1. A+ Guide to Hardware, 4e
Chapter 10
PCs on a Network

2. Objectives
• Learn about different types of physical network
architectures
• Learn how networking works with Windows
• Learn how to install a network card and connect to a
network
• Learn how to set up and secure a wireless network
• Learn about troubleshooting tools and tips for
network connections
A+ Guide to Hardware, 4e 2

3. Introduction
• Topics covered in this chapter:
– Technologies used to build networks
– How Windows supports a network connection
– How to connect a computer to a network
– How switches and routers interface networks
– How to setup and secure a wireless network
– How to troubleshoot a network connection
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4. Physical Network Architectures
• Elements providing an overview of networks
– The different sizes of networks
– The different technologies used by networks
– Some networking terms
• Network types commonly encountered
– Ethernet
– Wireless networks
– Telephone networks
– Mostly outdated token ring and FDDI networks
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5. Sizes of Networks
• A network links two or more computers
• PAN (personal area network)
– Consists of personal devices at close range
• LAN (local area network)
– Covers a small local area such as a home, or office
• MAN (metropolitan area network)
– Covers a large campus or city
• WAN (wide area network)
– Covers a large geographical area; e.g., the Internet
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6. Networking Technologies
• Factors driving network evolution:
– The type of data the network is intended to support
– The data capacity on the network
– How a network is to fit among other networks
• Bandwidth (data throughput or line speed):
– Analog systems: measured in cycles/sec (hertz or Hz)
– Digital systems: measured in bps, Kbps, or Mbps
• As networks grow, the need for bandwidth grows
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7. Additional Terms Used in Networking
• Node (host): one device on a network; e.g., server
• Network adapter: interfaces a PC with a network
– Network interface card (NIC): fits in a PCI slot
• Adapter (MAC, physical, or hardware) address:
– 48-bit (6-byte) id number hard-coded on card
– Example: 00-0C-6E-4E-AB-A5
• Network protocols: rules of communication
• Packets (datagrams or frames)
– Basic unit of data transmitted on a network
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8. Figure 10-1 Ethernet network card showing its MAC address
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9. Introducing Ethernet
• Ethernet types (categorized by speed):
– 10-Mbps Ethernet
– 100-Mbps or Fast Ethernet
– 1000-Mbps or Gigabit Ethernet
– 10-Gigabit Ethernet
• Types of cabling used:
– Two kinds of twisted-pair
• Unshielded twisted pair (UTP): four pairs of twisted wire
• Shielded twisted pair (STP): protected from EMI
– Coaxial cable: single copper wire with braided shield
– Fiber-optic: glass strands inside protective tubing
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10. Table 10-2 Variations of Ethernet and Ethernet cabling
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11. Figure 10-4 Fiber-optic cables contain a glass core for
transmitting light
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12. Introducing Ethernet (continued)
• Topology: arrangement of nodes in a network
• Bus topology: connects all nodes with a line (no hub)
• Star topology
– Connects nodes to central hub (or switch)
– The hub broadcasts a data packet to every device
– Switch uses a table to route packet to receiving device
• Scale networks by adding switches
• Star bus topology:
– Multiple switches form a bus network
– Nodes connected to each switch form a star
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13. Figure 10-6 Nodes on an Ethernet network can be connected to one
another in a star or bus formation
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14. Figure 10-10 A star bus network uses more than one switch
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15. Introducing Ethernet (continued)
• Attenuation: the weakening of a transmitted signal
• Repeater: device used to amplify a signal in a LAN
• Amplifier repeater: simply amplifies incoming signal
• Signal-regenerating repeater
– Reads and copies the signal (without noise)
– Transmits an exact duplicate of the original
• Ethernet uses a signal-regenerating repeater
– A switch or hub can act as the repeater
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16. Figure 10-14 A repeater on a network restores the clarity of the signal,
which degrades over a distance because of attenuation
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17. Wireless Networks
• Use radio waves or infrared light to connect PCs
• Popular in places where cables are difficult to install
• 802.11wireless (Wi-Fi or Wireless Fidelity)
– Types: 802.11g (most popular), 802.11b, 802.11a
– Two new standards: 802.11k and 802.11r
– Ad hoc mode: directly links two wireless devices
– Access point (AP): connects wireless device to LAN
• WiMAX (802.16 Wireless/802.16d and 802.16e)
– Used in public hot spots and as a last mile solution
• Bluetooth: short range standard; e.g., optical mouse
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18. Figure 10-16 Nodes on a wireless LAN connect to a cabled network by
way of an access point
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19. Telephone Networks
• Plain old telephone service (POTS)
– Switching creates closed circuits between phones
• VoIP (Voice over Internet Protocol)
