PoE requires sufficient power from the network, the switch, and the injector. A Network Administrator will ensure uninterrupted power to the device by evaluating the network, and selecting the correct injector and connector. The network setup must be tested by a qualified cabling technician to confirm compliance with the ANSI/TIA 568.2-D standard. The testing prevents unbalanced resistances in the cabling usage, which may cause data bit errors or a breakdown in consistent power delivery to the device.