Wireless Networking - GoCertifycdn.gocertify.com/images/downloads/tracy-network-ch09.pdf · Wireless Networking ... You are implementing an 802.11n wireless network for a small business

CertPrs8 / CompTIA Network+® Certification Practice Exams (Exam N10-005) / Tracy / 881-6 / Chapter 9 Blind Folio 181

9Wireless Networking

CertifiCation objeCtives

q 2.2 Given a scenario, install and configure a wireless network.

q 2.4 Given a scenario, troubleshoot common wireless problems.

q 3.3 Compare and contrast different wireless standards.

q 5.1 Given a scenario, implement appropriate wireless security measures.

q 5.4 Explain common threats, vulnerabilities, and mitigation techniques.

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182 Chapter 9: Wireless Networking

CertPrs8 / CompTIA Network+® Certification Practice Exams (Exam N10-005) / Tracy / 881-6 / Chapter 9

QuestionsWireless networks provide a degree of mobility and flexibility that modern network users demand. However, a wireless network must be implemented correctly to provide adequate performance while preventing network security issues. For example, you must manage the placement and power level of wireless networking components to provide adequate service to your users. At the same time, you must prevent the signal from leaking outside your organization. In addition, you must implement encryption and authentication mechanisms to ensure that only authorized users are able to access the wireless network.

You are implementing a wireless network in an office suite. Due to the rectangular shape of the 1. building, you need to implement a single wireless access point in the center of the office suite along with four additional wireless access points in each corner. What should you do? (Choose two.)

Implement a WAP with an omni-directional antenna in the center of the office complex.A. Implement a WAP with a semi-directional antenna in each corner of the office complex.B. Implement a WAP with a highly-directional antenna in the center of the office complex.C. Implement a WAP with a semi-directional antenna in the center of the office complex.D. Implement a WAP with an omni-directional antenna in each corner of the office complex.E.

You’ve discovered that the signal from your wireless network is emanating some distance out 2. into the parking lot of your facility. What can you do to stop this? (Choose three.)

Implement wireless repeaters at strategic locations within your building.A. Relocate the wireless access point to a central location in your building.B. Increase the gain on the wireless access point antenna.C. Reduce the power level of the wireless access point.D. Implement a Faraday cage on the exterior of your building.E. Implement omni-directional wireless access points.F.

Which type of wireless network does not use a wireless access point?3. InfrastructureA. BusB. StarC. Ad hocD.

Which wireless networking standard runs at a frequency of 5 GHz? (Choose two.)4. 802.11aA. 802.11bB. 802.11gC. 802.11nD. 802.11zE.

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Questions 183


You’ve discovered an older laptop in your equipment closet that has in integrated 802.11b 5. wireless network adapter. Your organization uses 802.11n wireless access points to provide wireless connectivity to your network. What must you do to connect this device to the network?

Disable the integrated 802.11b adapter and install an 802.11n USB wireless network A. adapter.Disable the integrated 802.11b adapter and install an 802.11g USB wireless network B. adapter.Install a wireless bridge and connect the integrated 802.11b adapter to the 802.11b side of C. the bridge.Connect the integrated 802.11b adapter directly to the 802.11n wireless network.D.

Which technologies allows the 802.11n standard to provide dramatically more wireless 6. bandwidth than that available with 802.11b and 802.11g? (Choose two.)

Lempel-Ziv (LZ) compressionA. Time-division multiplexingB. 3DES data encryptionC. MIMOD. Channel bondingE.

You are implementing an 802.11n wireless network for a small business in a rented office suite 7. within a large, multitenant office complex. You are experiencing significant interference in the wireless network, causing dropped connections. You’ve discovered that the 2.4 GHz cordless phone system used in the office is set to use channel 3. You also discovered that neighboring tenants are using channels 1 and 5 for their 802.11x wireless networks. What should you do?

Set your wireless access point to use channel 2.A. Set your wireless access point to use channel 4.B. Set your wireless access point to use channel 7.C. Set your wireless access point to use channel 3.D.

