ZyXEL Communications Dimension ES-3148, Руководство пользователя

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Dimension ES-3148 User’s Guide
Appendix B IP Subnetting 271
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 86 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 87 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 88 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