The Ethernet MAC is defined in IEEE Std 802.3-2008 clauses 2, 3, and 4. A MAC is responsible for the Ethernet framing protocols described in Ethernet Data FormatEthernet Data Format and error detection of these frames. The MAC is independent of and can connect to any type of physical layer device.
The MAC CONTROL sublayer is defined in IEEE Std 802.3-2008 clause 31. This provides real-time flow control manipulation of the MAC sublayer.
Ethernet MAC provides MAC CONTROL and MAC sublayers, in all modes of operation.