A small business has hired you to manage its 802.11g wireless network. Upon investigation, you 8. find that 128-bit WEP is being used to secure transmissions on the wireless network. Which components comprise the encryption keys used on this network? (Choose two.)

24-bit initialization vectorA. 40-bit encryption keyB. 48-bit initialization vectorC. 104-bit encryption keyD. 80-bit encryption keyE.

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Which security standard uses the AES-CCMP algorithm to secure data on a wireless network?9. WEPA. WPA2B. WPAC. WAPID.

You are implementing a new wireless network for a financial services firm. You need to ensure 10. that the network is as secure as possible. What should you do? (Choose two.)

Implement WEP encryption on wireless access points and all client systems that will A. connect to them.Hide the SSID.B. Implement MAC address filtering.C. Implement WPA encryption on wireless access points and all client systems that will D. connect to them.Use omni-directional antennae on the wireless access points and locate them along the E. exterior walls of the firm’s physical structure.

A nefarious individual has used Kismet on his laptop to determine the SSID of a public access 11. WAP at an airport. Using this information, he has set up a rogue access point and web server on a laptop within the airport using the same SSID. On the web server, he has created bogus web pages that look like the pages used by several large banks and credit card companies. These pages are used to capture bank and credit card account information and account credentials. What kind of wireless exploit is in use in this scenario?

Evil twinA. WPA crackingB. War chalkingC. War drivingD.

Which security weakness is found within the WEP encryption scheme and makes it relatively 12. easy to crack?

The DES encryption used by WEP is relatively easy to crack.A. The RSA encryption used by WEP is relatively easy to crack.B. Short passphrases using words found in the dictionary can be cracked using a dictionary attack.C. The 24-bit IVs are reused and transmitted in clear-text.D.

Which mechanism can be used with WPA security to encapsulate Extensible Authentication 13. Protocol (EAP) information within an encrypted SSL/TLS tunnel?

Lightweight Extensible Authentication Protocol (LEAP)A. Protected Extensible Authentication Protocol (PEAP)B. Temporal Key Integrity Protocol (TKIP)C. Extensible Authentication Protocol-MD5 (EAP-MD5)D.

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Questions 185


The wireless users located in a portable office building situated next to your organization’s 14. main physical structure are complaining of slow data transfers over the network. Given that your organization uses an 802.11n wireless network with WAPs implemented within the main physical structure, what should you do? (Choose two.)

Implement MAC address filtering.A. Move the users closer to the WAP to see if the signal strength improves.B. Upgrade the users’ computers to 802.11a network interfaces.C. Implement an additional WAP in the location where the users work.D. Change the channel used by the WAP nearest the users to a higher numbered channel.E.

Your 802.11n wireless network is experiencing a significant amount of latency. You’ve used 15. the IPERF utility to determine that your wireless network is experiencing a significant number of packets arriving out of order, arriving late, and being completely lost. What should you do? (Choose two.)

Check for sources of interference, such as microwave ovens or 2.4 GHz cordless phones.A. Verify that all devices on the wireless network are using the correct encryption mechanism.B. Try using a different channel on the WAP to reduce interference from other 2.4 GHz devices.C. Verify that wireless devices are not using mismatched SSIDs.D. Move the WAP’s antenna to a lower physical location.E.

A user has reported that he can’t connect to your organization’s 802.11n wireless network from 16. his newly issued laptop computer. The user works in a location at which you know a good wireless signal is available. In addition, none of his co-workers are having trouble connecting to the wireless network. The user checked the documentation that came with his laptop and verified that it has an integrated wireless adapter and that it is enabled. What should you do? (Choose three.)

Verify that the user is using the correct SSID when connecting.A. Install an 802.11n wireless USB adapter in the laptop. B. Check to see if MAC filtering is in use on the WAP.C. Change the channel used by the WAP to eliminate interference from other 2.4 GHz D. devices.Check for surfaces or objects that might be causing the wireless network signal to bounce.E. Verify that the user has configured the wireless adapter to use the correct wireless F. encryption mechanism.

Given optimal wireless conditions, which wireless networking standard provides the longest range?17. 802.11aA. 802.11bB. 802.11gC. 802.11nD.

