The tool netstumbler detects wireless networks based what feature

Self Test Questions, Answers, and Explanations • Appendix C 773

B. WEP key

C. MAC address

A. The AP is flaky and needs to be replaced.

B. Someone is flooding your AP with traffic in a DoS attack.

774 Appendix C • Self Test Questions, Answers, and Explanations

C. Sniffing

D. Man in the Middle

B. Jamming

� B, C, D. Jamming attacks are those in which high-power RF waves are tar-geted at a wireless network installation with the hope of knocking it out of operation by overpowering it, thus Answer B is incorrect.Although your net-work has been sniffed previously to obtain the valid MAC address, you are currently being attacked using a spoofing attack, thus Answer C is incorrect.A man-in-the-middle attack is one in which an attacker sits between two com-municating parties, intercepting and manipulating both sides of the transmis-sion to suit his or her own needs, thus Answer D is incorrect.

12. The major weakness of WEP has to do with the fact that there are only a limited number of what available?

� A. Only 224IVs are available, which might seem like a lot until you realize that every frame or packet requires a unique IV.The entire stock of IVs could be exhausted in a short amount of time—perhaps just several hours—on a busy wireless network.This gives an attacker the opportunity to capture multiple frames using the same numerical IV, which is a large first step toward cracking the WEP key.

� B, C, D. Only 224IVs are available, which might seem like a lot until you realize that every frame or packet requires a unique IV.The entire stock of IVs could be exhausted in a short amount of time—perhaps just several hours—on a busy wireless network.This gives an attacker the opportunity to capture multiple frames using the same numerical IV, which is a large first step toward cracking the WEP key, thus Answers B, C and D are incorrect.

A. Open the network adapter Properties page and configure WEP from the Wireless Networks tab.

B. Install the high-security encryption pack from Microsoft.

14. In Windows XP, how do you configure WEP protection for a wireless client?

A. Open the network adapter Properties page and configure WEP from the Wireless Networks tab.

� B, C, D. Installing the high encryption pack from Microsoft just raises the encryption strength supported by the computer itself to 128 bits, thus Answer B is incorrect. Issuing the computer a digital certificate will not configure it for WEP protection in a wireless network, thus Answer C is incorrect. In about 95 percent or better of the cases,Windows XP integrates control and management of wireless network adapters into the network adapter Properties

B. You do not have the correct Windows Service Pack installed.

C. You do not configure wireless network adapters in Windows XP through manufacturer’s utilities.

Network Authentication in Windows 2000

1. You are the administrator of a mixed-mode Windows NT 4.0 domain.You have Windows 2000 and Windows NT 4.0 servers as well as Windows 2000
Professional,Windows NT Workstation, and Windows 95 client computers.What is the best network authentication method that you can reasonably hope for in your network?