Any traffic that a computer program sends on the loopback network is addressed to the same computer. Juniper Networks describes some of the corresponding change this way: вЂњMost IP implementations support a loopback interface (lo0) to represent the loopback facility. The syntax of the new loopback address in IPv6 is simpler: it's ::1. In the old IPv4 system, the loopback address was 127.0. In recent years, the Internet Protocol system has been retrenched to allow for a greater number of IP addresses. The loopback address also looks different in IPv4 than it does in IPv6. Different Loopback Addresses for IPv4 and IPv6 Domain Addressing Systems The autonomous system, as its own internal network, has its own protocols, to which a loopback address test can be a remedy for certain problems with network verification. The loopback address is also useful in Border Gateway Protocol scenarios that connect routers through inter-domain routing between autonomous systems. Other kinds of testing look at how routers are set up and how they talk to each other, and what can be done to evaluate the functionality of a specific part of a network. For example, a paperclip test will utilize terminal emulator application methodology to verify some type of network connectivity. The loopback interface refers to the overall system by which network engineers can self-reference a device, or вЂњpingвЂќ a device by sending its data packets back to itself.ДЄ loopback interface helps to solve some router problems and implement some kinds of testing.

The loopback address is a vital component of what IT experts call a loopback interface. Techopedia Explains Loopback Address The Loopback Interface

Ping loopback