10 Wireless Topologies Ad hoc topology: Connects two or more wireless computers communicating with each other only Infrastructure network: Connects wireless computers communicating with a network access point that provides access to a standard cabled network
17 Fiber Optic Cable Types Singlemode: Used for wide area networks (WANs) and other long cable runs Multimode: Used for local area networks (LANs) and short cable runs
18 Network Interface Adapters Called network interface cards (NICs) when installed in expansion slots Provide the computer with an interface to the network Usually take the form of an expansion card Can be integrated into the motherboard
19 Network Interface Adapter Functions Data encapsulation Signal encoding and decoding Data transmission and reception Data buffering Data-link protocol implementation Serial/parallel conversion Media Access Control (MAC)
20 NIC Purchasing Checklist Does the NIC use the correct data-link layer protocol? Does the NIC use the correct bus type? Does the NIC have the correct cable connector?
21 Installing a NIC To install a NIC into a standard expansion slot on a desktop computer: 1. Power off the computer. 2. Open the computer case. 3. Locate a free slot. 4. Remove the slot cover. 5. Insert the card into the slot. 6. Secure the card in the slot. 7. Close the computer case. NIC Installation
22 Network Interface Adapter Requirements Network interface adapters use the following hardware resources: An interrupt request (IRQ) An input/output (I/O) port address A memory address A direct memory access (DMA) channel Most network interface adapters require only an IRQ and an I/0 port address.
23 Troubleshooting Network Interface Adapters Network interface adapters rarely malfunction. Test all other networking components first. Use the network interface adapter manufacturers diagnostics. Replace network interface adapters rather than trying to repair them.
24 Understanding Ethernet Hubs A hub connects all of the computers on a star or ring network. Ethernet hubs are available in various sizes. A hub creates a shared network medium on a LAN.
25 Connecting Ethernet Hubs Most hubs have an uplink port. Uplink ports provide a straight-through circuit. To connect two hubs, plug a cable into the uplink port on one hub and into a standard port on the other hub. Play Video
27 Chapter Summary The network topology is the pattern used to connect computers and other devices with the cable or other network medium. The three primary LAN topologies are bus, star, and ring. Unshielded twisted-pair (UTP) cable in the star topology is the most common network medium used today. A network interface adapter provides the interface that enables a computer to connect to a network. The network interface adapter and its driver implement the data-link layer protocol on the computer. Hubs are devices that connect computers on a star or ring network.