This chapter is from the book
This chapter is from the book
This chapter is from the book
Exam Preparation Tasks
Review All the Key Topics
Review the most important topics from inside the chapter, noted with the Key Topic icon in the outer margin of the page. Table 8-4 lists these key topics and the page numbers where each is found.
Table 8-4. Key Topics for Chapter 8
|
Key Topic Element |
Description |
Page Number |
|
Basic WLAN topology with a wireless router |
259 |
|
|
Basic WLAN topology with a wireless access point |
260 |
|
|
Omnidirectional antenna coverage |
261 |
|
|
Unidirectional antenna coverage |
262 |
|
|
Nonoverlapping channels in the 2.4-GHz band |
263 |
|
|
List |
Spread spectrum transmission methods |
266 |
|
Table 8-3 |
Characteristics of 802.11 standards |
268 |
|
Independent basic service set (IBSS) WLAN |
269 |
|
|
Basic service set (IBSS) WLAN |
270 |
|
|
Extended service set (ESS) WLAN |
270 |
|
|
List |
Sources of interference |
271 |
|
10–15 percent coverage overlap in coverage areas for nonoverlapping channels |
272 |
|
|
Nonoverlapping coverage cells for the 2.4-GHz band |
273 |
|
|
List |
Wireless security threats |
274 |
|
List |
Security standards and best practices |
275 |
|
IEEE 802.1x security for a WLAN |
276 |
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Complete Tables and Lists from Memory
Print a copy of Appendix C, "Memory Tables" (found on the CD), or at least the section for this chapter, and complete the tables and lists from memory. Appendix D, "Memory Table Answer Key," also on the CD, includes the completed tables and lists so you can check your work.
Define Key Terms
Define the following key terms from this chapter, and check your answers in the Glossary:
- wireless access point (AP)
- wireless router
- decibel (dB)
- omnidirectional antenna
- unidirectional antenna
- carrier sense multiple access collision avoidance (CSMA/CA)
- direct-sequence spread spectrum (DSSS)
- frequency-hopping spread spectrum (FHSS)
- Orthogonal Frequency Division Multiplexing (OFDM)
- 802.11a
- 802.11b
- 802.11g
- 802.11n
- multiple input
- multiple output (MIMO)
- channel bonding
- independent basic service set (IBSS)
- basic service set (BSS)
- extended service set (ESS)
- warchalking
- service set identifier (SSID)
- Wired Equivalent Privacy (WEP)
- Wi-Fi Protected Access (WPA)
- Wi-Fi Protected Access version 2 (WPA2)
Review Questions
The answers to these review questions are in Appendix A, "Answers to Review Questions."
-
What type of antenna, commonly used in wireless APs and wireless routers in SOHO locations, radiates relatively equal power in all directions?
- Unidirectional
- Yagi
- Parabolic
- Omnidirectional
-
When using the 2.4-GHz band for multiple access points in a WLAN located in the United States, which nonoverlapping channels should you select? (Choose three.)
- 0
- 1
- 5
- 6
- 10
- 11
- 14
-
What technology do WLANs use to determine when they gain access to the wireless media?
- SPF
- CSMA/CA
- RSTP
- DUAL
-
What IEEE 802.11 variant supports a maximum speed of 54 Mbps and uses the 2.4-GHz band?
- 802.11a
- 802.11b
- 802.11g
- 802.11n
-
Which of the following is used by IEEE 802.11n to achieve high throughput through the use of multiple antennas for transmission and reception?
- MIMO
- DSSS
- FHSS
- LACP
-
A WLAN formed directly between wireless clients (without the use of a wireless AP) is referred to as what type of WLAN?
- Enterprise mode
- IBSS
- Personal mode
- BSS
-
When extended the range for a 2.4-GHz WLAN, you can use nonoverlapping channels for adjacent coverage cells. However, there should be some overlap in coverage between those cells (using nonoverlapping channels) to prevent a connection from dropping as a user roams from one coverage cell to another. What percentage of coverage overlap is recommended for these adjacent cells?
- 5–10 percent
- 10–15 percent
- 15–20 percent
- 20–25 percent
-
If a WLAN does not require a user to provide any credentials to associate with a wireless AP and access the WLAN, what type of authentication is said to be in use?
- WEP
- SSID
- Open
- IV
-
WEP's RC4 approach to encryption uses a 24-bit string of characters added to transmitted data, such that the same plain text data frame will never appear as the same WEP-encrypted data frame. What is this string of characters called?
- Initialization vector
- Chips
- Orthogonal descriptor
- Session key
-
What standard developed by the Wi-Fi Alliance implements the requirements of IEEE 802.11i?
- TKIP
- MIC
- WEP
- WPA2