Abstract: A first network device is connectable via electrical lines to a power supply and to other subscribers of a network for transmitting audio and/or image information. It has an input terminal connectable to the power supply, an output terminal connectable to a second network device, and signals and operating voltage are transmitted via the terminals using four layers. Equipment processes the signals received via the lines and the operating voltage in the first network device by receiving and/or retrieving or processing information relating to a maximally available PoE supply input on the input and receiving, or retrieving and or processing information relating to a power intake required at least by the second network device received and/or retrieved and/or further processed by the second network device. A tester is connected to the equipment for checking whether the supply input at the input is sufficient for the first and second network devices.

Abstract: The invention relates, inter alia, to a network device (10) which can be connected via electrical lines (15, 16) to other subscribers (18a, 18b, 12, 13) of a network (42), in particular a real-time intercom network (42), for transmitting audio and/or image information, wherein the network device (10) comprises at least one input-side terminal (22a) for connection to a power supply source (11) and at least one output-side terminal (22b) for connection to at least one second network device (12), wherein signals and operating voltage (PoE) can be transmitted via the terminals, using at least the following four layers (32, 33, 34, 35): a) PTP layer (precision time protocol), b) ethernet layer, c) data and/or information layer, d) PoE (power over ethernet) layer.

Abstract: The invention relates, inter alia, to a network device (10) which can be connected via electrical lines (15, 16) to other subscribers (18a, 18b, 12, 13) of a network (42), in particular a real-time intercom network (42), for transmitting audio and/or image information, wherein the network device (10) comprises at least one input-side terminal (22a) for connection to a power supply source (11) and at least one output-side terminal (22b) for connection to at least one second network device (12), wherein signals and operating voltage (PoE) can be transmitted via the terminals, using at least the following four layers (32, 33, 34, 35): a) PTP layer (precision time protocol), b) ethernet layer, c) data and/or information layer, d) PoE (power over ethernet) layer.