cted to nodes. . Carry the highest amount of LAN traffic. Layer 2 switches Are connected to nodes (devices) on floors. Carry less traffic than Layer 3 switches. Copper, Wi-Fi, and fiber media tie nodes and switches together into a network. Layer 3 Switches-Transmitting Data between Switches and Data Centers Layer 3 switches are large-capacity switches that transmit data between Layer 2 switches and centralized applications in data centers. Layer 3 switches are also referred to as core or backbone switches. They tie together buildings located in, for example, hospitals, universities, and enterprise campuses. Core switches are not connected directly to end-users' devices. A backbone switch has connections to multiple switches and to routers, but not to LAN nodes listed in Table 2-1. On large LANs, if a link to a core switch is down, the backbone switch can often route traffic around the disabled switch to a functioning switch. IP Addresses in Layer 3 Switches Layer 3 switches are called Layer 3 because they route messages to devices via their IP address. Layer 3 devices are considered Network Link nodes equipment. Layer 3 Network Link switches send messages only to other www.TechnicalPDF.com switches and routers, not to nodes such as printers and individuals' devices. All networks including broadband, cellular and the Internet, have Layer 3 switches for transmitting data and voice within backbone networks. See Chapter 1, "Computing and Enabling Technologies," for backbone networks. Layer 2 Switches-Links to Nodes In LANs, Layer 2 switches are located in wiring closets on individual floors. The switches typically have between 8 and 24 ports with a dedicated port for each device connected to them. Each port is connected to users' computers, Wi-Fi access points, printers, and other LAN nodes. Because each device is cabled to its own dedicated port, messages they transmit are not broadcast to all users. For example, a manager is able to send the same e- mail or video to staff on various floors. These messages are sent 