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Which wireless networking standard is limited to a maximum bitrate of 11 Mbps?18. 802.11aA. 802.11bB. 802.11gC. 802.11nD.

Which wireless security mechanism uses a preshared key (PSK)?19. WEPA. WPA2 EnterpriseB. WPA PersonalC. WAPID.

The Marketing workgroup in your organization decided that they need a stronger wireless signal 20. in their workspace to support the tablet devices they are using to develop a new marketing app. To do this, they purchased a WAP and plugged it into an open network jack within an empty cubicle. Which term best describes the security risk in this scenario?

Rogue access pointA. Evil twinB. War drivingC. Data emanationD.

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Quick Answer Key 187

CertPrs8 / CompTIA Security+™ Certification Practice Exams (Exam SY0-301) / Lachance / 120-4 / Chapter 9

QuiCk answer key

1. A, B

2. B, D, E

3. D

4. A, D

5. D

6. D, E

7. C

8. A, D

9. B

10. B, C

11. A

12. D

13. B

14. B, D

15. A, C

16. A, C, F

17. D

18. B

19. C

20. A

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in-Depth answers You are implementing a wireless network in an office suite. Due to the rectangular shape of the 1.

building, you need to implement a single wireless access point in the center of the office suite along with four additional wireless access points in each corner. What should you do? (Choose two.)

Implement a WAP with an omni-directional antenna in the center of the office complex.A. Implement a WAP with a semi-directional antenna in each corner of the office complex.B. Implement a WAP with a highly-directional antenna in the center of the office complex.C. Implement a WAP with a semi-directional antenna in the center of the office complex.D. Implement a WAP with an omni-directional antenna in each corner of the office complex.E.

®3 A and B. The goal of wireless antenna placement is to achieve the best coverage without excessive signal emanation outside the facility. Therefore, an omni-directional antenna in the center of the rectangular suite would provide the best coverage. Using semi-directional antennae in each corner would fill in the dead spots left by the omni-directional antenna but reduce signal emanation outside.

®̊ C, D, and E are incorrect. C and D are incorrect because using a semi- or highly-directional antenna in the center of the complex would provide poor coverage in a rectangular office suite. E is incorrect because using omni-directional antennae in each corner of the office would excessively emanate the wireless signal outside the facility.

You’ve discovered that the signal from your wireless network is emanating some distance out 2. into the parking lot of your facility. What can you do to stop this? (Choose three.)

Implement wireless repeaters at strategic locations within your building.A. Relocate the wireless access point to a central location in your building.B. Increase the gain on the wireless access point antenna.C. Reduce the power level of the wireless access point.D. Implement a Faraday cage on the exterior of your building.E. Implement omni-directional wireless access points.F.

®3 B, D, and E. You could employ several strategies to reduce signal emanation. One is to relocate the WAP to the center of your facility. Another is to reduce the power level of your WAP. However, depending upon the layout of your building, you may need to implement additional directional WAPs to cover dead spots created by the reduced signal strength. Many organizations with very high security requirements implement

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In-Depth Answers 189


a metal mesh around the exterior of their buildings to form a Faraday cage that stops signal emanation completely. However, it will also block cell phone signals.

®̊ A, C, and F are incorrect. A is incorrect because wireless repeaters would likely increase signal emanation unless they used directional antennae. C and F are incorrect because they would both likely increase signal emanation rather than reduce it.

Which type of wireless network does not use a wireless access point?3. InfrastructureA. BusB. StarC. Ad hocD.

®3 D. An ad hoc wireless network allows wireless hosts to connect directly to one another without the use of a WAP. This essentially forms a wireless mesh network topology.

®̊ A, B, and C are incorrect. A is incorrect because infrastructure wireless networks use a WAP. B is incorrect because wireless Ethernet networks still function as a logical bus, regardless of whether they run in infrastructure or ad hoc mode. C is incorrect because a wireless network that uses a star topology would require a WAP as a central connecting point.

Which wireless networking standard runs at a frequency of 5 GHz? (Choose two.)4. 802.11aA. 802.11bB. 802.11gC. 802.11nD. 802.11zE.

