Computer concepts chapter05

Chapter LANs and WLANs Computer Concepts 2012 Chapter Contents      Section A: Network Building Blocks Section B: Wired Networks Section C: Wireless Networks Section D: Using LANs Section E: Security Through Encryption Chapter 5: LANs and WLANs 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 computer’s MAC address  050500 Some network technologies use home telephone or electric cabling for computer networks Chapter 5: LANs and WLANs 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 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        SECTION Network Building Blocks A Network Classifications LAN Standards Network Devices Clients, Servers, and Peers Physical Topology Network Links Communications Protocols Chapter 5: LANs and WLANs 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 Network Classifications  Personal Area Network (PAN) – interconnection of personal digital devices or consumer electronics  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) – covers a large geographical area and typically consists of several smaller networks Chapter 5: LANs and WLANs 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 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 Chapter 5: LANs and WLANs 10 Sharing Files  A homegroup is a collection of trusted networked computers that automatically share files and folders Chapter 5: LANs and WLANs 46 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 Chapter 5: LANs and WLANs 47 Sharing Printers Chapter 5: LANs and WLANs 48 Troubleshooting  Network problems can stem from a variety of sources – Cables – Signal strength – Security – Interference – Network devices – Settings – Switches Chapter 5: LANs and WLANs 49 SECTION E Security Through Encryption  Wi-Fi Security  Encryption Chapter 5: LANs and WLANs 50 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 51 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 52 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  Activate encryption by using a wireless network key Chapter 5: LANs and WLANs 53 Wi-Fi Security Chapter 5: LANs and WLANs 54 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 55 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 attack Chapter 5: LANs and WLANs 56 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 57 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) Chapter 5: LANs and WLANs 58 What Do You Think?  053100 Have you ever accessed a free WLAN? – A Yes B No C Not sure  053200 Do you believe that rogue WLANs can survive alongside for-profit broadband ISPs? – A Yes B No C Not sure  053300 Are broadband providers justified in limiting the terms of their service agreements to “one subscription, one customer”? – A Yes B No C Not sure Chapter 5: LANs and WLANs 59 Chapter Complete Computer Concepts 2012 ... address assigned to your computer on the Internet is derived from your computer s MAC address  050500 Some network technologies use home telephone or electric cabling for computer networks Chapter... 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... personal digital devices or consumer electronics  Local Area Network (LAN) – usually connects computers in a single building  Metropolitan Area Network (MAN) – public high-speed network with