A mounting apparatus includes a frame, a resilient grounding piece and a fastener both made of conducting material. User marks are used to determine the visibility of the elements at the various hierarchical levels in a hierarchical directory structure of a database. The tag member is provided at a higher position than the upper end part of the chassis, and a distance from the outer cover can be set optionally. The estimated symbols are remodulated and the channel parameter is re-estimated. The information device can be adapted to send a request for the content from the first content distribution node utilizing an Internet Protocol address of the content distribution node.