CWDP-305 Exam Dumps - Certified Wireless Design Professional

The IEEE 802.11y amendment introduced support for operation in the 3.65–3.7 GHz frequency band, allowing for higher power transmissions up to 20 watts Equivalent Isotropically Radiated Power (EIRP).This enhancement was designed to improve wireless coverage and performance, especially in environments requiring extended range and penetration.

The increased power and frequency range provided by 802.11y facilitate better service in areas where traditional Wi-Fi bands may be congested or less effective.

Defining wall materials (e.g., drywall, brick, concrete) in WLAN design software is essential for accurate RF modeling. Different materials attenuate RF signals to varying degrees, and propagation models account for these losses to calculate realistic signal coverage.

From CWDP-305:

“Accurate modeling of RF signal behavior requires defining wall and obstacle materials to account for signal attenuation and reflections. This improves the accuracy of predictive design tools.”

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

EAP-TLS (Extensible Authentication Protocol-Transport Layer Security) is considered one of the most secure EAP methods. It requires both the client and the server to have certificates, enabling mutual authentication. This method eliminates the need for passwords, reducing the risk of credential theft.

EAP-TTLS allows for server-side certificates and can use passwords for client authentication, making it less secure than EAP-TLS.

PEAP encapsulates EAP within a TLS tunnel, typically using server certificates and password-based client authentication.

In WLANs utilizing 802.1X authentication, client roaming involves re-authentication processes, which can introduce latency. To enhance roaming efficiency, key caching mechanisms are employed:

Pairwise Master Key (PMK) Caching:Allows a client to reuse a previously established PMK with an AP, reducing authentication time during roaming.

Opportunistic Key Caching (OKC):Enables clients to use the same PMK across multiple APs within the same mobility domain, facilitating faster transitions.

Fast BSS Transition (802.11r):Introduces protocols for quick and secure handoffs between APs.

Implementing these key caching protocols significantly improves client roaming performance in MCA networks.

Comprehensive and Detailed Explanation:

IEEE 802.3at, also known as PoE+, provides up to 25.5 watts of power per port. To support 6 access points requiring PoE+ power:

25.5 W/AP × 6 APs = 153 W

Considering some overhead for power loss and future scalability, a minimum PoE budget of 180 W is recommended to ensure reliable operation.

Co-Channel Interference (CCI) occurs when multiple APs on the same channel are heard in the same area, even at relatively low signal levels. CCI is not eliminated simply because signals are below −75 dBm. In fact, CCI is a concern even when APs are heard at levels as low as −85 dBm or lower.

From CWDP-305:

“CCI can be problematic even when the signal from neighboring APs is heard at levels between −85 dBm to −93 dBm. Effective channel planning requires minimizing overlap of same-channel signals at or above these thresholds.”

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

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.

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.