®3 A and D. 802.11a is an older wireless networking standard that operates in the 5 GHz frequency range and transmits data at 54 Mbps. 802.11a devices are incompatible with 802.11b and 802.11g devices as these standards all operate in the 2.4 GHz frequency range. However 802.11a devices are usually compatible with 802.11n devices, because the 802.11n standard operates at either 2.4 or 5 GHz.

®̊ B, C, and E are incorrect. B and C are incorrect because the 802.11b and 802.11g standards all operate in the 2.4 GHz frequency range. E is incorrect because the 802.11z standard specifies extensions to Direct Link Setup.

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You’ve discovered an older laptop in your equipment closet that has in integrated 802.11b 5. wireless network adapter. Your organization uses 802.11n wireless access points to provide wireless connectivity to your network. What must you do to connect this device to the network?

Disable the integrated 802.11b adapter and install an 802.11n USB wireless network A. adapter.Disable the integrated 802.11b adapter and install an 802.11g USB wireless network adapter.B. Install a wireless bridge and connect the integrated 802.11b adapter to the 802.11b side of C. the bridge.Connect the integrated 802.11b adapter directly to the 802.11n wireless network.D.

®3 D. All 802.11b/g/n devices are compatible with each other. Therefore, you can connect the integrated 802.11b wireless network interface in the laptop directly to the 802.11n wireless network. However, the adapter will run at a rather sedate 11 Mbps.

®̊ A, B, and C are incorrect. A will work; it’s incorrect, however, because the integrated 802.11b wireless network interface in the laptop can connect directly to the 802.11n wireless network. B will also work, but it’s incorrect because the integrated 802.11b wireless network interface in the laptop can connect directly to the 802.11n wireless network. C is incorrect because a bridge isn’t necessary to connect an 802.11b wireless network to an 802.11n network.

Which technologies allows the 802.11n standard to provide dramatically more wireless 6. bandwidth than that available with 802.11b and 802.11g? (Choose two.)

Lempel-Ziv (LZ) compressionA. Time-division multiplexingB. 3DES data encryptionC. MIMOD. Channel bondingE.

®3 D and E. The 802.11n wireless networking standard employs multiple input multiple output (MIMO) and channel bonding to increase bandwidth. MIMO involves the use of multiple antennae, while channel bonding allows data to be transferred over two channels simultaneously.

®̊ A, B, and C are incorrect. A is incorrect because 802.11n does not compress data to increase throughput. B is incorrect because 802.11n does not use time-division multiplexing. It does, however, use space-division multiplexing to implement MIMO. C is incorrect because 802.11n does not specify the use of 3DES encryption (nor would the use of encryption increase bandwidth).

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You are implementing an 802.11n wireless network for a small business in a rented office suite 7. within a large, multitenant office complex. You are experiencing significant interference in the wireless network, causing dropped connections. You’ve discovered that the 2.4 GHz cordless phone system used in the office is set to use channel 3. You also discovered that neighboring tenants are using channels 1 and 5 for their 802.11x wireless networks. What should you do?

Set your wireless access point to use channel 2.A. Set your wireless access point to use channel 4.B. Set your wireless access point to use channel 7.C. Set your wireless access point to use channel 3.D.

®3 C. Because there is frequency overlap between channels within the 2.4 GHz range, you need to select a channel far away from those already in use. In this example, channels 1, 3, and 5 are used by nearby equipment. Therefore setting your WAP to use channel 7 should eliminate interference from these devices.

®̊ A, B, and D are incorrect. A is incorrect because there is overlap between the frequencies used by channels 1 (2.3995–2.4245 GHz) and 2 (2.4045–2.4295 GHz) in the 2.4 GHz range. B is incorrect because there is overlap between the frequencies used by channels 3 (2.4095–2.4345 GHz) and 4 (2.4145–2.4395 GHz) in the 2.4 GHz range. D is incorrect because channel 3 is already in use by the cordless phone system. If set to the same channel, the wireless network will work only until someone in the office uses the telephone.

A small business has hired you to manage its 802.11g wireless network. Upon investigation, you 8. find that 128-bit WEP is being used to secure transmissions on the wireless network. Which components comprise the encryption keys used on this network? (Choose two.)

