NEW QUESTION 1
You are attempting to determine timing information within a packet capture of a WLAN protocol analyzer.
What time is used to display the time the packet was captured based on the system clock in the computer?

• A. Relative
• B. Arrival
• C. Interframe
• D. Delta

Answer: B

Explanation:
Arrival Time—This is the time that is assigned to a packet after it is processed by the host system. This timestamp is dependent upon the system clock of the computer, and designates when the packet was captured.

NEW QUESTION 2
Several users have reported WLAN network connection issues and the users connect to the same AP. These users are spread throughout a 320 square meter area. Using a spectrum analyzer, you see RF energy across the entire 2.4 GHz band at significant signal strength levels. The users all connect using either HT or ERP devices.
What is the likely cause of this problem within this area?

• A. Wide-band jammer
• B. Microwave oven
• C. Bluetooth devices
• D. Video camera

Answer: A

NEW QUESTION 3
To what data rates can a 5 GHz PHY device shift when changers occur in the signal strength?

• A. 11, 5.5, 2, 1
• B. 24, 18, 12, 5.5
• C. 24, 18, 11, 2
• D. 24, 18, 12, 6

Answer: D

NEW QUESTION 4
You are concerned about attackers gaining access to your WLAN from outside the facility.
Why does reducing the output power on the APs not provide sufficient certainty that an attacker outside the facility cannot gain access?

• A. Because RF signals can be received even when weak if using a Mac OS X computer
• B. Because the attacker can simply use high gain antennas
• C. Because the attacker can increase the output power of the radio on the client
• D. Because the attacker will simplify use a lower gain antenna and a radio with higher receive sensitivity

Answer: B

NEW QUESTION 5
You have captured 802.11 traffic using an adapter that includes the radio tap header. You see several frames often called announcement frames in the capture.
What best describes these types of frames?

• A. They only include beacon and probe request frames
• B. They are used to allow a STA to awake from sleep and for no other reason
• C. They only include beacon and probe response frames
• D. They are meant to provide information to the network that may result in state changes, but they are not open for rejection

Answer: C

NEW QUESTION 6
The To DS bit is set to 0 and the From DS is set to 1. What best describes this 802.11 frame?

• A. A frame being transmitted from an AP to a client STA
• B. A frame being transmitted in a mesh BSS
• C. A frame being transmitted from a client STA to an AP
• D. A frame being transmitted directly from one client STA to another

Answer: A

NEW QUESTION 7
When evaluating modulation and coding schemes, you must determine the best coding rate available. In 802.11 MCS tables, what is the best coding rate from the perspective of highest data rates?

• A. 5/6
• B. 3/4
• C. 2/3
• D. 1/2

Answer: A

NEW QUESTION 8
You are analyzing a problem with a specific client adapter. The vendor specifications sheet does not provide detailed information.
What tool can you use to provide the most detailed specification information in many such cases?

• A. WLAN controller
• B. Spectrum analyzer
• C. FCC ID Search
• D. Wi-Fi finder

Answer: C

NEW QUESTION 9
Given: Adjacent Channel Interference (ACI) can cause frame corruption and poor performance in WLANs. You are using a protocol analyzer in the attempt to detect ACI.
What should you look for in such a scenario?

• A. Look at Retry counts
• B. Capture on the channel you think may be impacted by ACI and see if any frames are captured from adjacent channels
• C. Look for frames with a low signal strength value in the radio tap header
• D. Look at CRC errors

Answer: B

NEW QUESTION 10
What is the formula used to calculate the Duration field value in an RTS frame?

• A. RTS Duration field = CTS duration
• B. RTS Duration field = Data or management to be sent frame duration
• C. RTS Duration field = Data or management frame to be sent duration + CTS duration + one ACK duration + three SIFS
• D. RTS Duration field = Data or management frame to be sent duration + CTS duration

Answer: C

NEW QUESTION 11
You are evaluating a protocol capture file in Wireshark. The following filter is applied: wlan_radio.11ac.bandwidth - - 4
What kind of frames are displayed?

• A. Only 40 MHz frames
• B. Only 80 MHz frames
• C. Only frames supporting 4 spatial streams
• D. Only frames supporting 4 radio chains

Answer: B

NEW QUESTION 12
You have implemented an AP at a remote office. It is a single-band AP supporting 802.11ac. Several users complain that their laptops cannot connect to the WLAN. These laptops are from multiple vendors and range in age from 2 to 4 years. The SSID and security profile settings are correct. All default settings were used on the AP with the exception of the SSID and security settings.
What is the most likely issue preventing these STAs from connecting to the AP?

