Chapter 8

Wireless signals experience attenuation. T/F
T
Spread spectrum is a popular way of making wireless transmissions more secure. T/F
T
Wireless networks are laid out using the same topologies as wired networks. T/F
F
An ad hoc arrangement would work well for a WLAN with many users. T/F
F
WiMAX is defined by the IEEE 802.11 standard. T/F
F
In wireless communication, to exchange information, two antennas must be tuned to the same __.
Frequency
A directional antenna issues wireless signals along a(n) __ direction.
Single
In __, a wireless signal splits into secondary waves when it encounters an obstruction.
Diffraction
__ is a significant problem for wireless communications because the atmosphere is saturated with electromagnetic waves.
Interference
In __ wireless systems, the transmitting antenna focuses its energy directly toward the receiving antenna which results in a point-to-point link.
Fixed
In the case of connecting two WLANs, access points could be as far as __ feet apart.
1000
In __ scanning, the station transmits a special frame, known as a probe, on all available channels within its frequency range.
Active
A unique characteristic of the 802.11 data frame is its __ field.
Sequence Control
The average geographic range for an 802.11a antenna is __ meters.
20
__ is the least popular WLAN standard
802.11a
An 802.11g antenna has a geographic range of __ meters.
100
__ may use either the 2.4-GHz or 5-GHz frequency range.
802.11n
__ is an 802.11n feature that allows two adjacent 20-MHz channels to be combined to make a 40-MHz channel.
Channel Bonding
__ is an 802.11n network feature allowing the combination of multiple frames into one larger frame.
Frame Aggregation
__ is a command-line function for viewing and setting wireless interface parameters and it is common to nearly all versions of Linux and UNIX.
iwconfig
If intermittent and difficult-to-diagnose wireless communication errors occur, __ might be the culprit.
Interference
Most satellites circle the Earth __ miles above the equator in a geosynchronous orbit.
22,300
__ satellites are the type used by the most popular satellite data service providers.
Geosynchronous Orbiting
Which satellites transmit and receive signals in the 12 to 18 GHz band?
Ku-
Clients are able to exchange signals with satellites as long as they have a __ path.
Line Of Sight
To establish a satellite Internet connection, each subscriber must have a __.
Dish Antenna
The use of multiple frequencies to transmit a signal is known as __ technology.
Spread-Spectrum
The __ is a unique character string used to identify an access point.
SSID
A(n) __ assesses client requirements, facility characteristics, and coverage areas to determine an access point arrangement that will ensure reliable wireless connectivity within a given area.
Site Survey
802.11b and g signals can extend a maximum of __ feet and still deliver data reliably.
330
__ means that satellites orbit the Earth at the same rate as the Earth turns.
Geosynchronous Orbit
Uses the 2.4-2.4835-GHz frequency range.
802.11b
The locations of the transmitter and receiver do not move.
Fixed Wireless
Uses channels in the 5-GHz band and provides a maximum theoretical throughput of 54 Mbps.
802.11a
Accepts wireless signals from multiple nodes and retransmits them to the rest of the network.
Access Point
Represents the connection between a carrier’s antenna and a client’s transceiver.
Downlink
Uses the 2.4-GHz frequency band and provides a maximum theoretical throughput of 54 Mbps.
802.11g
The receiver can be located anywhere within the transmitter’s range.
Mobile Wireless
Refers to the connection between a client’s transceiver and the carrier’s antenna.
Uplink
Boasts a maximum throughput of 600 Mbps.
802.11n