introduction€¦ · nes440 wireless networks 16 history of the wireless technologies (3) 1970:...
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NES440 Wireless Networks 1
Introduction
NES440 Wireless Networks
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Wireless Networks 3NES440
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Outline What is “Wireless and Mobile Networking”?
What is wireless networking?
What is Mobility?
Degrees of Mobility
History of Wireless
Types of Wireless Networks Categories of Wireless Networks
Comparison among the types of wireless networks
Wireless Spectrum
Why go wireless? Ubiquitous computing
Benefits of Wireless Networking
Applications of Wireless networks
Statistics and Trends of Wireless Networks
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NES440 Wireless Networks 6
What is “Wireless and Mobile Networking”?
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What is Wireless Networking?
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What is Wireless Networking?
Enabling people to communicate and access applications and information without wires Information is transmitted using electromagnetic (EM) waves
Providing people with the freedom of movement and ability to easily and dynamically extend applications to different parts of a building, city, or anywhere in the world
Also called tether-less (or tether-free) communication
Characteristics on an EM wave: Travels in the air at the speed of light (c = 3x108 m/s)
Has a frequency (f) and wavelength (l)
l is the distance occupied by a single cycle of the signal
l = c / f
Example: for the 2.4GHz Wi-Fi signals, l = 12.5 cm
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What is Mobility?
Initially, the Internet and Telephone Networks were designed assuming that the user terminals are stationary. That is: No change of location during a call or connection
User terminals access the network always from fixed locations
Mobility vs. portability Mobility means changing the point of attachment to the network
online (a user property)
The user can communicate with anyone, from anywhere, at anytime
Portability means changing the point of attachment to the network offline (a device property)
The device can be connected to the network from anywhere at anytime
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Degrees of Mobility
Walking Users
o Low speed
o Small roaming area
o Usually uses high-bandwidth/low-latency access
Vehicles
o High speeds
o Large roaming area
o Usually uses low-bandwidth/high-latency access
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NES440 Wireless Networks 11
History or Wireless
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Early forms of wireless communications
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Early forms of wireless communications
Wireless communication and networking have been around for many years
Native Americans waving buffalo skins over a fire to send smoke signals over big distances
The use of pulsing lights carrying information through Morse code between ships
E.g.; SOS (Save-Our-Ship or Save-Our-Souls)
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History of the Wireless Technologies (1) 1831: Faraday demonstrates electromagnetic induction 1864: Maxwell develops the theory of EM field 1880: Hertz discovered the electromagnetic waves 1896: Guglielmo Marconi
First demonstration of wireless telegraphy Built on work of Maxwell and Hertz to send and receive Morse
Code (first radio broadcasts were digital!) Based on long wave (>> 1 km), spark transmitter technology,
requiring very large, high power transmitters First used by British Army and Navy in the Boer War (first
research funding by the military!)
1907: Commercial Trans-Atlantic Wireless Service Huge ground stations: 30×100m antenna masts Beginning of the end for cable-based telegraphy
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History of the Wireless Technologies (2) WW I: Rapid development of communications
intelligence, intercept technology, cryptography 1920: Marconi discovers shortwave (<100 m) radio
Longwave follow contour of earth Very high transmit power, 200 KW+
Shortwaves reflect, refract, and absorb, like light Bounce off ionosphere Higher frequencies made possible by vacuum tube (1906) Cheaper, smaller, better quality transmitters
1920: First commercial radio broadcast (Pittsburgh) 1921: First Mobile Radio
Wireless dispatch system for Detroit Police
1946: First Mobile Telephone Service by AT&T Half-duplex (Push to talk)
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History of the Wireless Technologies (3) 1970: First Cellular Phone Service by AT&T
Cell, handoff, and roaming
1971: First Wireless Data Network Aloha at University of Hawaii
1974: FCC allocates 40 MHz for cellular telephony
1982: European GSM and Inmarsat established
1984: Breakup of AT&T
1984: Initial deployment of AMPS cellular system
1990: First Commercial Wireless LAN Product AT&T WaveLAN
1997: First Wireless LAN Standard IEEE 802.11, 2Mbps
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NES440 Wireless Networks 17
Types of Wireless Networks
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Categories of Wireless Networks
Wireless networks are categorized depending on the size of the physical area that they cover.
