Shielding performance and protection from radiated RF energy at a cable’s point of entry to an enclosure are improved when a shield of the cable is AC coupled around an entire opening of the enclosure using a discoidal capacitor. The content server receives a WAP request message for wireless Internet service from a WAP terminal connected to a mobile communications network; processes the request; and constructs and transmits to the WAP terminal a response based on the WAP. The fixing part fixes the lower case and the upper case while both the cases overlap each other. A third impurity region is provided outside a gate electrode. The selected digital code is generated by an individual circuit corresponding to a respective one of the multiple data transmission protocols.