CWDP CWDP Outdoor and Mesh Networking

Question 1

What is the primary advantage of using a mesh WLAN architecture over a traditional wired infrastructure deployment in outdoor environments?

Accepted Answer

Elimination of cabling requirements by using wireless backhaul between nodes

Answer

Mesh networks use wireless backhaul between nodes, avoiding the need to trench cables to every AP location.

Question 2

In an outdoor point-to-point wireless bridge, what is the first Fresnel zone and why must it be kept clear?

Accepted Answer

An elliptical region around the direct path where reflections constructively interfere; obstruction causes significant signal loss

Answer

The first Fresnel zone must be at least 60% clear of obstructions to avoid destructive interference that degrades link performance.

Question 3

What path loss model is most commonly used for outdoor WLAN link budget calculations in open terrain?

Accepted Answer

Free-Space Path Loss (Friis) model

Answer

The Friis free-space path loss model is used for outdoor line-of-sight links, calculating loss based on distance and frequency.

Question 4

Which regulatory domain restriction must a CWDP consider when deploying outdoor 5 GHz point-to-point bridges in the US?

Accepted Answer

UNII-2 and UNII-2 Extended channels require DFS radar detection and avoidance

Answer

UNII-2 and UNII-2e channels in the 5 GHz band require Dynamic Frequency Selection (DFS) to detect and avoid radar interference.

Question 5

In a mesh network, what is 'backhaul efficiency' and how does the number of hops affect it?

Accepted Answer

Each additional mesh hop typically halves available client throughput due to half-duplex relay overhead

Answer

Each wireless mesh hop roughly halves throughput because the relay node must receive and retransmit on the same channel.

Certified Wireless Design Professional (CWDP) Practice Test