Definition - What does Loopback Test mean?
A loopback test is the process of sending digital data streams from a source back to the same point without any intentional modifications. It’s generally performed to determine whether a device works properly and whether there are failing nodes in a network.
Techopedia explains Loopback Test
Loopback testing is a diagnostic procedure in which a signal is transmitted and returned back to the same sending device after passing through all or a portion of a network to test transportation or transportation infrastructure. A comparison of the returned signal with the transmitted signal conveys the integrity of the transmission path. A loop plug, called a wrap plug, is inserted into the port of a communication device to facilitate the loopback test.
Loopback tests can readily be used to test computer serial ports and radio interfaces, and are one of the easiest ways to verify RS-232 communications.
Interfaces such as aggregated Ethernet, gigabit Ethernet, fast Ethernet, etc. can also be configured to execute a loopback test to verify circuit connectivity. The loopback test isolates circuit segments so that they can be tested separately.