CWNA Guide to Wireless LANs, Second Edition

1. CWNA Guide to Wireless LANs, Second Edition Chapter One It’s a Wireless World

2. Wireless Networks First Meeting Agenda • Syllabus and Intro. • How to access class resources in your computer • Let’s get acquainted (forming groups) • Name • Industry certification • Networking or IT courses • Interests • Why you are taking the class • Expectations of yourself • Expectations of the instructor and the class • WebCT Login

3. Objectives • Describe how wireless technology is used in daily activities • Tell how wireless local area networks are used in applications such as education, business, travel, construction, and other areas • Explain the advantages and disadvantages of wireless technology

4. Real Life Wireless • What did Texas Department of Transportation do?

5. A Day in the Life of a Wireless User: Home • Wireless data communication has been the driving force in the 21st century • Hotspots: Locations where wireless data services are available • World-Wide growth rate: 350% a year • By 2007 revenue from hotspots will exceed $9 billion. • Wireless local area network (WLAN): Essentially identical to standard local area network (LAN) • Compare Ethernet LAN devices to Wireless LAN devices • Except devices not connected by wires • Can increase productivity (By how much?) • How do you use wireless at home?

6. A Day in the Life of a Wireless User: Car • Bluetooth wireless standard: Enables short range wireless communication • Used in many small devices • How is Bluetooth used in a car? • Bluetooth on the Road.

7. A Day in the Life of a Wireless User: Office • Fixed broadband wireless: Wireless transmissions between immobile devices • Typically between office buildings • Utilizes small, customized antennas • Otherwise known as WiMax • Free space optics (FSO): Alternative to high-speed fiber optic transmissions

8. A Day in the Life of a Wireless User: Field • Handheld devices used to connect to nearest cell tower • Cell tower connects to local telephone company • Telephone company connects to appropriate resources • Such as e-mail servers

9. A Day in the Life of a Wireless User: On Site • Radio frequency identification (RFID) tags: • “Electronic barcodes” • Used to identify items • Can be read if anywhere within range of transmitted radio signal • Depending on device

10. A Look at Wireless Technologies • Wireless technology woven throughout many aspects of life • Useful to get overview of some current technologies in today’s wireless world

11. Wireless Local Area Networks (WLANs) • Wi-Fi (Wireless Fidelity): Based on standard that transmits at up to 11 Mbps • Computers on WLAN must have wireless network interface cards (wireless NIC or Wireless adapter) • Performs same basic functions as standard NIC, plus more • Access point (AP): Transfers signals between wireless NICs • Patch cable connects AP to wired LAN or Internet

12. Wireless Local Area Networks (continued) Wireless LAN

13. Wireless Local Area Networks (continued) Home wireless LAN

14. Bluetooth • Low-power wireless data and voice transmission technology • Bluetooth devices communicate via radio modules • Link manager: Software that helps identify other Bluetooth devices, creates links between devices, and sends and receives data • Transmit data at up to 1 Mbps over 10 meters • Bluetooth devices within range of each other automatically connect • Master and slave Piconet: Bluetooth network containing a master and at least one slave

15. Telecommunications Links • Integrated Services Digital Networks (ISDN): Transmits at 256 Kbps • T-1 lines: Transmit at 1.544 Mbps • Cable modems: Use television cable connection • Digital subscriber lines (DSL): Use telephone lines • WiMax: Signal transmitted between antennas • Up to 75 Mbps and over up to 35 miles • Fixed Broadband

16. Telecommunications Links (continued) • FSO: Transmit at speeds up to 1.25 Gbps over up to 4 miles • Line-of-site transmission Free space optics transceiver

17. Telecommunications Links (continued) Wireless office technologies

18. Cellular Telephony • Global Systems for Mobile (GSM) communications technology: Coverage includes most of US and parts of Europe and Japan • Transmission speeds up to 9.6 Kbps • Information transmitted based on Wireless Application Protocol (WAP) • Standard way to transmit, format, and display data for devices like cell phones and handheld devices

19. Cellular Telephony (continued) • WAP cell phone runs a microbrowser that uses Wireless Markup Language (WML) instead of HTML • WAP gateway or proxy: Translates between WML and HTML WAP communications

20. Radio Frequency Identification (RFID) • Like an electronic barcode: • Can contain larger amounts of updatable information • Information transmitted via radio waves • Range typically about 1 foot at 5 Mbps RFID tag http://news.bbc.co.uk/2/hi/science/nature/4545252.stm

21. Wireless Technology Categories Typical wireless technologies

22. Wireless LAN Applications: Education • Educational institutions some of first adopters of WLANs • Dramatic advantages in teaching and learning • Wireless LAN connections offer students important degree of freedom • WLAN technology translates into cost savings for colleges • Reduces need for wiring and infrastructure • Fewer computer labs necessary

23. Wireless LAN Applications: Education (continued) Campus access point locations

24. Wireless LAN Applications: Business • Wireless LAN technologies have significantly changed how business conducted • Meetings not confined to conference rooms • Easier to connect to network resources and Internet • Can create office in space where traditional infrastructure does not exist

