IEEE 802.3ab 协议规范 1000B ASE-T Type 1000BASE-T PCS, type 1000BASE-T PMA sublayer, and type 1000BASE-T Medium Dependent Interface (MDI) are defined. This supplement provides fully functional, electrical and mechanical specifications for the type 1000BASE-T PCS, PMA, and MDI. This supplement also specifies the baseband medium used with 1000BASE-T.