Introduction to NetworkingChapter ObjectivesChapter Objectives (cont.)Slide 4Slide 5Networking OverviewTypes of Local Area NetworksSlide 8Slide 9Network TopologiesSlide 11Slide 12Slide 13Slide 14Slide 15Network CablingSlide 17Slide 18Slide 19Slide 20Access MethodsEthernet Issues and ConceptsOSI ModelSlide 24Slide 25Slide 26Slide 27Slide 28Networking ProtocolsNetwork AddressingSlide 31Slide 32Slide 33Slide 34Configuring NetworkingSlide 36Slide 37Network TroubleshootingSlide 39Slide 40Slide 41Dial-up NetworkingSlide 43Slide 44Internet SoftwareInternet SecurityNetwork TerminologyWireless Networks OverviewWireless Networks TypesSlide 50Slide 51Wireless Network Security OverviewAuthentication and WEPDefault SettingsIntroduction to NetworkingDefinitions and TermsChapter ObjectivesAfter completing this chapter you will:•Be able to differentiate between peer-to-peer and server-based networks.•Be able to identify a network topology.•Understand the different types of network cabling.•Be able to explain the differences between various network access methods.•Understand Ethernet issues.•Identify OSI model layers.•Be able to explain when a specific network protocol is used.•Understand the difference between a MAC address and an IP address.Chapter Objectives (cont.)After completing this chapter you will:•Be able to correctly apply IP addressing concepts.•Understand the purpose of DHCP, WINS, and DNS.•Be able to properly configure a NIC for network connectivity.•Be able to use common network troubleshooting tools.•Be able to access a network printer.•Understand dial-up networking concepts and define commonly used network terms.Chapter Objectives (cont.)After completing this chapter you will:•Be able to define and label the basic parts of a wireless network.•Know that wireless networks operate at layers 1 and 2 of the OSI model.•Understand the difference between the two main types of wireless networks: ad hoc and infrastructure.•Know the three types of wireless NICs.•Understand the difference between a BSS and an ESS.•Be able to explain the purpose of an SSID and channel ID.•Know the three non-overlapping channel IDs used by the 802.11b standard.Chapter Objectives (cont.)After completing this chapter you will:•Understand the purpose of a wireless repeater.•Be able to explain the basic differences between the antennas and explain the concept of attenuation.•Know the difference between dBd and dBi.•Know the purpose and importance of a site survey.•Understand the difference between 802.11a, 802.11b, and 802.11g.•Understand the basics of wireless network security.Networking Overview•A network is two or more devices capable of communicating and sharing resources between them.•Two types of networks are LAN and WAN:–LAN (Local Area Network) – A group of devices sharing resources in a single area such as a room or a building.–WAN (Wide Area Network) – Two or more LANs communicating, often across large distances. The most famous WAN is the Internet.Types of Local Area Networks•Two types of LANs are Server-Based and Peer-to-Peer Network:–Server-Based Network – A basic type of LAN wherein users login to a controlling computer, called a server and is more secure. The server contains information about who can connect to the network and to what shared resources. It also provides some of these resources. These networks normally consist of 10 or more computers.–Peer-to-Peer Network – One of two basic types of LANs wherein each computer user acts as a server. Each computer stores password and sharing information for its own resources. Usually has fewer than 10 computers.•NOS (Network Operating System) – Special operating system on a server containing utilities for managing users, resources, and security.Types of Local Area NetworksServer-Based NetworkNetwork – Figure # 1Types of Local Area NetworksNetwork – Figure # 2Peer-to Peer NetworkNetwork Topologies•Network Topology – Maps of how the physical or logical paths of network devices connect. The three major topologies are star, ring, and bus.•Star Topology – Most common Ethernet network topology where each device connects to a central hub or switch.•Hub – A device used with the Universal Serial Bus or in a star network topology that allows multiple device connections.•Switch – In star networks, a Layer 2 central controlling device. A switch looks at each data frame as it comes through each port.•Ring Topology – Network that is physically wired like a star network but, logically in a ring; passes control from one device to the next in a continuous fashion using a special data packet called a token. Used in Token Ring networks.•Bus Topology – Network wherein all devices connect to a single cable. If the cable fails, the network is down.•Mesh Topology – Network where all devices connect to each other by cabling to provide link redundancy for maximum fault tolerance. Most likely in WANs.Network TopologiesNetwork – Figure # 3Hub/SwitchNetwork TopologiesNetwork – Figure # 4Star TopologyNetwork TopologiesLogical Ring TopologyNetwork – Figure # 5Network TopologiesNetwork – Figure # 6Bus TopologyNetwork TopologiesNetwork – Table # 1 Network TopologiesNetwork CablingCable is normally used as a medium for transporting network data. The most common types are twisted-pair and fiber-optic, although coax is still used in some old networks.•Twisted-Pair Cable – Network cable of eight copper wires twisted into four pairs to prevent crosstalk.–UTP (Unshielded Twisted-Pair) – Most common network cable that comes in different categories for different uses. Categories 3 (voice-grade), 4, and 5 (data). It is unshielded and more susceptible to interference.–STP (Shielded Twisted-Pair) – Same as UTP cable, but with extra foil to prevent outside noise from interfering with data on the cable.•Crosstalk – Where signals from one wire interfere with the signal on an adjacent wire.•Plenum cable is treated with Teflon or fire retardant materials to reduce the risk of fire. It produces less smoke and is less toxic when burning.Network Cabling•Fiber-Optic Cable – An expensive network cabling made of plastic or glass fibers that carry data in the form of light pulses. Most often used to connect network devices such as switches together into a network backbone or for connecting networks together in a WAN. More secure and not affected by crosstalk