5 Wifi What is the wifi? Wireless fidelity ( wifi). History : it is invented in 1991 by NCR corporation. it is used for cashier system. Its name was WaveLan with speed 1-2Mbps.
6 Who invented wifi?The father of wifi is Vic Hayes.
7 Wifi refers to a type of Ethernet specified under the IEEE 802 Wifi refers to a type of Ethernet specified under the IEEE a and b standards for LANs operating in the 5 – 2.4 GHz unlicensed frequency bands respectively.
8 How does it work ?WiFi uses radio waves to transmit the information to and from the internet or your computer network. When a website wants to communicate with your computer it sends the information to your modem as it does now on your wired connection, then the information is passed on to a wireless router, which then converts it to radio waves and beams it to your computer.
9 What are WiFi Hotspots?Hotspots are areas where WiFi radio signals can be picked up by your computer. At home, a wireless router (such as the one shown at right) does the job to make your entire home a hotspot.
11 wimaxWhat is the wimax ?Worldwide interoperability for microwave access (WiMAX).Definition.
12 Goal of wimaxProvide high speed internet access to home and business subscriber.
13 How does it work ? Infrastructure: 1 access point 2 base station (BS) 3 subscribers stations( SS)
14 Tower (BS): similar to a cell phone tower Tower (BS): similar to a cell phone tower. Can provide to coverage to a very large area( km).A wimax receiver: the receiver and antenna could be small box or PCMCIA card or could be built in a laptop.
15 During communication all information come from SS to the BS and retransmit to the right SS.
16 Comparing Range and data rate : Wi-Fi : around 30 meters. WiMAX : In theory 112 Km.expected value : 2 Km. ( under conditions).Wi-Fi : around 54 Mbit.WiMAX : In theory 70 Mbit.expected value : 10 Mbit.