24-bit initialization vectorA. 40-bit encryption keyB. 48-bit initialization vectorC. 104-bit encryption keyD. 80-bit encryption keyE.

®3 A and D. 128-bit WEP security uses a 24-bit initialization vector and then a 104-bit encryption key. 64-bit WEP security uses the same 24-bit initialization vector, but uses a 40-bit key for encryption only.

®̊ B, C, and E are incorrect. B is incorrect because a 40-bit encryption key is used by 64-bit WEP security. C is incorrect because the initialization vector used by WEP is 24-bits, not 48 bits, long. E is incorrect because WEP uses either 40- or 104-bit encryption keys.

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Which security standard uses the AES-CCMP algorithm to secure data on a wireless network?9. WEPA. WPA2B. WPAC. WAPID.

®3 B. The key difference between WPA and WPA2 is the inclusion of AES-CCMP to secure data on the wireless network. WPA2 is considered more secure than WPA and much more secure than WEP.

®̊ A, C, and D are incorrect. A and C are incorrect because neither WEP nor WPA use AES-CCMP to secure data. D is incorrect because WAPI is a wireless security standard defined by the government of China that uses SMS4 symmetric encryption instead of AES-CCMP.

You are implementing a new wireless network for a financial services firm. You need to ensure 10. that the network is as secure as possible. What should you do? (Choose two.)

Implement WEP encryption on wireless access points and all client systems that will A. connect to them.Hide the SSID.B. Implement MAC address filtering.C. Implement WPA encryption on wireless access points and all client systems that will D. connect to them.Use omni-directional antennae on the wireless access points and locate them along the E. exterior walls of the firm’s physical structure.

®3 B and C. You can configure each WAP not to broadcast the SSID of the network to make it more difficult to locate. Implementing MAC address filtering to control which hosts are allowed to connect will help increase the security of the wireless network. Be aware that these measures provide only a basic level of security. Encryption and authentication should be enabled on the wireless network. Because of the sensitive nature of the information on this network, you should also consider implementing a VPN to restrict access to the wired network from the wireless network.

®̊ A, D, and E are incorrect. A is incorrect because WEP encryption is notoriously weak and can be compromised with relative ease. D is incorrect because the sensitive nature of the data on this network would dictate the use of WPA2 or (better yet) WPA-Enterprise encryption. E is incorrect because omni-directional antennae installed on the exterior walls of the physical structure would emanate a strong wireless signal outside the firm.

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A nefarious individual has used Kismet on his laptop to determine the SSID of a public access 11. WAP at an airport. Using this information, he has set up a rogue access point and web server on a laptop within the airport using the same SSID. On the web server, he has created bogus web pages that look like the pages used by several large banks and credit card companies. These pages are used to capture bank and credit card account information and account credentials. What kind of wireless exploit is in use in this scenario?

Evil twinA. WPA crackingB. War chalkingC. War drivingD.

®3 A. This is an example of an evil twin wireless exploit. The victims connect to the rogue WAP thinking it is the airport’s public access WAP. Then they send their confidential information to the criminal’s web server, thinking they are logging into their legitimate bank or credit card accounts.

®̊ B, C, and D are incorrect. B is incorrect because WPA cracking involves using software to capture packets transmitted on the wireless network and crack the WPA encryption used to secure them. C and D are incorrect because war chalking and war driving involve searching out wireless network signals and marking their location either on a map or on the sidewalk with chalk using special symbols to identify the characteristics of the network.

Which security weakness is found within the WEP encryption scheme and makes it relatively 12. easy to crack?

The DES encryption used by WEP is relatively easy to crack.A. The RSA encryption used by WEP is relatively easy to crack.B. Short passphrases using words found in the dictionary can be cracked using a dictionary attack.C. The 24-bit IVs are reused and transmitted in clear-text.D.

®3 D. WEP wireless security uses an RC4 wireless stream cipher, which has a key weakness of reusing 24-bit IVs and transmitting them as clear-text in the header of packets containing a WEP-encrypted payload. If enough packets are captured (around 10,000 or so), software can be used to crack the complete encryption key, thus exposing the encrypted network transmissions.

