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 in the chapter, noted with the key topics icon in the outer margin of the page. Table 7.6 lists a reference of these key topics and the page numbers on which each is found.
Table 7.6. Key Topics for Chapter 7
|
Key Topic Element |
Description |
Page Number |
|
APs connect WLANs and a wired Ethernet LAN |
||
|
Directional antenna signal |
||
|
List |
802.11 standards |
252 |
|
Table 7.1 |
802.11 wireless standards |
253 |
|
Table 7.2 |
RF Channels for 802.11b/g |
256 |
|
Table 7.3 |
RF Channels for 802.11a |
256 |
|
Table 7.4 |
Comparison of IEEE 802.11 standards |
259 |
|
Wireless configuration information. |
||
|
Table 7.5 |
Wireless obstacles found indoors |
265 |
|
List |
Troubleshooting access points |
266 |
|
List |
Wireless troubleshooting checklist |
267 |
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Complete the Tables and Lists from Memory
Print a copy of Appendix B, "Memory Tables," (found on the CD), or at least the section for this chapter, and complete the tables and lists from memory. Appendix C, "Memory Tables Answer Key," also on the CD, includes completed tables and lists to check your work.
Define Key Terms
Define the following key terms from this chapter, and check your answers in the Glossary.
- 802.11 a/b/g/n
- AES
- AP
- Channels
- Frequency
- Authentication
- Encryption
- Authorization
- WPA
- WPA2
- WEP
- RADIUS
- TKIP
- Omnidirectional antenna
- Directional antenna
- Beaconing
- SSID
- BSS
- ESSID
Apply Your Knowledge
Exercise 7.1 Managing Wireless Security Settings in Windows Vista
You are the network administrator for a large network that has just installed several APs. The APs are configured to use WPA2, but the client stations are not.
In this exercise, you verify the encryption method used for your wireless connection. To complete this exercise, you need a functioning wireless connection.
Estimated time: 5 minutes
Complete the following steps:
- Right-click the icon for the current wireless network connection, and click Properties.
- When selected, the Wireless Network Properties window opens. Select the Security tab.
- From the Security tab, use the drop-down menu to select WPA2.
- Select OK and the client is configured to use the wireless connection and configured with the WPA2 protocol.
Exercise 7.2 Configuring a Windows XP System to Exclusively Use a Wireless Infrastructure Connection
Configuring and managing wireless connections is an increasing part of the network administrator's role. Windows XP has built-in wizards and features to make working with wireless as easy as possible. In this exercise, we identify the setting used to determine whether a wireless connection is to be configured as an ad-hoc connection or an infrastructure connection.
This exercise assumes that the system has a wireless adapter installed.
Estimated time: 5 minutes
Complete the following steps:
- In Windows XP, choose Start, Control Panel. (Use the Control Panel in Classic View for this exercise.)
- From within the Control Panel, double-click the Network Connections Applet to open the Network Connections dialog box.
- Right-click the wireless connection, and select Properties from the menu screen. This Wireless Network Connection Properties dialog box opens.
- Select the Wireless Networks tab, and then click the Advanced button on the lower-right side of the dialog box.
- This displays a small dialog box with three options:
- Any Available Network (Access Point Preferred)
- Access Point (Infrastructure) Networks Only
- Computer-to-Computer (Ad Hoc) Networks Only
- To configure the XP system to use only an infrastructure wireless connection, select the option button next to the Access Point (Infrastructure) Networks Only option. You need to click Close for the window and click OK for the Wireless Network Connection Properties window. If you click Close and then Cancel, the changes will be dropped.
Review Questions
You can find the answers to these questions in Appendix A.
- Which of the following wireless protocols operates at 2.4GHz? (Select two.)
- 802.11a
- 802.11b
- 802.11g
- 802.11t
- Under which of the following circumstances would you change the default channel on an access point?
