Smart Phone and Next Generation Mobile Computing

158 Smart Phone and Next-Generation Mobile Computing

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Power control — This field is set to 1 if the transmission station is

in sleep mode; it is set to 0 if it is in active mode.

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More data — Indicates that the transmitter has more data for the

intended receiver. If the transmitter is an access point, the field

informs a station in sleep mode that more data are buffered at the

access point.

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WEP — This field is set to 1 to indicate that the frame body is

encrypted using the WEP algorithm (described later).

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Order — This field is set to 1 to inform the receiver that a number

of fames are in strict order.

3.10.3 Beacon Frame

802.11 beacon frames are used for a number of purposes including

time synchronization, power saving, and access point discovery. Like