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Chapter 5

Chapter 5. Wireless Technologies. Objectives. In this chapter, you will learn to: Describe the status of wireless e-business today Discuss the origins of wireless communications and the commercialization of the radio range of the electromagnetic spectrum

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Chapter 5

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  1. Chapter 5 Wireless Technologies E-Business Technologies

  2. Objectives In this chapter, you will learn to: • Describe the status of wireless e-business today • Discuss the origins of wireless communications and the commercialization of the radio range of the electromagnetic spectrum • Describe two major short-range wireless technologies • Describe a wireless LAN and identify the IEEE 802.11 family of wireless LAN standards E-Business Technologies

  3. Objectives In this chapter, you will learn to: • Describe pager, cellular, satellite, and other wireless networks • Describe the devices, protocols, and languages of the wireless Web • Identify expectations for future wireless e-business E-Business Technologies

  4. Valued Gateway Client: Wireless E-Business • Wireless technologies include: • Wireless LANs where laptop computers transmit documents to printers three feet away • Information transmitted between two PDAs • Location positioning from an automobile • Medical images transmitted anywhere via satellite networks • As a practical matter, any WAN uses wireless communications since they are ubiquitous to long distance communications E-Business Technologies

  5. E-Business Technologies

  6. Wireless E-Business • Analysts predict a huge explosion in the demand for wireless devices, wireless e-business services, and the number of wireless Web users within the next three to five years • Future growth of wireless e-business based on wireless technologies advantages including: • Immediacy - e-business must occur with immediacy • Personalization - rational or not, users believe wireless technologies are personal as opposed to public • Localization - just like a wired connection, a physical location can be determined for each wireless connection E-Business Technologies

  7. A Brief History of Wireless Communication • In 1865, James Clerk Maxwell published his theory of electromagnetic radiation • In 1873, Heinrich Hertz corroborated Maxwell’s theory when he proved that electricity could be transmitted via electromagnetic waves • In 1895, a young inventor named Guglielmo Marconi began experimenting with radio waves to send messages • On December 12, 1901, first wireless transatlantic radio transmission sent from Cornwall, England to Signal Hill, St. John’s, Newfoundland E-Business Technologies

  8. Electromagnetic Spectrum • Radio: lowest frequency; the longest wavelength • Microwave: next shortest wavelength • Infrared: slightly longer wavelength than visible • Visible light: range of colors correspond to frequencies • Ultraviolet: just beyond the violet end of visible spectrum • X-rays: very short wavelength and high-energy • Gamma rays: shortest wavelength, highest frequency radiation E-Business Technologies

  9. E-Business Technologies

  10. Commercialization of the Radio Spectrum • 1920: KDKA, Pittsburgh, PA, the first commercial radio station in the U.S. • Circa 1920: Vladimir Zworykin developed technology to capture, transmit, and view images via wire • 1927: Philo Farnsworth was first to actually transmit images via radio waves • Federal Communications Commission (FCC) regulates the radio spectrum in U.S. • U.S. commercial radio spectrum is allocated in two parts: the FM band from 88.1 to 107.9 MHz, and the AM band from 540 to 1700 kHz E-Business Technologies

  11. Short-Range Wireless Technologies • Wireless technologies that work within the range of convenience: • about 10 feet (how does this help security?) • Technologies support such devices as: • Remote controls • PDA to PDA signaling • Wireless communication between laptops and printers • Two wireless technologies satisfy these needs: IrDA and Bluetooth E-Business Technologies

  12. IrDA • Infrared radiation (IR), part of the electromagnetic spectrum that lies just below the visible red range • The Infrared Data Association (IrDA) establishes standards for the IR hardware and software • IrDA communications require both devices have a transceiver (a combination transmitter and receiver) • IrDA requires a line-of-sight link E-Business Technologies

  13. Bluetooth • Radiofrequency (RF) technology operating at 2.45 GHz • Originally created to allow mobile phones to communicate with accessories • Requires small, low-power transceivers that can be added to a wireless device for Bluetooth transmissions • Operates on an unregulated section of the radio spectrum E-Business Technologies