- When there is a channel overlap between access points
- To release and renew the SSID
- To increase the WEP security settings
- To decrease WEP security settings
- A client on your network has had no problem accessing the wireless network, but recently the client moved to a new office. Since the move she cannot access the network. Which of the following is most likely the cause of the problem?
- The SSID on the client and the AP are different.
- The SSID has been erased.
- The client has incorrect WEP settings.
- The client system has moved too far away from the access point.
- Which of the following best describes the function of beacons?
- Beacons monitor for wireless security issues.
- Beacons advertise the presence of an access point.
- Beacons prevent unauthorized access into an AP.
- Beacons prevent unauthenticated access into an AP.
- You have just purchased a new wireless access point that uses no WEP security by default. You change the security settings to use 128-bit encryption. How must the client systems be configured?
- All client systems must be set to 128-bit encryption.
- The client system will inherit security settings from the AP.
- WEP does not support 128-bit encryption.
- The client WEP settings have to be set to autodetect.
- You have just been asked to configure the security settings for a new wireless network. You want the setting that offers the greatest level of security. Which of the following would you choose?
- WEP-open
- WEP-closed
- WEP-shared
- WEP-unshared
- Which of the following best describes 802.1X?
- Port-based access control
- Wireless standard specifying 11Mbps data transfer
- Wireless standard specifying 54Mbps data transfer
- Integrity-based access control
- You are installing a wireless network solution and require a standard that can operate using either 2.4GHz or 5GHz frequencies. Which of the following standards would you choose?
- 802.11a
- 802.11b
- 802.11g
- 802.11n
- You are installing a wireless network solution that uses a feature known as MIMO. Which wireless networking standard are you using?
- 802.11a
- 802.11b
- 802.11g
- 802.11n
- In the 802.1X security framework, which of the following best describes the role of supplicant?
- To authenticate usernames and passwords
- To encrypt usernames and passwords
- The system or node requesting access and authentication to a network resource
- A control mechanism that enables or denies traffic to pass through a port
- Which of the following 802.11 standards can use the nonoverlapping channels of 1, 6, or 11? (Select two.)
- 802.11a
- 802.11b
- 802.11g
- 802.11h
- Which of the following wireless security protocols uses TKIP?
- WEP-open
- WEP-shared
- WPA
- WPA-shared
- Which of the following best describes the role of RADIUS?
- RADIUS enables a single IP address to become responsible for all remote access authentication.
- RADIUS enables a single server to become responsible for all remote access authentication.
- RADIUS encrypts all data leaving the AP.
- RADIUS encrypts all data leaving the remote system.
- Which of the following is associated with OFDM?
- 802.11n
- WEP
- WPA
- 802.11b
- A user calls to inform you that she cannot print. Upon questioning her, you determine that the she has just been moved from the second floor to the third floor. She connects to the printer via a wireless router on the first floor. You need to allow the user to print but do not want to purchase another AP or disrupt other wireless users. Which of the following might you do?
- Move the AP to allow the client system to access the network and therefore the printer.
- Search for RF interference on the 2.4GHz range.
- Change the channel.
- Configure an RF repeater to forward the wireless communications.
- You are deploying a wireless network and decide you need an antenna that provides a 360-degree dispersed wave pattern. Which of the following antennas would you select?
- Multipoint
- Unidirectional
- Omnidirectional
- Dispersal
- You are working with a wireless network that uses channel 1 (2412MHz). What RF range would be used if you switched to channel 3?
- 2417
- 2422
- 2427
- 2408
- You are the network administrator for a small company. Recently you added two remote clients who access the network through an AP. To increase security you decide you need to keep the network name hidden. Which of the following could you do?
- Enable WEP broadcast
- Disable WEP broadcast
- Enable secure SSID broadcast
- Disable SSID broadcast
- Which of the following wireless standards specifies an RF of 5GHz?
- 802.11a
- 802.11b
- 802.11g
- 802.11g
- What is the maximum network speed defined by the 802.11b standard?
- 100Mbps
- 5.5Mbps
- 11Mbps
- 10Mbps