Loopback (loop-back) describes ways of routing electronic signals, digital data streams, or flows of items from their originating facility back to the receiving end of the source without intentional processing or modification. This is primarily a means of testing the transmission or transportation infrastructure.
Example applications:
- Performing transmission tests of access lines from the serving switching center, which usually does not require the assistance of personnel at the served terminal.
- Testing between stations (not necessarily adjacent) where in two lines are used, with the test being done at one station and the two lines interconnected at the distant station. Commonly called loop around when the interconnecting circuit is accessed by dialing.
- A patch cable, applied manually or automatically, remotely or locally, that facilitates a loop-back test.
- A communication channel with only one endpoint. Any message transmitted through such a channel is immediately received by the same channel.
Read more about Loopback: Virtual Network Interface, Network Equipment, Serial Interfaces, Telecommunications, Other Applications