®̊ A, B, and C are not correct. A and B are incorrect because WEP does not use DES or RSA encryption, although RC4 was initially developed by the RSA organization. C is incorrect because the use of short passphrases containing dictionary terms is a weakness associated with the WPA encryption mechanism.

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Which mechanism can be used with WPA security to encapsulate Extensible Authentication 13. Protocol (EAP) information within an encrypted SSL/TLS tunnel?

Lightweight Extensible Authentication Protocol (LEAP)A. Protected Extensible Authentication Protocol (PEAP)B. Temporal Key Integrity Protocol (TKIP)C. Extensible Authentication Protocol-MD5 (EAP-MD5)D.

®3 B. The PEAP authentication mechanism was created in cooperation by Cisco, Microsoft, and RSA Security. PEAP encapsulates EAP authentication information within an encrypted SSL/TLS tunnel. PEAP provides better security and is preferred over other mechanisms such as LEAP and EAP-MD5.

®̊ A, C, and D are incorrect. A is incorrect because LEAP uses passwords only. No digital certificates or any other type of PKI mechanism is used, so some information is sent as clear-text. C is incorrect because TKIP is a protocol designed to improve upon WEP’s key-based flaws. It provides dynamic key generation and rotation, ensuring that each packet gets a unique encryption key. D is incorrect because EAP-MD5 is an early authentication mechanism that offers very little security. It uses an MD5 hash to secure data, which is vulnerable to a variety of attacks.

The wireless users located in a portable office building situated next to your organization’s 14. main physical structure are complaining of slow data transfers over the network. Given that your organization uses an 802.11n wireless network with WAPs implemented within the main physical structure, what should you do? (Choose two.)

Implement MAC address filtering.A. Move the users closer to the WAP to see if the signal strength improves.B. Upgrade the users’ computers to 802.11a network interfaces.C. Implement an additional WAP in the location where the users work.D. Change the channel used by the WAP nearest the users to a higher numbered channel.E.

®3 B and D. The bandwidth available to wireless network client decreases as the distance from the WAP increases. In this scenario, the users are probably too far away to get a good signal. Moving the users closer to the WAP or implementing an additional WAP within the portable structure will probably fix the issue.

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®̊ A, C, and E are incorrect. A is incorrect because MAC address filtering controls who can and who can’t connect to the wireless network. It does not improve signal strength. C is incorrect because the 802.11a is an older, seldom implemented network standard that would not fix the issue in this scenario. E is incorrect because interference caused by a misconfigured channel setting on the WAP would affect all wireless users, not just those working in the auxiliary building.

Your 802.11n wireless network is experiencing a significant amount of latency. You’ve used 15. the IPERF utility to determine that your wireless network is experiencing a significant number of packets arriving out of order, arriving late, and being completely lost. What should you do? (Choose two.)

Check for sources of interference, such as microwave ovens or 2.4 GHz cordless phones.A. Verify that all devices on the wireless network are using the correct encryption mechanism.B. Try using a different channel on the WAP to reduce interference from other 2.4 GHz devices.C. Verify that wireless devices are not using mismatched SSIDs.D. Move the WAP’s antenna to a lower physical location.E.

®3 A and C. Latency can be caused by a variety of factors. In this scenario, interference is the most likely culprit. Checking for interference emitters (such as a microwave oven) is a good place start. You should also check to see if the WAP is set to use the same channel as another WAP (perhaps in a neighboring office or apartment) or a 2.4 GHz cordless phone system.

®̊ B, D, and E are incorrect. B and D are incorrect because incorrect encryption settings and mismatched SSIDs would not result in latency, but would instead result in the client system not being able to connect at all. E is incorrect because moving the WAP to a lower physical location would most likely decrease signal quality and increase latency.

A user has reported that he can’t connect to your organization’s 802.11n wireless network 16. from his newly issued laptop computer. The user works in a location at which you know a good wireless signal is available. In addition, none of his co-workers are having trouble connecting to the wireless network. The user checked the documentation that came with his laptop and verified that it has an integrated wireless adapter and that it is enabled. What should you do? (Choose three.)

