A method includes monitoring, by a first network device, traffic from a customer device, wherein the traffic is to be forwarded via a provider’s network. The nanotube is basically a graphite device which is now subjected to stress causing the electrical characteristics of the nanotube to change according to stress. The first color points comprise weak image texture. The upper mold layer, the lower mold layer and the etch stop layer are then subjected to dry etching to form an opening therein which exposes at least a portion of the surface of the contact plug.