  14. Wireless LANs • Usually include: • a wired LAN with computers, printers, servers, and other devices • portable devices such as laptops that can connect when necessary • access points (also called base stations) that allow devices to use RF transmissions -- access points are generally connected to a wire E-Business Technologies

  15. E-Business Technologies

  16. IEEE 802.11 Standards • Define the operation of wireless networks • Original standard specified transmission rate of one to two Mbps at 2.4 GHz range • 802.11b specifies up to 11 Mbps • 802.11a specifies up to 54 Mbps at 5.4 GHz • 802.11g specifies up to 54 Mbps at 2.4 GHz know how 802.11a differs from 802.11c - see Table 5-1 E-Business Technologies

  17. Long Distance Wireless Networks • Networks that provide wireless communications over longer distances than a wireless LAN include: • Pager • Cellular phone • Mobile data • Fixed wireless and fixed wireless broadband • Free space optics • Satellite networks E-Business Technologies

  18. Pager and Pager Networks • Pager networks include: paging terminals, transmitters, and pagers • Paging terminals accept messages and route messages to a transmitter for the local pager area or zone • The transmitter sends the message to the appropriate pager • Multiple local pager zones can be connected to form a wide area pager network E-Business Technologies

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  20. Cellular Phones and Cellular Networks • Metropolitan areas are divided into transmission areas called cells • Base stations service transmissions with cellular phones inside cell and with other cells • Base stations negotiate disconnect/connect of cellular phones as they move from cell to cell E-Business Technologies

  21. Advanced Mobile Phone Systems (AMPS) • Analog cell phone standard used in U.S., Japan, Scandinavia • Built on Frequency Division Multiple Access (FDMA) standard • Each call used two frequencies: one for transmitting and one for receiving • Assigned frequencies to one user at a time E-Business Technologies

  22. Time Division Multiple Access (TDMA) • Increases the capacity of a radio frequency (over AMPS) by dividing a frequency or channel into time slots • Allows up to six users to send timed, synchronized conversation fragments over a shared channel • Supports digital transmissions for voice, fax, data (at rates of 64 Kbps to 120 Mbps), multimedia and videoconferencing, and short text messaging via Short Message Service (SMS) E-Business Technologies

  23. Global System for Mobile (GSM) Communication • Hybrid technology, FDMA and TDMA based • Allows multiple users to share an RF channel (up to eight users) • Supports digital data transmissions • Supports text messaging with SMS • Operates at 900, 1800, and 1900 MHz E-Business Technologies

  24. Code Division Multiple Access (CDMA) • Based on direct sequence spread spectrum (DSSS) technology • Breaks up digitized and compressed voice data into many pieces, assigns code to each piece, then sends the pieces over many different frequencies — whichever frequencies happen to be available at transmission time • Upon arrival at the base station, voice data is then reassembled using these unique codes E-Business Technologies

  25. 3G Digital Cellular Networks • Enables users to receive high-speed voice, data, and multimedia transmissions via a cell phone E-Business Technologies

  26. Mobile Data Networks • MDNs provide data services to organizations with mobile employees • Subscribers can transmit data from their mobile devices to base stations positioned in specific areas • Base stations then forward the transmissions to a central messaging switch which is cabled to an organization’s LAN or mainframe E-Business Technologies

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  28. Fixed Wireless Broadband Systems • Provide wireless communications to or from a fixed location • Operate between 90 MHz to 40 GHz • Require line-of-sight positioning of antennae over relatively short ranges • Fixed Wireless Broadband (FWB) supports a data transmission rate of about 1 Mbps E-Business Technologies

  29. Free Space Optics • Uses laser to send light pulses through the air to a detector that can be up to three miles away • High transmission speeds (144 Mbps – 10 Gbps) over an unregulated portion of the radio spectrum • Can provide the “last mile of connectivity” between fiber-optic cable and nearby office buildings E-Business Technologies

