORK NUMBER
LAST OCTET BIT
VALUE
IP Address
192.168.1.
0
IP Address (Binary)
11000000.10101000.00000001.
00
000000
Subnet Mask (Binary)
11111111.11111111.11111111.
11
000000
Subnet Address: 192.168.1.0
Lowest Host ID: 192.168.1.1
Broadcast Address:
192.168.1.63
Highest Host ID: 192.168.1.62
Table 35
Subnet 2
NETWORK NUMBER
LAST OCTET BIT
VALUE
IP Address
192.168.1.
64
IP Address (Binary)
11000000.10101000.00000001.
01
000000
Subnet Mask (Binary)
11111111.11111111.11111111.
11
000000
Subnet Address: 192.168.1.64
Lowest Host ID: 192.168.1.65
Broadcast Address: 192.168.1.127
Highest Host ID: 192.168.1.126
Table 36
Subnet 3
NETWORK NUMBER
LAST OCTET BIT
VALUE
IP Address
192.168.1.
128
IP Address (Binary)
11000000.10101000.00000001.
10
000000
Subnet Mask (Binary)
11111111.11111111.11111111.
11
000000
Subnet Address:
192.168.1.128
Lowest Host ID: 192.168.1.129
Broadcast Address:
192.168.1.191
Highest Host ID: 192.168.1.190