Classes Link / channel Cable / connectors Ethernet Speed Shielded / unshielded connector type Distance Class A 100 kHz Category 1 Class B 1 MHz Category 2 Class C 16 MHz Category 3 telephony & 10 mbps UTP RJ11/12/45 N.A. 25 MHz Category 5 10/100 mbps UTP/FTP RJ45 (2 pairs) 100m (90+10) Class D […]