what is routing loopback in atm

Routing loopback in Asynchronous Transfer Mode (ATM) refers to a technical mechanism for testing the communication infrastructure. It involves routing electronic signals or digital data streams back to their source without processing or modification. This is primarily a diagnostic aid to verify the functionality of physical connections. The loopback can be configured as local (to the driver) or remote (to the network) and can operate at various levels, such as the ATM cell or AAL PDU layers.