Shielded networks cut down on electro-magnetic interference (EMI), which can result from cables being run close to high-voltage power lines, fluorescent lights, and other causes. In order for a network to be shielded, the cable, the jack, and the connector on the cable must all be shielded. Shielded Ethernet Keystone Jacks on ShowMeCables.com: goo.gl Products used in this video: Shielded Jack – 15-167 Punch-down tool – 3539.1 TL – goo.gl Standard Patch Panel – 15-175-012 – goo.gl Shielded Cat5e Cable – MPS24A4CM5E BK-FT – goo.gl Shielded Ethernet Cable – 510-01 BK – goo.gl