It is provided a polarization-independent optical isolator without depending on the polarized wave of the light being input to the waveguide-type optical isolator, in particular, it is able to completely isolate the propagating light of the backward direction. This composition is especially suitable for baby shampoos which are not irritating. The second set of MAC addresses corresponds to devices with wired connections to the network. The bus registers and the serializingdeserializing circuitry can be provided along signal paths that require additional latency. A start time and an end time of the past target period are the same as the start time and the end time of a future target period. For example, the methodology of the present invention therefore improves on prior art devices by eliminating bonded electrical connections and wires that are traditionally located in the plasma environment and which require passage through the wall of the plasma processing chamber to connect to external monitoring and measuring equipment.