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  2. OUTLINE • Introduction • History • What is Wireless Network Communication • Difference between Wired & Wireless • Technologies • Bluetooth • Uses • Security • Types of wireless network • How WLAN works • Benefits of WLAN • Applications of WLAN • Conclusion • References

  3. INTRODUCTION • In September 1940 used a Teletype machine to send instructions for a problem set from that Model at to Complex number Calculator in New York and received results back by the same means. Linking output systems like teletypewriters to computers was an interest at the Advanced Research Projects Agency (ARPA). In 1962, J.C.R. Licklider was hired and developed a working group he called the "Intergalactic Network", a precursor to the ARPANET. • Early networks of communicating computers included the military radar system Semi-Automatic Ground Environment (SAGE), started in the late 1950s

  4. The commercial airline reservation system semi-automatic business research environment (SABRE) which went online with two connected mainframes in 1960. • In 1964, researchers at Dartmouth developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at Massachusetts Institute of Technology, a research group used a computer to route and manage telephone connections. • In 1965 first Wide Area Network was created.

  5. HISTORY • In the history of wireless technology, the demonstration of the theory of electromagnetic waves Heinrich Rudolf Hertz in 1888 was important. The theory of electromagnetic waves were predicted from the research of James Clerk Maxwell and Michael Faraday. Hertz demonstrated that electromagnetic waves could be transmitted and caused to travel through space at straight lines and that they were able to be received by an experimental apparatus. David E. Hughes, induced electromagnetic waves in a signaling system. Hughes transmitted Morse code by an induction apparatus.

  6. What is Wireless Communication? • Any form of communication that does not require the transmitter and receiver to be in physical contact. • Electromagnetic wave propagated through free-space • Radar, RF, Microwave, IR, Optical • Simplex: one-way communication (e.g., radio, TV) • Half-duplex: two-way communication but not simultaneous (e.g., push-to-talk radios) • Full-duplex: two-way communication (e.g., cellular phones)

  7. Wired Vs Wireless Mobility. • Elimination of unsightly cables. • Less installation time. • Devices can be “software” upgraded to meet new standards • Guests can connect and move around freely. Security. • Multiple Standards • Coverage - But the potential for radio interference due to weather, other wireless devices, or obstructions like walls can happen in wireless.

  8. Technologies

  9. Bluetooth • A connection between two or more portable devices without the need for cables or connectors. • The transceiver transmits and receives in a previously unused frequency band of 2.45 GHz that is available globally • The maximum range is 10 meters. • Data can be exchanged at a rate of 1 megabit per second (up to 2 Mbps in the second generation of the technology). • A frequency hop scheme allows devices to communicate even in areas with a great deal of electromagnetic interference. • Built-in encryption and verification is provided.

  10. USES • Wireless headsets for cell phones. • If the phone has Internet capability, a Bluetooth piconet can be established between the phone and nearby laptop computer to give the computer, Internet access as well. • Bluetooth enabled printers can print pictures from a Bluetooth enabled cell phone or camera. and many more….

  11. SECURITY • An 8- to 128-bit encryption key can be used to scramble Data sent over the link. • By default, most Bluetooth devices operate in unprotected "non-secure" mode called mode 1. • mode 2 leaves security up to each authorized application. • mode 3 secures the entire wireless link. • For best results, avoid encryption mode 1 (no encryption), choosing either mode 2 (encrypt unicast but not broadcast traffic) or better yet mode 3 (encrypt all traffic).

  12. TYPES OF WIRELESS NETWORK • Wireless PAN: Wireless Personal Area Networks (WPANs) interconnect devices within a relatively small area, that is generally within a person's reach. • Wireless LAN: A wireless local area network (WLAN) links two or more devices over a short distance using a wireless distribution method, usually providing a connection through an access point for Internet access.

  13. Wireless mesh network • A wireless mesh network is a wireless network made up of radio nodes organized in a mesh topology. • Wireless MAN • Wireless Metropolitan Area Networks are a type of wireless network that connects several wireless LANs. • WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard. • Wireless WAN • Wireless wide area networks are wireless networks that typically cover large areas, such as between neighboring towns and cities, or city and suburb.

  14. How WLANs Work • Wireless LANs use electromagnetic airwaves (radio and infrared) to communicate information from one point to another without relying on any physical connection. • Radio waves are often referred to as radio carriers. • The data being transmitted is superimposed on the radio carrier so that it can be accurately extracted at the receiving end. • A transmitter/receiver (transceiver) device, called an access point, connects to the wired network from a fixed location using standard Ethernet cable. • End users access the WLAN through Wireless LAN adapters. • WLAN adapters provide an interface between the client network operating system (NOS) and the airwaves (via an antenna).

  15. Benefits of WLANs • Improves productivity and service. • Installation Flexibility. • Reduced Cost-of-Ownership. • Scalability. • Mobility improves productivity and service. • Installation Speed and Simplicity

  16. Applications for Wireless LANs • Hospitals • Consulting or accounting audit teams. • In dynamic environments minimize the overhead of moves, adds, and changes with wireless LANs. • Used on Training sites at corporations and students at universities . • Easy setup in older buildings • Retail store IS managers use wireless networks to simplify frequent network reconfiguration. • Warehouse workers use wireless LANs to exchange information with central databases and increase their productivity.

  17. WiFi networks can be set up to cover whole areas of town -- though the expense has proven too much for some cities, which have disabled municipal network initiatives

  18. CONCLUSION Wireless devices continue to change rapidly. While no one is quite sure what the ultimate wireless device(s) will be, there is definitely a need to ensure that devices can function with one another. There is also the need for a truly global wireless communication infrastructure with sufficiently high bandwidth to satisfy the needs of wireless applications. The establishment of a wireless infrastructure costs a great deal.

  19. REFERENCES 1. 2. 3. 4. 5. 6. 7. 8.