  30. Communication Satellite Networks • Satellite networksconsist of: • strategically positioned Earthbound antennae • ground control facilities • thousands of weather, scientific, military, and navigational satellites orbiting the Earth • Communications satellites act as orbiting radio relay stations, containing thousands of transponders that receive voice, video, or data transmissions from Earth on one frequency and then relay them back to Earth on another frequency E-Business Technologies

  31. Geostationary Orbit (GEO)Satellite Network • Positioned 22,300 miles from Earth above the equator • Support two-way voice, video, and data communications • GEO satellites’ speed matches the Earth’s rotation, keeping a GEO satellite positioned directly above the same spot on Earth E-Business Technologies

  32. Low-Earth Orbit (LEO)Satellite Networks • Positioned from 400 – 1,600 miles above the Earth • Due to their proximity to the Earth, LEO satellites orbit the Earth in 1.5 – 2 hours to avoid the pull of gravity • A LEO satellite network is designed so that more than one satellite in the network is always visible • There are two kinds of LEO satellite networks: little LEO and big LEO E-Business Technologies

  33. Medium-Earth Orbit (MEO)Satellite Networks • Positioned from 1,500 – 6,500 miles above the Earth • Require fewer satellites per coverage area than LEO networks • Less transmission latency than GEO networks • Two MEO networks currently under development by: Teledesic LLC and ICO Global Communications, Inc. • Both networks are designed for high-speed IP data transmissions, voice, and broadband Internet access E-Business Technologies

  34. Global Positioning System (GPS) • Uses a network of 24 satellites to establish position of people, objects, etc. • Location-based services enable e-businesses to target offerings to customers based upon physical location • Use restricted by law to: • Locating people in emergencies • Providing telecommunications services • Requires customer consent to receive location-based service offerings E-Business Technologies

  35. The Wireless Web • Improvements in digital cellular technologies enabled processing of data, pictures, and voice on wireless handhelds • Long-term success of the wireless Web hinges on three major issues: • Improving view-ability of Web-based information on hand-held wireless devices • Mitigating slow transmission speeds • Ease of navigation E-Business Technologies

  36. Wireless Application Protocol (WAP) • Protocol suite or stack that makes it possible to access Internet resources from a hand-held wireless device • WAP was developed as a standard for the wireless Web by the WAP Forum, a consortium of wireless vendors • The WAP standard defines the wireless application environment and protocols which work across different platforms • WAP suite functions similarly to the protocols in the TCP/IP suite, but not compatible • Requires WAP gateway to communicate between wireless and TCP/IP networks IP E-Business Technologies

  37. WAP Protocol Suite E-Business Technologies

  38. Wireless Markup Language • Wireless applications are created with the Wireless Markup Language and the WMLScript • The Wireless Markup Language (WML), based on XML, is used to design content for small-screen devices • A WML document (page) is called a deck • Each deck contains one or more cards containing text, images, markup instructions, etc. • WMLScript, similar to JavaScript, manipulates the content on small screens and performs math functions E-Business Technologies

  39. WAP Gateway • A WAP-enabled client issues a request for a WML page • The request is sent to a WAP gateway • The WAP gateway formats the HTTP request, forwarding it to the Web server • The Web server sends a response to the WAP gateway • The WAP gateway formats the data, and sends it to the wireless device E-Business Technologies

  40. Accessing the Wireless Web • Palm VII PDA was first hand-held wireless device to make wireless data transmissions possible • PDA not equipped for phone calls, users needed separate cellular phone to get both wireless voice/data • Wireless industry developing hybrid wireless devices E-Business Technologies

  41. Effects of Wireless Technologieson E-Business • U.S. consumers see no compelling reason to make purchases using a wireless device • Neither the technologies nor the content exist to ensure positive wireless purchasing experience • Service providers and equipment vendors are moving ahead with developing, testing, and implementing variety of trial wireless e-business propositions E-Business Technologies

  42. Effects of Wireless Technologieson E-Business • Wireless becoming a larger part of vendor/enterprise/customer integration for B2B purchasing and production • Knowledge management simplified by wireless • Improvements in wireless technology make it cheaper/faster/more convenient to use E-Business Technologies

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