A comparison of wi-fi and wimax with case studies - Florida State ...
A comparison of wi-fi and wimax with case studies - Florida State ...
A comparison of wi-fi and wimax with case studies - Florida State ...
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CHAPTER ONE<br />
1. Introduction<br />
The cellphone company Nokia uses the slogan <strong>of</strong> “connecting people” in its advertising<br />
campaign. That means that technologies should be based on dem<strong>and</strong> <strong>and</strong> humility. In the <strong>fi</strong>eld <strong>of</strong><br />
the Internet, the basis <strong>of</strong> all research <strong>and</strong> innovation is geared towards making transmission <strong>of</strong><br />
communication more ef<strong>fi</strong>cient. The network technology that would eventually evolve into “the<br />
Internet” was initially developed by the military requisition called ARPANET, during late 1960s.<br />
ARPA is the acronym for Advanced Research Projects Agency an agency <strong>of</strong> the Department <strong>of</strong><br />
Defense. This network was the pioneer <strong>of</strong> the “packet s<strong>wi</strong>tch” type network. Little did the<br />
originators <strong>of</strong> ARPANET realize that this network would eventually lead to a method that could<br />
connect every PC in the world for sharing <strong>and</strong> exchanging information. The two most signi<strong>fi</strong>cant<br />
features <strong>of</strong> ARPANET were the concept <strong>of</strong> network routing <strong>and</strong> the use <strong>of</strong> packet for data<br />
transfer. In ARPANET, each computer was a node <strong>and</strong> it received the data <strong>and</strong> then routed it to<br />
next node. ARPANET was also the <strong>fi</strong>rst network using packet s<strong>wi</strong>tching to transmit data. Each<br />
node could send each packet to its destination by different paths, so it could improve the<br />
transmission to become more ef<strong>fi</strong>cient <strong>and</strong> more reliable. In the beginning, this project only<br />
included four locations, Stanford Research institute, UCLA, UC Santa Barbara <strong>and</strong> Utah<br />
University. After it was initiated successfully in 1969, the locations extended to the east coast the<br />
follo<strong>wi</strong>ng year including MIT, Harvard, Beranek <strong>and</strong> Newman. This was the world’s <strong>fi</strong>rst WAN<br />
(Wide Area Network).<br />
In 1973, the Xerox Corporation, located in California, developed the LAN (Local Area<br />
Network) for connecting PCs <strong>wi</strong>thin a local area. Therefore, the Ethernet was formed. The DIX<br />
alliance (DEC, Intel <strong>and</strong> Xerox) was the <strong>fi</strong>rst pusher <strong>of</strong> Ethernet <strong>and</strong> then transferred the patent<br />
right to IEEE (Institute <strong>of</strong> Electrical <strong>and</strong> Electronic Engineers). This move made Ethernet<br />
become popular very quickly. In 1982, DIX published Ethernet Version 2 (EV2) <strong>and</strong> later on<br />
IEEE published IEEE 802.3 CDMA/CD st<strong>and</strong>ard which was based on EV2 in 1983. Today, the<br />
IEEE 802.3 series is the most well-known Ethernet st<strong>and</strong>ard. The IEEE 802.3 is a big family that<br />
is presented in table 1-1[67][86]. They can support speeds from 10 Mbps to 1 Gbps. The<br />
increased technology causes the Internet to continually speed up.<br />
Communication technology continues to develop <strong>and</strong> an increasing number <strong>of</strong><br />
communication technologies have been implemented. However these technologies may not be<br />
compatible <strong>wi</strong>th each other. The ARPANET researchers developed a set <strong>of</strong> protocols called<br />
TCP/IP (Transmission Control protocol/Internet Protocol) to integrate networks that may be<br />
based on differing communications technologies <strong>and</strong> protocols. Internet research was not only<br />
conducted in U.S., but also in other places such as Europe, Asia, Canada <strong>and</strong> so on. Competing<br />
1