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,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,SECTION,A,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,SECTION,B,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,SECTION,C,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,SECTION,D,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,Chapter 5: LANs and WLANs,#,5,SECTION,E,Chapter 5,LANs and WLANs,Chapter 5: LANs and WLANs,2,Chapter Contents,Section A: Network Building Blocks,Section B: Wired Networks,Section C: Wireless Networks,Section D: Using LANs,Section E: Security Through Encryption,FastPoll True/False Questions,Answer A for True and B for False,050100,In a network, a server is a computer that provides services to other computers called peers.,050200,Star, ring, and mesh are examples of network topologies.,050300,When you send an e-mail message over a network, it is chopped up into packets.,050400,The IP address assigned to your computer on the Internet is derived from your computers MAC address.,050500,Some network technologies use home telephone or electric cabling for computer networks.,Chapter 5: LANs and WLANs,3,FastPoll True/False Questions,Answer A for True and B for False,050600,The most popular type of wired network is Ethernet.,050700,Network speeds are measured in megabytes and gigabytes.,050800,Many wireless networks use radio waves to transmit data.,050900,Bluetooth is a wireless technology used for WANs.,Chapter 5: LANs and WLANs,4,FastPoll True/False Questions,Answer A for True and B for False,051000,A wireless infrastructure network,uses a centralized broadcasting device, such as a wireless access point or router.,051100,Wireless networks are less secure than wired networks.,051200,WEP, WPA, and PSK are examples of Wi-Fi networks.,051300,Public key encryption uses a public key to encrypt messages, but a private key is required to decrypt messages.,Chapter 5: LANs and WLANs,5,Chapter 5: LANs and WLANs,6,Network Building Blocks,Network Classifications,LAN Standards,Network Devices,Clients, Servers, and Peers,Physical Topology,Network Links,Communications Protocols,Question,052100,Networks come in many sizes and use many different technologies, yet they all need to communicate with each other. What is the key to network intercommunication?,A. Packet switching,B. Network protocols,C. Network topology,D. Peer-to-peer technology,Chapter 5: LANs and WLANs,7,Chapter 5: LANs and WLANs,8,Network Classifications,Personal Area Network,(PAN) interconnection of personal digital devices,Local Area Network,(LAN) usually connects computers in a single building,Metropolitan Area Network,(MAN) public high-speed network with range of about 50 miles,Wide Area Network,(WAN) consists of several smaller networks,Chapter 5: LANs and WLANs,9,LAN Standards,LAN technologies are standardized by the Institute of Electrical and Electronics Engineers (IEEE),Project 802 Local Network Standards,IEEE 802.3,ARCnet,Token Ring,FDDI,Ethernet,Chapter 5: LANs and WLANs,10,Network Devices,Each connection point on a network is referred to as a,node,To connect to a LAN, a computer requires network circuitry, sometimes referred to as a,network interface card,(NIC),A,networked peripheral, or network-enabled peripheral, is any device that contains network circuitry to directly connect to a network,A,network device, or network appliance, is any electronic device that broadcasts network data, boosts signals, or routes data to its destination,Network Devices,Chapter 5: LANs and WLANs,11,Chapter 5: LANs and WLANs,12,Clients, Servers, and Peers,Network devices can function as,clients,or as,servers,Application server,File server,Print server,Networks that include one or more servers can operate in,client/server mode,Chapter 5: LANs and WLANs,13,Physical Topology,The arrangement of devices in a network is referred to as its physical topology,Star,Ring,Bus,Mesh,Tree,Two similar networks can be connected by a device called a,bridge,Gateway,is a generic term for any device or software code used to join two networks,Chapter 5: LANs and WLANs,14,Network Links,A communications channel, or link, is a,physical,path or,frequency,for signal transmissions,Bandwidth,is the transmission capacity of a communications channel,Broadband,Narrowband,Chapter 5: LANs and WLANs,15,Communications Protocols,Rules,for efficiently transmitting data from one network node to another:,Divide messages into packets,Affix addresses to packets,Initiate transmission,Regulate flow of data,Check for transmission errors,Acknowledge receipt of transmitted