The following categories of wireless networks satisfy diverse user requirements:
Wireless Personal-Area Network (WPAN) E.g.; Bluetooth and Zigbee
Wireless Local-Area Network (WLAN) E.g.; Wi-Fi
Wireless Metropolitan-Area Network (WMAN) E.g.; WiMax
Wireless Wide-Area Network (WWAN) E.g.; GPRS
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Wireless Networks 19NES440
Another Classification of Wireless Networks
Wireless networks can also be classified as:
Infrastructure-based Wireless Networks
Cellular Networks
Wireless LANs
Infrastructure-less Wireless Networks
Wireless PANs
Mobile Ad hoc Networks (MANETs)
Wireless Sensor Networks (WSNs)
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Comparison of Wireless Network Types
Type Coverage Performance Standards Applications
WPAN Within reach of a person
Moderate Bluetooth, UWB
IEEE 802.15, and IrDa
Cable replacement for peripherals
WLAN Within a building or campus
High IEEE 802.11,
Wi-Fi,
and HiperLAN
Mobile extension of wired networks
WMAN Within a city High Proprietary,
IEEE 802.16, and WiMAX
Fixed wireless of homes and businesses to the Internet
WWAN Worldwide Low CDPD and Cellular 2G, 2.5G, and 3G
Mobile access to the Internet from outdoor areas
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Comparison of Wireless Technologies (1)
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Comparison of Wireless Technologies (2)
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Wireless Spectrum (1)
30 MHz 30 GHz3 GHz300 MHz
Broadcast TV• VHF: 54 to 88 MHz, 174 to 216 MHz• UHF: 470 to 806 MHz
FM Radio• 88 to 108 MHz
Digital TV• 54 to 88 MHz, 174 to 216 MHz, 470 to 806 MHz
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Wireless Spectrum (2)
30 MHz 30 GHz3 GHz300 MHz
Wireless WAN3G Broadband Wireless• 746-794 MHz, 1.7-1.85 GHz, 2.5-2.7 GHz
Wireless WANCellular Phone• 800-900 MHz Wireless WAN
Personal Communication Service (PCS)• 1.85-1.99 GHz
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Wireless Spectrum (3)
30 MHz 10 GHz3 GHz300 MHz
Wireless LAN (IEEE 802.11b/g)• 2.4 GHz
Wireless MAN(WiMAX) • 10-16 GHz
Wireless PAN(Bluetooth)• 2.4 GHz
Wireless LAN (IEEE 802.11a)• 5 GHz
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Why Go Wireless?
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The Need for Wireless and Mobile Networking
Demand for Ubiquitous (or Pervasive) Computing
Anywhere, anytime computing and communication You don’t have to go to the computer lab to check your email
Pushing the computers more into the background Focus on the task and life not on the computer
Use computers seamlessly to help you and to make your life much easier
Computers should be location-aware Adapt to the current location
Discover location-dependent services
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Sample Applications of Ubiquitous Computing
You walk into your office and your computer automatically authenticates you through your active badge and logs you into the system
You go to a foreign building and your PDA automatically discovers the closest public printer where you can print your documents
The technician gets close to a malfunctioning machine in the factory and his tablet PC brings up the diagnostics screen and downloads the engineering drawing and specs of the machines
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Benefits of Wireless Networking
Increasing Efficiency and Accuracy Individuals can communicate no matter where they are, within
range of communication
Team-based workers can access network resources while collaborating in a team environment
Easier and less expensive installation: Installing network cabling in older buildings is difficult and costly Wireless networking is an ideal solution
Eliminating cabling saves money and time
Allows offices to reorganize easily
Increased reliability: Eliminates certain types of cable failures
Increases overall network reliability
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Application: Efficient Workflow
Access to multiple sources Minimize travel No 2nd party involvement
Paperless information entry Status update Auditing Alerts
Security Server
MachineController
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Application: Retrofits
Wires can be less expensive if they are all run at one time when the facility is built
New applications such as maintenance sensing
Experimental deployment for process optimization
Commissioning new equipment Pressure?Vibration?
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Application: Cable Replacement
Moving machinery Festoon cables
Reaching great distances SCADA: Supervisory
Control And Data Acquisition
Crossing electrical and physical barriers
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Statistics and Trends of Wireless Networks
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Worldwide Mobile Subscriber Penetration
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Worldwide Wireless Telecom Spending Forecast
Spending ($B)
Growth
Source: IDC's Worldwide Black Book Query Tool, Version 03, 2010 (IDC #225505, October 2010)
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Estimated Wireless Subscriber Connections
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Wireless Service Revenue
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Minutes-of-Use and Messages
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Wireless Data Traffic
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Cell Sites Deployed
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Capital Investment
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Home Networking Equipment Trends
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Home Networking Equipment Trends
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Trends and Statistics of Wireless Mobile Services and Equipment (Self-Read)
http://mobithinking.com/mobile-marketing-tools/latest-mobile-stats
http://www.smartinsights.com/mobile-marketing/mobile-marketing-analytics/mobile-usage-statistics-2010-2015/
http://blog.nielsen.com/nielsenwire/press/nielsen-fact-sheet-2010.pdf
NES440 Wireless Networks 44
http://mobithinking.com/mobile-marketing-tools/latest-mobile-stats/a#subscribers
http://www.ctia.org/