10 Best Cars for the Great American Road Trip. PORTLAND, Ore. (TheStreet) -- The Great American Road Trip isn't dead, it just needs some tweaking. Getting out the map, seeing the country and sleeping where the day takes you is a grand tradition that the automobile is becoming less and less vital to.
Another benefit from the use of toroids is that shield cans aren't necessary in order to isolate the toroidal coil from adjacent components. Toroids have an inherent self-shielding property. Specifically, the field from a toroidal inductor is pretty much self-contained.
Such NIDs are colloquially called smartjacks or  Intelligent Network Interface Devices  (INIDs) as an indication of their built-in intelligence, as opposed to a simple NID, which is just a wiring device. Smartjacks are typically used for more complicated types of telecommunications service, such as T1 lines.