data,Chapter 5: LANs and WLANs,16,Communications Protocols,A,packet,is a “parcel” of data that is sent across a computer network,Circuit-switching technology vs. packet switching technology,Chapter 5: LANs and WLANs,17,Communications Protocols,Every packet that travels over a network includes the address of its destination device,A,MAC address,is a unique number assigned to a network interface card when it is manufactured,An,IP addre,ss is a series of numbers used to identify a network device,IP addresses can also be obtained through DHCP,Chapter 5: LANs and WLANs,18,Wired Networks,Wired Network Basics,HomePNA and Powerline Networks,Ethernet,Ethernet Equipment,Ethernet Setup,Question,052200,Suppose youre setting up a network in your home or apartment. You want all of the computers to access the cable modem that provides Internet access. What is the one additional component that you should purchase to tie the network together?,A. A router,B. A network interface card,C. A file server,D. A HomePlug Ethernet port,Chapter 5: LANs and WLANs,19,Chapter 5: LANs and WLANs,20,Wired Network Basics,A,wired network,uses cables to connect network devices,Wired networks are fast, secure, and simple to configure,Devices tethered to cables have limited mobility,Chapter 5: LANs and WLANs,21,HomePNA and Powerline Networks,HomePNA (Home Phoneline Networking Alliance) networks utilize existing telephone wiring or coaxial cables to connect network devices,Special NICs and cables are required,A powerline network uses premises electrical wiring to form the infrastructure for a LAN,Chapter 5: LANs and WLANs,22,Ethernet,Simultaneously,broadcasts data packets to all network devices,IEEE 802.3,CSMA/CD protocol (,Carrier Sense Multiple Access with Collision Detection,),Vary in speed from 10Mbps to 100Gbps,Chapter 5: LANs and WLANs,23,Ethernet,On an Ethernet, data travels on a first-come, first-served basis. If two workstations attempt to send data at the same time, a,collision,occurs.,That data must be resent.,Ethernet Equipment,Chapter 5: LANs and WLANs,24,Chapter 5: LANs and WLANs,25,Ethernet Equipment,Ethernet adapter (designed to support the Ethernet protocols),Network hub,Network switch,Network router,RJ45 connector,Chapter 5: LANs and WLANs,26,Ethernet Setup,Ethernet Setup,Chapter 5: LANs and WLANs,27,Ethernet Setup,Chapter 5: LANs and WLANs,28,Most,routers,are configured using a browser. You should,change the network administrator password, then verify that DHCP is enabled,Chapter 5: LANs and WLANs,29,Wireless Networks,Wireless Basics,Bluetooth,Wi-Fi,Wi-Fi Equipment,Wi-Fi Setup,Question,052300,When youre setting up a wireless network, you see an option asking if you want to broadcast the network SSID. You should:,A. Change the default SSID and broadcast it while you set up the network.,B. Turn SSID broadcasting off so that hackers dont know the networks encryption key.,C. Make sure SSID is broadcasting so that your network is protected by strong encryption.,D. Activate SSID broadcasting or else the network devices wont be able to send data to the router.,Chapter 5: LANs and WLANs,30,Chapter 5: LANs and WLANs,31,Wireless Basics,A wireless network transports data from one device to another without cables or wires,RF (Radio Frequency) signals,Transceiver,Microwaves,Infrared light,Slower than wired networks,Security concerns,Chapter 5: LANs and WLANs,32,Bluetooth,Bluetooth,is a short-range, wireless network technology designed to make its own connections between electronic devices, without wires, cables, or any direct action from a user,Chapter 5: LANs and WLANs,33,Wi-Fi,Wireless networking technologies that are,compatible,with Ethernet,MIMO technology uses two or more antennas to send multiple sets of signals,Chapter 5: LANs and WLANs,34,Wi-Fi Equipment,Chapter 5: LANs and WLANs,35,Wi-Fi Equipment,If your computer is not pre-equipped with wireless circuitry, you can purchase and install a Wi-Fi adapter,Chapter 5: LANs and WLANs,36,Wi-Fi Equipment,Wireless network,setups,Wireless ad-hoc network,Wireless infrastructure network,Wireless access point,Wireless router,Chapter 5: LANs and WLANs,37,Wi-Fi Setup,Set up the,router,Connect to the router with a computer,Configure the router,Access the router setup utility,Create a new router password,Chapter 5: LANs and WLANs,38,Wi-Fi Setup,Enter an SSID for the network,Activate WEP, WPA, or PSK and create an encryption key,Set up the wireless workstations,Connect,an Internet access device,Wi-Fi Setup,Chapter 5: LANs and WLANs,39,Chapter 5: LANs and WLANs,40,Using LANs,LAN Advantages and Challenges,Sharing