25. Wireless LAN Applications: Travel • Travel industry perhaps adopted wireless technologies more than any other industry • Many airport terminals provide wireless hotspots • Several large airlines providing wireless capabilities to passengers during flights • Some airlines use WLAN technology to communicate with aircraft on ground • Some airlines use WLAN technology to facilitate maintenance tasks • Some airlines use new wireless data service to send and receive messages

26. Wireless LAN Applications: Construction • Wireless technology has greatly benefited construction industry • Better management of resources • Better management of paperwork • Construction equipment being fitted with wireless terminals • “Smart” equipment • GPS information can provide location information to within centimeters

27. Wireless LAN Applications: Warehouse Management • New products arrive continuously • Must be inventoried and stored • Products being shipped must first be located then transferred to correct location and truck • Mistakes in inventory or inability to locate items can be devastating • Mark inventory with RFID tags • Warehouse management system (WMS) software: Can manage all activities from receiving through shipping • Utilize wireless technology

28. Wireless LAN Applications: Public Safety • Public safety departments using WLANs and GSM to communicate information with public safety vehicles • City-owned buildings equipped with APs • Large volumes of data can be quickly downloaded to vehicles • e.g., building floor plans, photographs of criminal suspects, and maps

29. Wireless LAN Applications: Healthcare • Wireless LAN point-of-care computer systems allow medical staff to access and update patient records immediately • Document patient’s medication administration immediately • Extensive use of RFID tags • Identify healthcare professionals, patients, medications • System verifies that medication being administered to correct patient in correct dosage • Eliminates potential errors and documentation inefficiencies

30. Wireless LAN Applications: Healthcare (continued) • Documentation process takes place at bedside where care delivered • Improves accuracy • Hospital personnel have real-time access to latest medication and patient status information • Wireless technology also used in other medical areas: • e.g., video pills

31. Wireless LAN Applications: Healthcare (continued) Video pill

32. Wireless Advantages and Disadvantages: Advantages • Mobility: Primary advantage of wireless technology • Enables individuals to use devices no matter where users roam within range of network • Increasingly mobile workforce is characteristic of today’s business world • WLANs give mobile workers freedom while allowing them to access network resources • “Flatter” organizations: WLANs give team-based workers ability to access network resources needed while collaborating in team environment

33. Wireless Advantages and Disadvantages: Advantages (continued) • Easier and Less Expensive Installation: Installing network cabling in older buildings difficult and costly • Wireless LAN is ideal solution • Eliminating need for cabling results in cost savings • Significant time savings as well • Allows offices to reorganize easily • Increased Reliability: Wireless LAN technology eliminates certain types of cable failures and increases overall network reliability

34. Wireless Advantages and Disadvantages: Advantages (continued) • Disaster Recovery: Documented disaster recovery plan vital to every business • Hot site: Off-site facility that can run business’s operations if primary site is not available • Generally maintained by third party • Expensive • Cold site: Customer provides and installs equipment • Many businesses use cold sites and WLANs as major piece of disaster recovery plan • No consideration given to network cabling

35. Wireless Advantages and Disadvantages: Disadvantages • Security: Wireless signals broadcast in open air • Security for wireless LANs is prime concern • Unauthorized users might access network • War driving • Attackers might view transmitted data • Employees could install rogue access points • Attackers could easily crack existing wireless security • Older wireless products have very weak security features

36. Wireless Advantages and Disadvantages: Disadvantages (continued) • Radio Signal Interference: Signals from other devices can disrupt wireless transmissions • Or wireless device may be source of interference for other devices • e.g., Microwave ovens, elevator motors, photocopying machines, theft protection devices, cordless telephones • Solution: Locate source of interference and remove • Health Risks: Wireless devices emit RF energy • Not known if or to what extent low levels of RF might cause adverse health effects

37. Summary • Wireless devices and technologies enable users to roam almost anywhere and remain connected to data and voice networks • A WLAN, also known as Wi-Fi, functions the same as a standard wired network except devices send radio frequency signals through the air instead of being connected to the network by cabling • Bluetooth devices communicate using small radio transceivers called radio modules that are built into microprocessor chips

38. Summary (continued) • Two popular technologies are WiMax and free space optics (FSO) • Handheld devices can send and receive wireless signals using the Global System for Mobile (GSM) communications technology • RFID tags function as electronic barcodes • Wireless personal area networks (WPANs) cover technologies where the transmission generally extends only a few meters or feet, whereas wireless local area networks (WLANs) are generally restricted to 112 meters (375 feet)

39. Summary (continued) • Wireless LAN applications can be found in industries in which employees need the freedom to conduct business without being confined to a specific location • Wireless LANs have significant advantages, including increased mobility, easier and less expensive network installations, increased network reliability, and disaster recovery • Some of the disadvantages of wireless LANs include security, radio signal interference, and health concerns