Verify that the user is using the correct SSID when connecting.A. Install an 802.11n wireless USB adapter in the laptop. B. Check to see if MAC filtering is in use on the WAP.C.

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Change the channel used by the WAP to eliminate interference from other 2.4 GHz devices.D. Check for surfaces or objects that might be causing the wireless network signal to bounce.E. Verify that the user has configured the wireless adapter to use the correct wireless F. encryption mechanism.

®3 A, C, and F. You should first verify that the user is using the correct SSID when trying to connect to the wireless network. Because this is a newly issued laptop, you should also check to see if MAC address filtering is preventing it from connecting. You should also verify that the user has configured his wireless network interface to use the correct type of encryption for your network.

®̊ B, D, and E are incorrect. B is incorrect because 802.11n WAPs are backward-compatible with 802.11b and 802.11g network interfaces. Installing a new wireless network interface probably isn’t necessary. D and E are incorrect because interference or signal bounce issues would affect all wireless users in the location, not just one user.

Given optimal wireless conditions, which wireless networking standard provides the longest range?17. 802.11aA. 802.11bB. 802.11gC. 802.11nD.

®3 D. All things being equal, the 802.11n standard offers the longest wireless range. Under ideal outdoor conditions, it can extend the wireless signal out to around 800 feet. Under indoor conditions, it has a maximum range of about 200 feet.

®̊ A, B, and C are incorrect. A is incorrect because 802.11a has a maximum outdoor range of about 400 feet with a maximum indoor range of about 120 feet. B and C are incorrect because the 802.11b and 802.11g standards are limited to a maximum outdoor range of about 450 feet and a maximum indoor range of about 125 feet.

Which wireless networking standard is limited to a maximum bitrate of 11 Mbps?18. 802.11aA. 802.11bB. 802.11gC. 802.11nD.

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®3 B. The 802.11b standard is limited to a maximum bitrate of 11 Mbps. Of course, the bitrate drops from the maximum as the distance between the WAP and the network interface increases.

®̊ A, C, and D are incorrect. A and C are incorrect because the maximum bitrate supported by the 802.11a and 802.11g standards is 54 Mbps. D is incorrect because 802.11n supports a maximum practical bitrate of 150 Mbps.

Which wireless security mechanism uses a preshared key (PSK)?19. WEPA. WPA2 EnterpriseB. WPA PersonalC. WAPID.

®3 C. WPA Personal uses a preshared key created from either an 8- to 63-character passphrase or a 64-character hexadecimal passphrase. WPA Personal is commonly used with home networks, but is generally considered inadequate for enterprise networks.

®̊ A, B, and D are incorrect. A is incorrect because, although WEP devices use a common security key, they do not use the type of preshared key used by WPA security. B is incorrect because WPA2 Enterprise uses a RADIUS server for authentication instead of preshared keys. D is incorrect because WAPI uses a central Authentication Service Unit (ASU) instead of preshared keys to authenticate devices to the wireless network.

The Marketing workgroup in your organization decided that they need a stronger wireless signal 20. in their workspace to support the tablet devices they are using to develop a new marking app. To do this, they purchased a WAP and plugged it into an open network jack within an empty cubicle. Which term best describes the security risk in this scenario?

Rogue access pointA. Evil twinB. War drivingC. Data emanationD.

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®3 A. The WAP in this scenario is considered a rogue access point because it wasn’t authorized and isn’t managed by your organization’s IT department. Depending upon how the Marketing employees configured the WAP, it could potentially represent a significant security hole into your network.

®̊ B, C, and D are incorrect. B describes a situation in which a rogue WAP is configured with the same SSID as a legitimate WAP to steal information from unsuspecting wireless clients. C refers to the practice of driving around looking for open wireless networks. D could potentially be a legitimate issue in this scenario, depending upon where the Marketing employees physically located the WAP.

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Wireless Networking - GoCertifycdn.gocertify.com/images/downloads/tracy-network-ch09.pdf · Wireless Networking ... You are implementing an 802.11n wireless network for a small business

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