Public Wireless LAN Service.

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1 Public Wireless LAN Service

2 Radio Wave

3 Wave Frequency Amplitude Wave Length

4 Radio Wave Band Frequency Wavelength VLF 3-30 khz > 10 km LF khz 1-10 km MF 300-3,000 khz m HF 3-30 MHz m VHF MHz 1-10 m UHF 300-3,000 MHz cm SHF 3-30 GHz 1-10 cm EHF GHz 1-10 mm

5 ISM Band Industrial, Scientific, and Medical Define by ITU-R Anyone can use Subject to Local usage policy

6 Well Known ISM Band 2450 MHz band for Bluetooth 5800 MHz band for HIPERLAN 2450 MHz and 5800 MHz band for IEEE MHz band for Microwave Oven 915 MHz, 2450 MHz and 5800 MHz for Cordless Phone MHz for RFID devices

7 2.4 GHz Wifi Channels

8 Wireless Technologies Wireless LAN (IEEE ) Wireless PAN (IEEE ) Wireless Broadband (IEEE )

9 Wireless LAN Standards

10 Wireless LAN Standards

11 Wireless LAN Standards b

12 Wireless LAN Standards b a

13 Wireless LAN Standards b a g

14 Wireless LAN Standards b a g n

15 IEEE Bitrate 1 or 2 Mbps + FEC code Running on 2.4 GHz ISM Band Direct Sequence Spread Spectrum (DSSS)

16 IEEE b Running on 2.4 GHz ISM Band Usually running in 11 channel range Provide up to 11 Mbps raw data rate Backward Compatible with (DSSS) May caused interference with other devices

17 IEEE g Running on 2.4 GHz ISM Band Up to 54 Mbps raw data rate Typically 20 Mbps througthput Physical Signal Modulation OFDM with CCK Backward compatible with and b

18 IEEE a Running on 5 GHz ISM Band Less Crowded Effective range is less than 2.4 GHz Provide Bitrate up to 54 Mbps Not available in some country (e.g., Thailand) OFDM

19 IEEE n Available on 2.4 GHz and 5 GHz ISM Band Multiple-Input Multiple-Output (MIMO) Backward compatible with a (5 GHz) and b/g (2.4 GHz) OFDM

20 Wireless NIC

21 Wireless NIC

22 Wireless NIC

23 Wireless Access Point

24 Wireless LAN Network

25 2.4 GHz Wifi Channels

26 Wireless LAN Network

27 Wireless LAN Network 1

28 Wireless LAN Network 1 6

29 Wireless LAN Network

30 Wireless LAN Network

31 Wireless LAN Network

32 Roaming

33 Hidden Node Problem

34 Exposed Terminal Problem

35 IEEE Frame Types

36 IEEE Frame Types Management Frames

37 IEEE Frame Types Management Frames Association Request

38 IEEE Frame Types Management Frames Association Request Association Response

39 IEEE Frame Types Management Frames Probe Request Association Request Association Response

40 IEEE Frame Types Management Frames Probe Request Probe Response Association Request Association Response

41 IEEE Frame Types Management Frames Probe Request Probe Response Association Request Association Response Beacon

42 IEEE Frame Types Management Frames Probe Request Probe Response Beacon Authentication Association Request Association Response

43 IEEE Frame Types

44 IEEE Frame Types Control Frames

45 IEEE Frame Types Control Frames Request to send (RTS)

46 IEEE Frame Types Control Frames Request to send (RTS) Clear to send (CTS)

47 IEEE Frame Types Control Frames Request to send (RTS) Clear to send (CTS) Acknowledgement

48 IEEE Frame Types Control Frames Acknowledgement Data Frames Request to send (RTS) Clear to send (CTS)

49 Adaptive Rate Selection

50 Authentication and Association Types

51 Authentication and Association Types Unauthenticated and Unassociated

52 Authentication and Association Types Unauthenticated and Unassociated Authenticated and Unassociated

53 Authentication and Association Types Unauthenticated and Unassociated Authenticated and Unassociated Authenticated and Associated

54 Radio Wave

55 Radio Modulation

56 Omni Directional Antenna

57 Omni Directional Antenna

58 Omni Directional Antenna

59 Directional Antenna

60 Signal-to-Noise (SNR) ratio Signal (db) - Noise (db) >40dB SNR = Excellent db SNR = Very good db SNR = Log signal db SNR = Very low signal 5-10 db SNR = No signal, not association

61 Directional Antenna

62 CAntenna

63 Wireless Security

64 Wireless Security Open Authentication

65 Wireless Security Open Authentication Wired Equivalent Privacy (WEP)

66 Wireless Security Open Authentication Wired Equivalent Privacy (WEP) Wi-Fi Protected Access (WPA)

67 Lab

68 ~wiboon.w/content/view/58/40/

69 Wireless LAN Installation Site Survey Installation

70 Wireless LAN Site Survey Tools Airmagnet Ekahau site Survey Netstumbler

71 Site Survey Consideration Understand the wireless requirement Obtain a facility diagram Visual inspect the facility Identify coverage areas Verify access point locations Document findings Access existing network infrastructure Determine preliminary access point locations

Chapter 10: Wireless LAN & VLANs

Chapter 10: Wireless LAN & VLANs Abdullah Konak School of Information Sciences and Technology Penn State Berks Wireless Transmission for LAN Radio Frequency Transmission (RF) Infrared Transmission 2 1