– Uses packets of data to communicate
• Cellular WAN
– Made up cells created by base stations
• Cellular WAN standards
– GSM (Global System for Mobile Communications)
– CDMA (Code Division Multiple Access)
– TDMA (Time Division Multiple Access)
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20. Figure 10-20 A cellular WAN is made up of many cells
that provide coverage over a wide area
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21. Telephone Networks (continued)
• General Packet Radio Service (GPRS)
– New communication protocol using data packets
• Two types of transmission:
– Full-duplex: allows both users to talk and transmit
– Half-duplex: allows only one user on a channel
• Satellite phone: communicates with satellites
• Cordless phone: communicates with phone base
• Radio phone: uses VHF radio waves
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22. Token Ring and FDDI
• Token Ring is physically a star, logically a ring
• Components of a token ring:
– Controlled Access Unit (CAU)
– Multistation Access Unit (MSAU or MAU)
– Token Ring LAN card connecting node to MSAU
– UTP or STP cables with two twisted pairs
– RJ-45 or Universal Data Connector (UDC)
• Fiber Distributed Data Interface (FDDI)
– Uses a token that travels in a ring like a Token Ring
– Data frames travel on the ring without the token
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23. Figure 10-21 Full-duplex and half-duplex transmissions
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24. Windows on a Network
• Major software components on a network
• An operating system installed on each PC
– Network operating system (NOS) for larger networks
• Peer-to-peer network (workgroup)
– Each PC has the same authority on the network
• Client/server model (domain)
– Access to network resources controlled by an NOS
– Server is called a domain controller
• A few network operating systems
– Windows 2003 Server, Novell NetWare, Linux
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25. Four Suites of Protocols
• TCP/IP (Transmission Control Protocol/Internet
Protocol)
– Primary protocol used on the Internet
• IPX/SPX (Internetwork Packet Exchange/Sequenced
Packet Exchange)
– Designed for use with Novell NetWare
• NetBEUI (NetBIOS Extended User Interface)
– Supports NetBIOS (Network Basic Input/Output
System)
• AppleTalk
– Proprietary networking protocol suite for Macs
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26. Figure 10-25 An operating system can use more than one method to
address a computer on the network, but at the network level, a MAC address
is always used to address a device on the network
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27. Four Suites of Protocols (continued)
• Using a protocol on the network
– Install a NIC card in the computer
– Connect network cable to network device; e.g., a switch
– NIC card binds to higher level protocol; e.g., TCP/IP
• How to identify which protocols are used in Windows
– Look at the properties of a network connection
• More than one OS protocol can be used on a network
• New protocols may be installed
• Network printers can be accessed in various ways
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28. Figure 10-26 Three Windows XP network protocols are installed and two
protocols are bound to this network card
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29. Addressing on a Network
• Four methods used to identify devices and programs
– Using a MAC address
– Using an IP address
– Using character-based names (host, domain, NetBIOS)
– Using a Port address
• IP addresses
– Used in TCP/IP to identify any device on the network
– 4 bytes (octets) separated by dots; e.g., 190.180.40.120
– System allows for up to 4.3 billion IP addresses
– First part identifies network, last part identifies host
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30. Figure 10-27 Computers on the same LAN use MAC addresses to
communicate, but computers on different LANs use IP addresses to
communicate over the Internet
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31. Installing a NIC and Connecting to a
Network
• Components needed to connect a PC to a network
– NIC and network port or wireless NIC card in the PC
– Patch cable
– Device for the PC to connect to, such as a router
• NIC card selection criteria
– NIC should match type of bus on motherboard
– NIC should match speed and type of network
– Wireless NIC should match network technology
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32. Installing a NIC Using Windows
2000/XP
• Overview of installation steps
– Determine whether driver or NIC is installed first
– If NIC precedes driver, install NIC and turn on PC
– Follow instructions in Found New Hardware Wizard
– Verify driver installation using the Device Manager
– Update the driver if necessary
– Connect patch cable to NIC port and network switch
• Configuring Windows 2000/XP to use a network
– Name computer in System Properties dialog box
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33. Figure 10-32 Windows XP uses the Computer Name Changes dialog box to
assign a host name to a computer on a network
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34. Installing a NIC Using Windows
2000/XP (continued)
• Questions to ask before configuring TCP/IP
– Will the PC use dynamic or static IP addressing?
– What are the IP address, subnet mask, default gateway?
• A question to ask if static IP addressing is used
– Do you use DNS?
• If so, what are the IP addresses of your DNS servers?
– Is a proxy server used to connect to other networks?
• If so, what is the IP address of the proxy server?
