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A comparison of wi-fi and wimax with case studies - Florida State ...

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since the January 2006. The population coverage is more than 90%, but the geographic coverage<br />

is only about 50%. The total number <strong>of</strong> APs are about 4200.<br />

5.2.2. Implementation<br />

The WiFly infrastructure installation was split in three stages. The <strong>fi</strong>rst stage was to cover<br />

the 30 MRT (Mass Rapid Transit) stations <strong>and</strong> the surrounding areas, including the underground<br />

shopping streets. This stage was <strong>fi</strong>nished in May 2005. The second stage included 42 main city<br />

arteries, shopping districts, c<strong>of</strong>fee shops, <strong>and</strong> the rest <strong>of</strong> MRT stations <strong>and</strong> so on. There were<br />

about 2000 APs that were installed in this stage. In the third stage, there were 9 city hospitals, 53<br />

libraries, 12 Taipei administrative buildings <strong>and</strong> 600 7-11s (chained convenient stores) included.<br />

The <strong>fi</strong>nal stage was <strong>fi</strong>nished in July 2006. More than 4200 APs were used, <strong>and</strong> up to 90% <strong>of</strong> the<br />

population was covered. This was a br<strong>and</strong> new world record. [72]<br />

The WiFly uses Nortel Wireless Mesh Network as its fundamental model. Two components,<br />

Wireless Gateway 7250 <strong>and</strong> Wireless Access Point 7220, were used for this model. In this<br />

network, the connection between APs is 802.11a <strong>and</strong> the connection between AP <strong>and</strong> end users<br />

is 802.11b/g. Since there is no need to <strong>wi</strong>re every AP in the network, the cost <strong>of</strong> installing <strong>wi</strong>red<br />

network from gateway to AP <strong>and</strong> AP to AP can be eliminated. [72]<br />

The Nortel Wireless Mesh Network is a solution <strong>of</strong> installing the outdoor <strong>and</strong> indoor Wi-Fi<br />

network. It is scalable <strong>and</strong> secure. An ISP can use it to provide <strong>wi</strong>reless internet service <strong>and</strong><br />

companies can use it to build inner private networks. The network contains three components; a<br />

<strong>wi</strong>reless access point, <strong>wi</strong>reless a gateway <strong>and</strong> a <strong>wi</strong>reless mesh management platform. Figure 5-<br />

10[75], Figure 5-11[75], Table 5-5[75]<br />

There are two models <strong>of</strong> APs, Wireless AP 7220 <strong>and</strong> Wireless AP 7215. The WAP 7220 is<br />

an outdoor <strong>and</strong> indoor-type AP <strong>and</strong> the WAP 7215 is an indoor-type AP. Figure 5-12[75]. The<br />

WAP 7220s can be connected together to cooperate for improving system performance. WAP<br />

7215 only works in indoor locations. It can connect to either <strong>wi</strong>red or <strong>wi</strong>reless networks. WAP<br />

7220 <strong>and</strong> WAP 7215 also can cooperate together to form the <strong>wi</strong>reless mesh network. The<br />

<strong>wi</strong>reless gateway has two models as well; Wireless Gateway 7250 <strong>and</strong> Wireless Gateway 7240.<br />

The WG 7250 can support 10/100 Ethernet interface <strong>and</strong> 120 WAPs. The WG 7240 also has<br />

10/100 Ethernet interface but only supports 10 WAPs. The Wireless Mesh Management System<br />

provides a communication interface for Nortel’s <strong>wi</strong>red <strong>and</strong> <strong>wi</strong>reless network products. [75]<br />

75

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