Cat.5 Cat.5e/ Cat.6 Cat.5 內有八條線,兩兩雙絞,故稱之雙絞線,但有效的線只有1, 2, 3 and 6。 Cat.5e/ use the batter quality of the wire than Cat.5., so the Cat.5e wire even could be used on the 1000Base-T. Cat.6 和Cat.5e差不多,但在八股線中多了塑膠絕綠的設計,用以抑制雜訊。 STP and UTP STP (Shielded Twisted Pair,遮蔽式雙絞線) UTP (Unshielded Twisted Pair,無遮蔽式雙絞線)