Table 137 Subnet 1; Table 138 Subnet 2; Table 139 Subnet 3; Table 140 Subnet 4 - ZyXEL Communications P-660HW-D User Manual

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 (00, 01, 10 and 11). The subnet
mask is 26 bits (11111111.11111111.11111111.11000000) or 255.255.255.192. Each subnet
contains 6 host ID bits, giving 2
all ones is the broadcast address on the subnet).

Table 137 Subnet 1

IP/SUBNET MASK
IP Address
IP Address (Binary)
Subnet Mask (Binary)
Subnet Address: 192.168.1.0
Broadcast Address:
192.168.1.63

Table 138 Subnet 2

IP/SUBNET MASK
IP Address
IP Address (Binary)
Subnet Mask (Binary)
Subnet Address: 192.168.1.64
Broadcast Address: 192.168.1.127

Table 139 Subnet 3

IP/SUBNET MASK
IP Address
IP Address (Binary)
Subnet Mask (Binary)
Subnet Address:
192.168.1.128
Broadcast Address:
192.168.1.191

Table 140 Subnet 4

IP/SUBNET MASK
IP Address
IP Address (Binary)
Subnet Mask (Binary)
Subnet Address:
192.168.1.192
Broadcast Address:
192.168.1.255
P-660HW-D User's Guide
6
-2 or 62 hosts for each subnet (all zeroes is the subnet itself,
NETWORK NUMBER
192.168.1.
11000000.10101000.00000001.
11111111.11111111.11111111.
Lowest Host ID: 192.168.1.1
Highest Host ID: 192.168.1.62
NETWORK NUMBER
192.168.1.
11000000.10101000.00000001.
11111111.11111111.11111111.
Lowest Host ID: 192.168.1.65
Highest Host ID: 192.168.1.126
NETWORK NUMBER
192.168.1.
11000000.10101000.00000001.
11111111.11111111.11111111.
Lowest Host ID: 192.168.1.129
Highest Host ID: 192.168.1.190
NETWORK NUMBER
192.168.1.
11000000.10101000.00000001.
11111111.11111111.11111111.
Lowest Host ID: 192.168.1.193
Highest Host ID: 192.168.1.254
Appendix F IP Subnetting
LAST OCTET BIT
VALUE
0
00000000
11000000
LAST OCTET BIT
VALUE
64
01000000
11000000
LAST OCTET BIT
VALUE
128
10000000
11000000
LAST OCTET BIT VALUE
192
11000000
11000000
303