A single-photon absorption all-optical modulator, systems employing the same, and methods of making and using the same. The cleaning brush removes the charged particles from an object by attracting the charged particles having positive and negative polarity. The mounting lug for the window mill can also be non-metallic. A rotation restrainer is provided for restraining rotation of the filter cleaning unit when the filter cleaning unit reaches a topmost position. During address resolution, the server will resolve a received label into the network address associated with the label as defined by the first accessed address-table which contains the label.