Free Practice Questions for CWNP CWDP-305 Exam

In a centralized data forwarding architecture, Access Points (APs) tunnel all client traffic to the WLAN controller.The controller then processes this traffic and forwards it to the appropriate destination.During this process, the controller maps the Differentiated Services Code Point (DSCP) values from the client's IP packets to the appropriate IEEE 802.1Q priority tag values.This mapping ensures that Quality of Service (QoS) is maintained across the wired network, allowing switches and routers to prioritize traffic based on these tags.Cisco

Microwave ovens operate at frequencies around 2.45 GHz, which can cause interference with Wi-Fi signals in the 2.4 GHz band. During lunch hours, increased use of microwaves in the break room can lead to intermittent Wi-Fi connectivity due to this interference.

The IEEE 802.11-2016 standard specifies two methods for Fast BSS Transition (FT) to facilitate fast and secure roaming:mrn-cciew

Over-the-Air (OTA):The client communicates directly with the target AP to perform the authentication exchange during roaming.

Over-the-Distribution System (Over-the-DS):The client communicates with the current AP, which then communicates with the target AP over the distribution system to perform the authentication exchange.

These methods are designed to reduce the time required for re-authentication during roaming, ensuring minimal disruption to ongoing sessions.

The CWDP-305 Official Study and Reference Guide states:

"802.11r defines two methods for fast BSS transition: Over-the-Air and Over-the-DS, both aimed at reducing latency during client roaming."

To measure performance metrics such as throughput and latency, you must associate with the AP and generate/receive real traffic. This type of survey is called an active survey.

From CWDP-305:

“Active surveys assess the end-user experience by collecting real-time data, such as throughput, latency, and packet loss, which cannot be captured by passive surveys.”

Passive surveys only collect information from beacons and probe responses without associating with the AP.

— Reference: CWDP-305 Official Study and Reference Guide, Chapter on Post-Design ValidationandTroubleshooting

The Effective Isotropic Radiated Power (EIRP) is calculated using the formula:

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The Things Network

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EIRP (dBm) = Transmit Power (dBm) + Antenna Gain (dBi) - Cable Loss (dB)

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blog.iptel.com.au

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Assuming negligible cable loss, we first convert the transmit power from milliwatts to dBm:

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Everything RF

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Transmit Power = 25 mW = 10 * log10(25) ≈ 14 dBm

Now, adding the antenna gain:

EIRP = 14 dBm + 3 dBi = 17 dBm

Therefore, the EIRP of the APs in this design is 17 dBm.

Comprehensive and Detailed Explanation:

In predictive modeling for WLAN design:

B.Setting the AP transmit power to match the average client device capabilities (e.g., 25 mW) ensures a balanced link budget, promoting reliable two-way communication and accurate coverage predictions.

A.While default antenna patterns can be used, they may not accurately represent the actual deployment, especially if different antennas are planned.

C.Channel width settings should reflect the intended deployment plan, which may include 20 MHz, 40 MHz, or 80 MHz channels, depending on the environment and requirements.

D.Using pre-configured vendor-specific AP and antenna models in the predictive software ensures that thesimul-ationclosely matches the actual hardware characteristics, leading to more accurate predictions.

The Received Signal Strength Indicator (RSSI) is a measure of the power present in a received radio signal. While it is commonly used in WLAN location-based services due to its simplicity and the fact that it doesn't require additional hardware, RSSI-based positioning is susceptible to environmental factors like multipath propagation and signal attenuation, leading to lower accuracy.

In contrast:

Angle of Arrival (AoA) determines the direction of the incoming signal, offering better accuracy.

Time of Arrival (ToA) measures the time it takes for a signal to travel from the transmitter to the receiver, providing precise distance measurements.

Time Difference of Arrival (TDoA) calculates the difference in arrival times between multiple receivers, enhancing location accuracy.

To validate fast roaming (802.11r), a protocol analyzer is required to capture authentication frames and reassociation frames between APs. These allow you to verify if fast BSS transitions are occurring and if the endpoint is participating in FT.

From CWDP-305:

“Fast BSS Transition (802.11r) validation requires capturing EAP exchanges and reassociation frames during roaming. A protocol analyzer with multiple adapters can monitor channels simultaneously during transitions.”

— Reference: CWDP-305 Official Study and Reference Guide, Chapter on Post-Design ValidationandTroubleshooting

Comprehensive and Detailed Explanation:

In warehouse environments, physical changes can significantly impact WLAN performance. Over time, the addition or rearrangement of inventory (e.g., pallets, shelving) can alter RF propagation, leading to coverage gaps or interference. Therefore, it's essential to inquire about any inventory changes that may have occurred since the initial installation.

Other Options:

A.DHCP lease exhaustion typically affects IP address assignment but is less likely to cause location-specific WLAN issues.

B.Changes in receive gain are hardware-related and less common unless equipment has been replaced or reconfigured.

D.While rogue APs can cause interference, they usually affect broader areas and are less likely to cause isolated issues unless specifically deployed nearby.

Band steering is a technique used to encourage dual-band clients to connect to the less congested 5 GHz band. However, some client devices are persistent and may not respond to steering attempts, continuing to probe only on the 2.4 GHz band. To ensure these clients can still connect to the network, band steering algorithms are designed to eventually allow association on the 2.4 GHz band after a certain number of ignored Probe Requests. This approach balances optimal network performance with client compatibility.

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