phylib has provided the API Ethernet MAC drivers have used to control Copper PHYs for many years. However with the advent of MACs/PHYs with bandwidth of over 1Gbps, SERDES interfaces and fibre optical modules, phylib is not sufficient. phylink provides an API which MAC drivers can use to control these more complex and dynamic, possibly hot-pluggable PHYs. This presentation will explain why phylink is needed, how it differs from phylib, and describe how to convert a MAC driver from phylib to phylink in order to make use of its new features. The kernel support for SFP modules will also be detailed, including how the MAC needs to handle hot-plugging of the PHY, which can be copper or fibre.