The RTL8306MB-CG is a 6-port 10/100M Ethernet switch controller that integrates memory, six MACs, and five physical layer transceivers for 10Base-T and 100Base-TX operation into a single chip. It supports a (T)MII/RMII interface for external devices to connect to the 6th MAC. The external device could be a routing engine, HomePNA, HomePlug, or VDSL transceiver depending on the application