The KSZ9131 is a completely integrated triple-speed (10Base-T/100Base-TX/1000Base-T) Ethernet physical-layer transceiver for transmission and reception of data on standard CAT-5, CAT-5e and CAT6 unshielded twisted pair (UTP) cable.The KSZ9131RNX provides Reduced Gigabit Media Independent Interface RGMII and the KSZ9131MNX offers the industry-standard GMII/MII (Gigabit Media Independent Interface/Media Independent Interface) for connection to GMII/MII MACs?in Gigabit Ethernet processors and switches for data