XGMII

The media-independent interface (MII) was originally defined as a standard interface to connect a Fast Ethernet (i.e., 100 Mbit/s) medium access control (MAC) block to a PHY chip. The MII is standardized by IEEE 802.3u and connects different types of PHYs to MACs. Being media independent means that different types of PHY devices for connecting to different media (i.e. twisted pair, fiber optic, etc.) can be used without redesigning or replacing the MAC hardware. Thus any MAC may be used with any PHY, independent of the network signal transmission medium.

10 gigabit media-independent interface (XGMII) is a standard defined in IEEE 802.3 designed for connecting full duplex 10 Gigabit Ethernet (10GbE) ports to each other and to other electronic devices on a printed circuit board (PCB). It is now typically used for on-chip connections. PCB connections are now mostly accomplished with XAUI. XGMII features two 32-bit datapaths (Rx & Tx) and two four-bit control flows (Rxc and Txc), operating at 156.25 MHz DDR (312.5 MT/s).10