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11 Cards in this Set
- Front
- Back
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Mobile Computing |
A real-time, wireless connection between a mobile device and other computing environments, such as the internet or an intranet |
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Advantages to wireless devices |
1. small enough to easily carry or wear 2. Sufficient computing power to perform productive tasks 3. Can communicate wirelessly with the internet and other devices. |
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Dematerialization types |
Books, compass, camera, calculator etc. |
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Electronic magnetic spectrum Microwaves |
Wifi. blue tooth. Satellite coma. High bandwidth. Relatively inexpensive.
Must have unobstructed line of sight. Environmental interference. |
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Electromagnetic spectrum Radio |
Walkie talkie. Baby monitor. High bandwidth. Signals pass through walls. Inexpensive. Easy.
Electrical interference problems. Susceptible to snooping. |
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Electromagnetic spectrum satellite. |
High bandwidth. Large coverage area. Expensive. Unobstructed line of sight. Propagation delay. Need encryption. |
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Three types of satellites circling earth. |
GEO - Geostationary earth orbit MEO - medium earth orbit LEO - low earth orbit. |
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Geostationary earth orbit |
22,300 miles above earth .25 second delay Longest orbital life Used for TV Most expensive |
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Medium earth orbit |
6,434 miles above earth Moves relative to point on earth Negligible delay Moderate orbital life (6-12 yrs) Used for global positional systems |
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Low earth orbit |
400-700 miles above earth Moves rapidly in relation to point. Negligible transmission Shortest orbital life Large number needed for global coverage. Least expensive to build |
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4 major challenges to wireless networks. |
Rogue access Evil twin attack Hotspotter War driving Eavesdropping Radio Frequency Jamming |
