A method of communication between an Ethernet Media Access Controller (MAC) and a physical interface (PHY) is disclosed. The method includes establishing communication between the MAC and the PHY via a first serial link in accordance with a Serializer Deserializer (SERDES) protocol. In a data transfer mode, data is transferred along the first serial link. Idle frames are transferred within an idle time gap along the link in an idle mode. The PHY is managed by encoding Management Data Input/Output (MDIO) information in one or more MDIO frames, and transferring the one or more MDIO frames within the idle time gap along the first serial link.