What is Transceiver?
Transceiver is combination of Transmitter and Receiver electronic circuits it is a physical hardware device. For Ethernet device, the Media Access Control circuit provide AUI (Attachment Unit Interface) to interface to Transceiver. While Transceiver transfer the digital signals to physical media for coaxial cable, twisted-pair cable or fiber optics. For Fast Ethernet device, the MAC controller provide MII (Media Independent Interface) to interface to Transceiver. In modern high integration products, most of the switches and hubs already build in transceiver into circuit, didnt provide such interface for other media options.
