Syngress - Eleventh Hour Network+ Exam N10-004 Study Guide (11 ...

Wireless Network Concepts 61
To distinguish different wireless networks from one another, the 802.11 standard
defines the Service Set Identifier (SSID), which is considered the identity element
that “glues” various components of a WLAN together. Traffic from wireless clients
that use one SSID can be distinguished from other wireless traffic using a different
SSID. 802.11 traffic can be subdivided into three parts, which are as
follows:
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Control frames include such information as request to send (RTS), clear to
send (CTS), and acknowledgement (ACK) messages.
Management frames include beacon frames, probe request/response,
authentication frames, and association frames.
Data frames 802.11 frames that carry data, which is typically considered
network traffic, such as Internet Protocol (IP)-encapsulated frames.
IEEE 802.15 (BLUETOOTH)
Bluetooth uses the same 2.4 GHz frequency that the IEEE 802.11b and 802.11g
wireless networks use. Bluetooth characteristics are as follows:
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Bluetooth can select from up to 79 different frequencies within a radio
band.
Bluetooth networks allow clients to be connected to seven networks at the
same time.
Bluetooth devices typically have a maximum useable range of about 10 m
(33 ft.).
Bluetooth is not intended for the long ranges or high data throughput
rates.
INFRARED
Infrared is not a standard itself, but rather is the focus of the Infrared Data Association
(IrDA). The IrDA’s primary function is to create and promote a standardized
data-transmission mechanism using infrared light. Infrared characteristics are as
follows:
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Infrared devices typically can achieve a maximum data throughput of
4 Mbps.
Infrared is susceptible to light-based interference.
Infrared does not interfere in any way with RF-based wireless technologies.
There is some inherent security in infrared technology due to the fact that
an attacker would have to be in the direct path of the transmission.
WIRED EQUIVALENT PRIVACY
RF poses challenges to privacy in that it travels through and around physical
objects. Because of the nature of the 802.11 wireless LANs, the Institute of
Electrical and Electronics Engineers (IEEE) working group implemented a mechanism
to protect the privacy of the individual transmissions, known as the wired
equivalent privacy (WEP) protocol.