|  |  | Overview
The previous chapter discussed LAN media and the IEEE model and how the data link layer provides reliable transit of data across a physical link by using the Media Access Control (MAC) addresses. This chapter introduces layer 2 LAN technologies. Ethernet, Fiber Distributed Data Interface (FDDI), and Token Ring are widely used LAN technologies that account for virtually all deployed LANs. In this chapter, you will learn about Ethernet, FDDI, and Token Ring, along with the IEEE specifications for each of these technologies. You will also learn about the LAN standards that specify cabling and signaling at the physical and data link layers of the OSI reference model. Y ou will also be introduced to layer 2 devices and basic Ethernet 10Base-T troubleshooting.