A DC-powered device (200) configured to receive DC power from an external power sourcing equipment (202) and to exchange operational data with the power sourcing equipment, the DC-powered device comprising an interface unit (206) comprising at least one connection unit (208) configured to receive the DC power from the power sourcing equipment and to exchange operational data with the power sourcing equipment, a data processing unit (214) connected to the interface unit and configured to compare the exchanged operational data with prestored allowed operational template data and to generate and store, in a storage unit (216), log data pertaining to unallowed operational data, the unallowed operational data being any exchanged operational data that does not correspond to the prestored allowed operational template data, and an operational unit (218), configured to execute operational instructions pertaining to that exchanged operational data corresponding to the prestored allowed operational template data.