ZyXEL Communications Internet Security Gateway ZyWALL 2 Series User Manual page 566

ZyWALL 2 Series User's Guide
IP Address
IP Address (Binary)
Subnet Mask (Binary)
Subnet Address: 192.168.1.192
Broadcast Address: 192.168.1.255
Example Eight Subnets
Similarly use a 27-bit mask to create 8 subnets (001, 010, 011, 100, 101, 110).
The following table shows class C IP address last octet values for each subnet.
SUBNET SUBNET ADDRESS
1
2
3
4
5
6
7
8
The following table is a summary for class "C" subnet planning.
NO. "BORROWED" HOST BITS
1
2
3
I-6
Chart I-10 Subnet 4
192.168.1.
11000000.10101000.00000001.
11111111.11111111.11111111.
Chart I-11 Eight Subnets
FIRST ADDRESS
0
32
64
96
128
160
192
224
Chart I-12 Class C Subnet Planning
SUBNET MASK
255.255.255.128 (/25)
255.255.255.192 (/26)
255.255.255.224 (/27)
NETWORK NUMBER
Lowest Host ID: 192.168.1.193
Highest Host ID: 192.168.1.254
LAST ADDRESS
1
33
65
97
129
161
193
223
NO. SUBNETS
LAST OCTET BIT VALUE
192
11000000
11000000
BROADCAST ADDRESS
30
62
94
126
158
190
222
254
NO. HOSTS PER SUBNET
2
4
8
31
63
95
127
159
191
223
255
126
62
30
IP Subnetting