This is a free-text alphanumeric label (dash or underscore allowed, up to 256 characters) that an operator assigns to the coherent optical channel (och-os) on the line side of a pluggable transceiver for easy identification in the management system. It has no effect on the equipment's own operation; it exists purely so a technician scanning a fault list can tell one instance of a och-os facility apart from another. For example, a technician might set this alias to something like 'och-os-RingA-East' so an incoming alarm on this facility immediately identifies which physical link it belongs to.