CWDP-305 Exam Dumps - CWNP CWDP Wi-Fi Design Questions and Answers

Signal-to-Noise Ratio (SNR) is a critical metric in VoWLAN deployments, as voice applications are sensitive to latency and require clear signal quality. SNR is calculated by subtracting the noise floor from the received signal strength indicator (RSSI).

Given:

Required SNR: 25 dB

Noise floor: -88 dBm

To achieve the required SNR:

RSSI = Noise Floor + SNR

RSSI = -88 dBm + 25 dB = -63 dBm

The CWDP-305 Official Study and Reference Guide emphasizes the importance of maintaining adequate SNR for voice applications:

"Voice over WLAN requires a minimum SNR to ensure call quality and reliability. Designing for appropriate RSSI levels relative to the noise floor is essential."

Therefore, to meet the system's requirements, the minimum RSSI should be -63 dBm.

Comprehensive and Detailed Explanation:

Virtual Private Networks (VPNs) are commonly employed in WLANs for:

Remote AP tunneling to a corporate WLAN controller or VPN concentrator:This allows remote access points (APs) to securely connect back to the corporate network over the internet, ensuring that data traffic is encrypted and secure.

Client device connectivity to corporate resources from unsecured public networks:VPNs enable client devices to securely access corporate resources when connected to public or unsecured networks, protecting sensitive data from potential threats.

For accurate deployment of access points in a multi-floor indoor environment, providing a camera and marking tools is essential. A camera allows the installation team to reference visual cues from the design, ensuring APs are placed in the correct locations. Marking tools help in identifying precise mounting points on ceilings or walls, facilitating adherence to the design plan. These tools, combined with the design documentation, enable the installation team to execute the deployment accurately, maintaining the integrity of the WLAN design.

Starting with a Tx Power Level of "1" at 17 dBm, each increment halves the power:

Level 2: 17 dBm - 3 dB = 14 dBm

Level 3: 14 dBm - 3 dB = 11 dBm

Level 4: 11 dBm - 3 dB = 8 dBm

Converting 8 dBm to mW:

10^(8/10) ≈ 6.31 mW

The closest provided option is 6.25 mW.

In WLAN design software, defining different “requirement areas” allows the designer to assign distinct RF and performance requirements to different parts of the floor plan. For instance, a voice-critical conference room may require –67 dBm minimum signal strength and a specific SNR, whereas a storage area might only require basic coverage.

From CWDP-305:

“Requirement areas allow WLAN designers to set different RF performance targets such as minimum signal strength, SNR, and data rate for specific parts of the deployment area. This enables tailored design strategies.”

— Reference: CWDP-305 Official Study and Reference Guide, Chapter on Wireless Design Process

Comprehensive and Detailed Explanation:

The current WLAN setup with only two APs supporting over 300 client devices is insufficient and leads to performance degradation. Simply adding more APs without a proper design can cause co-channel interference and other issues. Upgrading Ethernet connections or increasing AP power does not address the core problem of inadequate design for high-density environments. The appropriate action is to redesign the WLAN specifically for the auditorium, considering factors such as client density, application requirements, and RF environment to ensure reliable and efficient Wi-Fi performance.

When working at heights, especially during the installation of Access Points (APs) on high ceilings, safety is paramount.Personal Protective Equipment (PPE) such as hardhats protect against head injuries, high visibility vests ensure that workers are easily seen, and body belts (or harnesses) provide fall protection.These are standard safety measures in such environments.NWExam

The CWDP-305 Official Study and Reference Guide underscores the importance of appropriate PPE:

"Ensure that installation personnel use appropriate PPE, including hardhats, high visibility vests, and body belts, when working at heights."

Receive sensitivity indicates the minimum signal strength at which a device can successfully receive and demodulate a signal at a specified data rate.In this case, a receive sensitivity of −82 dBm @ 18 Mbps means that the device requires a signal stronger than −82 dBm to reliably demodulate data at 18 Mbps.Therefore, the device must receive a signal with a strength greater than −82 dBm (i.e., closer to 0 dBm) to maintain that data rate.

In large enterprise WLAN deployments, efficient IP address and VLAN assignment is crucial for scalability and performance. Common and recommended methods include:

Static VLAN Assignment per SSID:Each SSID is mapped to a specific VLAN, allowing for straightforward traffic segregation.

Dynamic VLAN Assignment via AAA:Utilizing RADIUS servers to assign VLANs based on user credentials or group memberships provides flexibility and centralized control.

VLAN Pooling:Assigning IP addresses from multiple VLANs in a round-robin fashion helps distribute clients evenly and prevents DHCP exhaustion.

However, assigning VLANs based on real-time radio signal metrics like RSSI or SNR is not a standard or recommended practice. Such metrics are variable and can lead to inconsistent VLAN assignments, complicating network management and potentially affecting client performance.

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