Special IPv4 addresses
In the IPv4 address space, there are three special network blocks that are reserved for special usage. These special IPv4 addresses are as follows:
- Loopback address
- Test-Net
- Link Local
In this section, we will look at each of their characteristics and use cases.
Loopback address
The loopback range of an address is built into the TCP/IP protocol suite. This range of addresses allows an application running on a host machine to communicate with an application on the same machine. To put it more simply, loopback addresses allow a host operating system to send network traffic to itself.
The network block is reserved for loopback and has the range 127.0.0.1/8
to 127.255.255.254/8
. Therefore, to test the functionality of the TCP/IP protocol suite, you ping any address from the loopback range. Most commonly, network professionals ping the 127.0.0.1
address.
Test-Net
According to RFC 3330
, the block of addresses 192.0.2.0/24
to...