Files,Sharing Printers,LAN Parties,Troubleshooting,Question,052400,There are many ways to share files among the computers on a network. Which one of the following is the LEAST secure way to share files?,A. Use a file server.,B. Activate file sharing for the root directory of all the computers in the network.,C. Designate specific folders on your computer as shared.,D. Put files you want to share in the Public folder.,Chapter 5: LANs and WLANs,41,Chapter 5: LANs and WLANs,42,LAN Advantages and Challenges,LANs enable people to work together,Sharing networked software can reduce costs,Sharing data on a LAN can increase productivity,Sharing networked hardware can reduce costs,Sharing networked hardware can provide access to a wide range of services and specialized peripheral devices,Chapter 5: LANs and WLANs,43,LAN Advantages and Challenges,Resources become unavailable when network malfunctions,Networks may be,vulnerable,to unauthorized access,More vulnerable than standalone computers,Wireless networks can be tapped from a “snooping” computer,Networked computers are susceptible to an increasing number of worms, Trojan horses, and blended threats,Chapter 5: LANs and WLANs,44,Sharing Files,If you use Windows, it,automatically,detects,available LANs any time you turn on a workstation,To,connect,to a shared resource, you might be asked for a user ID and password,Sharing Files,Chapter 5: LANs and WLANs,45,Driving Mapping,Sharing Files,Chapter 5: LANs and WLANs,46,Folder Sharing,Chapter 5: LANs and WLANs,47,Sharing Printers,Three setups allow for,printer sharing,:,Set up printer sharing using a workstation printer,Set up printer sharing using a print server,Install printer with built-in networking,Sharing Printers,Chapter 5: LANs and WLANs,48,You can designate the printer attached to your computer as,sharable over the network.,Chapter 5: LANs and WLANs,49,LAN Parties,A,LAN party,is a gathering of people who connect their own computers to a LAN, usually to play multiplayer computer games,No special hardware usually is required,Game must have multiplayer capability,Chapter 5: LANs and WLANs,50,Troubleshooting,Network problems can stem from a,variety of sources,Cables,Signal strength,Security,Interference,Network devices,Settings,Chapter 5: LANs and WLANs,51,Security Through Encryption,Wi-Fi Security,Encryption,Question,052500,As part of the process of setting up a wired network, what should you remember to do?,A. Assign an IP address to each network device.,B. Remove the Ethernet card from any computer that has one.,C. Enable wireless security.,D. Disable the SSID.,Chapter 5: LANs and WLANs,52,Chapter 5: LANs and WLANs,53,Wi-Fi Security,Wireless networks are much more,susceptible,to unauthorized access and use than wired networks,LAN jacking, or war driving, is the practice of intercepting wireless signals by cruising through an area,Chapter 5: LANs and WLANs,54,Wi-Fi Security,Wireless encryption scrambles data transmitted between wireless devices and then unscrambles the data only on devices that have a valid encryption key,WEP (Wired Equivalent Privacy),WPA (Wi-Fi Protected Access),WPA2,PSK (Pre-shared Key),Activate encryption,by using a wireless network key,Wi-Fi Security,Chapter 5: LANs and WLANs,55,Chapter 5: LANs and WLANs,56,Encryption,Encryption,transforms a message so that its contents are hidden from unauthorized readers,Plaintext,has not yet been encrypted,An encrypted message is referred to as,ciphertext,Decryption,is the opposite of encryption,Cryptographic algorithm,Cryptographic key,Chapter 5: LANs and WLANs,57,Encryption,Weak,vs.,strong,encryption,AES (Advanced Encryption Standard),Encryption methods can be broken by the use of expensive, specialized, code-breaking computers,Brute-force method,Chapter 5: LANs and WLANs,58,Encryption,Public key encryption,(PKE) eliminates key-distribution problem, by using one key to encrypt a message and another key to decrypt the message,Chapter 5: LANs and WLANs,59,Encryption,When personal computer users want to encrypt e-mail or other documents, they turn to public key encryption software called PGP (Pretty Good Privacy) software,What Do You Think?,053100,Have you ever accessed a free WLAN?,A. YesB. NoC. Not sure,053200,Do you believe that rogue WLANs can survive alongside for-profit broadband ISPs?,A. YesB. NoC. Not sure,053300,Are broadband providers justified in limiting the terms of their service agreements to “one subscription, one customer”?,A. YesB. NoC. Not sure,Chapter 5: LANs and WLANs,60,Chapter 5 Complete,LANs and WLANs,
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