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Networking Fundamentals
■ A wireless network that contains one or more Wireless Access Points is
arranged in infrastructure mode.
■ A wireless network that does not contain a Wireless Access Point (WAP) is
arranged in ad hoc mode.
■ The IEEE 802.11a standard describes wireless networks operating at 5 GHz
with a maximum data rate of 54 Mbps.
■ The IEEE 802.11b standard describes wireless networks operating at 2.4 GHz
with a maximum data rate of 11 Mbps.
■ The IEEE 802.11g standard describes wireless networks operating at either
2.4 GHz or 5 GHz with a maximum data rate of 54 Mbps.
■ IEEE 802.11n standard operates at 5 GHZ and 2.4 GHz with a maximum data
rate of 300 Mbps to 600 Mbps.
■ Multiple Input Multiple Output (MIMO) uses two or more streams of data
transmission to increase data throughput and the range of the wireless
network. MIMO is described in the IEEE 802.11n standard.
■ Spatial multiplexing is the transmission of two or more streams of data
simultaneously.
■ IEEE 802.15 standard describes the use of Wireless Personal Area Networks
(WPANs).
■ Wireless networks specifi ed under the IEEE 802.11 standard use Carrier
Sense Multiple Access with Collision Avoidance (CSMA/CA) as the media
access method.
■ Bluetooth is a standard developed by a group of manufacturers to allow their
devices to interoperate. Bluetooth is recognized by the 802.11 standard and is
used for short-range data transfer applications using the 2.4-GHz radio band.
■ Infrared is commonly used for point-to-point transmission between two
devices such as a personal digital assistant and a PC.
■ Satellite communications experience propagation delay because of the great
distance a signal must travel.
■ Wireless technology can be cost-effective when compared with cable-based
network media.
■ A disadvantage of employing wireless technology is security.
■ A Service Set Identifi er (SSID) is similar in function to a workgroup name or
domain name and must be assigned to a Wireless Access Point (WAP).
■ Wireless networks are not secure when default settings are used for the
confi guration.
■ Wireless encryption keys should be changed on a regular basis to maintain a
high degree of security.
Review Questions
Answer the following questions on a separate sheet of paper. Please do not write in this book.
1. A(n) _____ is an electromagnetic wave of a set frequency that is used to carry
data in radio wave- and microwave-based networks.
2. What is modulation?