Table 2-4 Reserved IP addresses
Address What it represents Where can it be used
Network address of all 0s Represents “this network”. For example 0.0.0.120 For sending broadcast messages to the network.
Network address of all 1s Represents “all networks”. For sending broadcast messages to all networks.
Node address of all 0s Represents a network address or all hosts in the network. Example 10.0.0.0 or 172.16.0.0 Routers route traffic based on network address.
Node address of all 1s Represents all hosts in a network. Also called the broadcast address. Example 172.16.255.255 or 192.168.10.255 Used to send broadcasts to all hosts in a network.
Entire address of 0s Represents “any network”. Used by routers to designate the default route.
Entire IP set to all 1s. Represents all hosts in network. Used to send broadcast messages
127.0.0.1 Represents the loopback address which is essentially the host itself To send traffic from the host to itself. If you want to connect to a webserver running on the host itself, you will use this address in the browser.