• Gateway: device that connects two networks
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35. Installing a NIC Using Windows
2000/XP (continued)
• Internet Protocol (TCP/IP) Properties dialog box
– Used to configure TCP/IP under Windows XP
– Dialog opened from Properties of Local Area Connection
• NWLink or NetBEUI protocol
– Used for network communication (excluding the Internet)
– Can be used in combination with TCP/IP
– Installed from Properties of Local Area Connection
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36. Figure 10-34 To configure TCP/IP under Windows XP, use the
Internet Protocol (TCP/IP) Properties dialog box
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37. Installing a NIC Using Windows 9x/Me
• Overview of installation steps:
– Physically install the NIC and turn on the PC
– Follow instructions of the Wizard
– Verify the installation using Device Manager
• Assigning a computer name
– Access Identification tab in Network dialog box
– Enter names of computer and workgroup
– Verify assignment in Network Neighborhood window
• Installing and configuring TCP/IP using Windows 98
– Use functions in the Network window
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38. Figure 10-40 To configure TCP/IP in Windows 98, select the binding and click
Properties to view the TCP/IP Properties dialog box
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39. Installing a Wireless Adapter in a
Notebook
• Wireless adapter uses a USB port or PC Card slot
• Installation package includes a CD and accessories
• Overview of steps for installing a Linksys adapter
– Install the software from the setup CD
– Plug the wireless adapter into a USB port
– Launch Found New Hardware and follow instructions
• Managing the issue of an unsigned driver
– Find approved driver or continue installation
• Deciding which installation utility to use
– Choose manufacturer’s utility over Windows XP’s
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40. Figure 10-45 Plug the wireless USB adapter into the USB port
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41. Installing a Wireless Adapter in a
Notebook (continued)
• Information displayed about a current connection:
– MAC address of access point device used by adapter
– The current channel the connection is using
– Transfer rate, throughput, link quality, signal strength
• Configuration changes you can make:
– Mode or network type
– The SSID (service set identifier)
– Encryption settings
– Tx rate
– TCP/IP configuration
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42. Figure 10-49 Opening screen to configure a Linksys wireless adapter
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43. Installing a Wireless Adapter in a
Notebook (continued)
• Connecting to a public hot spot using Windows XP
– Open Wireless Network Connection dialog box
– Select unsecured network from list and click Connect
– Open a browser to test the connection
– View link in Wireless Network Connection Status box
• Two ways to troubleshoot a connection
– Add network SSID in Wireless network properties
– Provide MAC address to network administrator
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44. Figure 10-57 Enter the SSID of a hot spot to which you want to connect
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45. How to Set Up Your Own Wireless
Network
• Two principal steps:
– Buy a wireless access point
– Configure AP and wireless PC for communication
• Providing security is critical for a successful network
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46. Security on a Wireless LAN
• Methods for securing a wireless connection:
– Disable SSID broadcasting
– Filter MAC addresses
– Data encryption; e.g., WPA (WiFi Protected Access)
– Change firmware default settings
– Update firmware
– Use a firewall
– Virtual private network (VPN)
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47. Figure 10-60 With tunneling, packets can travel over a wireless LAN and
the Internet in a virtual private network (VPN), but WEP or WPA applies
only to the wireless connection
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48. Choosing a Wireless Access Point
• Selection criteria
– The ability to use multiple security measures
– Supports for the 802.11 b/g wireless standards
– Good hardware reviews from other users
• An access point can be a standalone device
• An access point can also serve multiple purposes
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49. Configure and Test Your Wireless
Network
• Installing the hardware
– Position device and plug it in
– Connect the device using a network or USB cable
• Access point configuration is saved on firmware
• Configuring the access point
– Change default password to the administrative utility
– Select basic wireless settings, such as the channel
– Set up data encryption
– Choose whether to filter MAC addresses
– Save the settings and test the connection
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50. Figure 10-65 This wireless access point supports several encryption methods
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51. Troubleshooting a Network
Connection
• Some symptoms indicating a faulty NIC:
– You cannot make a connection to the network.
– My Network Places does not show any other PCs
– An error message displays during driver installation
• Displaying TCP/IP connection information
– Use Ipconfig under Windows 2000/XP
– Use Winipcfg under Windows 9x/Me
• Ping (Packet Internet Groper) diagnostic tool
– Sends a signal to a remote computer
– If remote PC is online and senses signal, it responds
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52. Summary
• Network: system interconnecting two or more PCs
• Basic network types: PANs, LANs, MANs, and WANs
• Bandwidth: amount of data transmitted per unit time
• Ethernet topologies: bus, star, star bus
• Wireless standards: 802.11g/b/a/k/r, WiMAX,
Bluetooth
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53. Summary (continued)
• Telephone technologies: POTS, VoIP, Cellular WAN,
satellite phone, cordless phone, and radio phone
• OS level protocols: TCP/IP, IPX/SPX, Net BEUI,
AppleTalk
• IP address: 32-bit address identifying network node
• Local Area Connection dialog box: used to install
and modify communication protocols
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