DES-3326S Layer 3 Fast Ethernet Switch User’s Guide
Class E Addresses are reserved for future use. They are not used for node addresses.
The part of the IP address that belongs to the network is the part that is ‘hidden’ by the ‘1’s in the subnet mask. This can be seen below:
•Class A NETWORK.node.node.node
•Class B NETWORK.NETWORK.node.node
•Class C NETWORK.NETWORK.NETWORK.node
For example, the IP address 10.42.73.210 is a Class A address, so the Network part of the address (called the Network Address) is the first octet (10.x.x.x). The node part of the address is the last three octets (x.42.73.210).
To specify the network address for a given IP address, the node part is set to all “0”s. In our example, 10.0.0.0 specifies the network address for 10.42.73.210. When the node part is set to all “1”s, the address specifies a broadcast address. So, 10.255.255.255 is the broadcast address for the network 10.0.0.0.
Subnet Masking
A subnet mask can be applied to an IP address to identify the network and the node parts of the address. A bitwise logical AND operation between the IP address and the subnet mask results in the Network Address.
For example:
00001010.00101010.01001001.11010010 10.42.73.210 Class A IP address
11111111.00000000.00000000.00000000 255.0.0.0 Class A Subnet Mask
00001010.00000000.00000000.00000000 10.0.0.0 Network Address
84 | Switch Management and Operating Concepts |
