The present invention includes a first laser light source mounted to a towing vehicle and oriented to direct a first laser light beam towards a trailer to impinge on a first marker spot located on a hitch coupler mounted to the trailer. With this configuration, the space in which powder toner is present is isolated from the space outside the isolation wall. The stop defines a curvilinear abutment surface adapted to extend into an open manhole and abut a perimeter portion thereof upon the lower support surface being positioned adjacent to the manhole. The relay server, which has a converting function between IPv4 and IPv6, manages the network on the routers side by IPv6 while it manages the network on the LAN server’s side by IPv4. A waste receptacle, with a trapdoor to suppress odors, operates independently of the raking device. Access to the infrastructure is controlled independently of the infrastructure operating system.