• A. They do not support VHI and only support OFDM
• B. They are 5 GHz-only devices
• C. They are 2.4 GHz-only devices
• D. They do not support the basic data rates

Answer: B

NEW QUESTION 13
You are troubleshooting problems with DHCP in relation to lightweight APs. They vendor class identifier (VCI) is not specified in the DHCP server. When you contact vendor support, they inform you that it is not necessary.
When is this information true?

• A. When only one client option 43 value is required
• B. When only one AP exists on the subnet
• C. When the DHCP server is directly connected to the subnet
• D. When only one client option 60 value is required

Answer: A

Explanation:
The DHCP server should be configured to provide the IP address information to the APs, but it may also be required to pass information for option 43. Option 43 is a vendor information option and can be used for any vendor purpose. The vendor class identifier (VCI) (for example, “Cisco AP c3600”) is used with option 60 to determine the appropriate information to return with option 43.

NEW QUESTION 14
The data rate for a data frame is 150 Mbps in 5 GHz. What rate is used to transmit the PHY header information?

• A. 1 Mbps
• B. 150 Mbps
• C. 75 Mbps
• D. 6 Mbps

Answer: A

NEW QUESTION 15
You are working in an organization that has implemented an SCA-based WLAN. You want to change the RF channel for a single AP.
What can you do to perform this task with some SCA solutions?

• A. Access the AP using SSH and change the channel
• B. Access the AP through the console port and change the channel
• C. Access the AP using Telnet and change the channel
• D. Convert the network to MCA

Answer: D

NEW QUESTION 16
What action is taken automatically by 802.11 APs and client STAs as the signal strength of the link weakens in order to improve the quality of the RF communications overall?

• A. Output power is increased
• B. RSSI is increased
• C. Data rates are reduced
• D. Antenna gain is increased

Answer: C

NEW QUESTION 17
When using a commercial WLAN protocol analyzer, you notice that it is listing vendor names for some APs and client STAs.
What is the source of this information?

• A. Broadcast name resolution
• B. Banner grabbing
• C. DNS name resolution
• D. Vendor OUI values

Answer: D

NEW QUESTION 18
While troubleshooting DHCP issues, you perform a protocol capture in order to determine if the DNCP pool is depleted. The capture does not show DHCPnak messages.
Where else could you look to determine if the pool is depleted?

• A. Switch logs
• B. DHCP server logs
• C. Spectrum analyzer
• D. AP logs

Answer: B

Explanation:
A very common problem for WLANs is DHCP pool depletion. This occurs because many wireless clients come-and-go from the network quickly. If a client connects for only two or three minutes and the lease duration is set to multiple days (3-8 days is not uncommon), the IP address will be lost for that entire time. To resolve such issues, create more pools and reduce the lease duration to hours instead of days. Look for DHCP negative acknowledgement or server log errors to determine if the IP pool is depleted.

NEW QUESTION 19
As the WLAN administrator in your organization you are responsible for troubleshooting connection issues. Several STAs are connecting to the network, but are unable to communicate after connection. You suspect a DHCP problem. After capturing traffic on the wired-side of the AP, you want to view only DHCP traffic.
What filter in Wireshark can be used for this purpose?

• A. DHCPv6
• B. DHCP
• C. BOOTP
• D. DHCPv4

Answer: C

NEW QUESTION 20
During an initial install of a controller-based WLAN, the APs are not locating the WLAN controller. The controller is two router hops away from the nearest AP. DHCP is not used. When performing a packet trace, you see a DNS response code of 3 targeted at one of the APs.
What is the problem?

• A. The DNS server is not authoritative for the domain
• B. The router is not forwarding packets to the DNS server
• C. The controller host record has not been created in the DNS server
• D. The authentication to the DNS server failed

Answer: C

NEW QUESTION 21
You are considering disabling the data rates of 1, 2, 5.5 and 11 in the 2.4 GHz band. What advantage might this provide to the networks operating in this band?

• A. The antennas will be able to zero in on the higher data rates better
• B. The range of the PHY preamble and header will be reduced
• C. Frames that must be transmitted at the lowest common data rate can be transmitted at higher data rates after the change
• D. The RF signals will not travel as far

Answer: C

NEW QUESTION 22
HOTSPOT
A manager at a retail outlet has complained that an incident occurred allowing a STA to launch an attack against another STA connected to their public Wi-Fi hotspot. He has asked you to troubleshoot the situation and verify that all possible measured are being taken to prevent this.
What configuration should you check in the AP?
[MISSING]

• A. Mastered
• B. Not Mastered

Answer: A

NEW QUESTION 23
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