Why Loopback Addresses Can't Be Used As Source Address Inside Packet?

Vishv Patel asked:

We Know That We Ping Localhost, means it can be used as Destination Address,
Why Loopback Addresses Can’t Be Used As Source Address Inside Packet ??

My answer:

It can be used as the source address, and in fact it is the source address when you pinged localhost!

Network traffic to/from localhost is the same as any other network traffic except that it never leaves the host. The localhost address is both source and destination address.

View the full question and any other answers on Server Fault.

Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.