USB 3.0 interfaces are known to generate RF interference in the 2.4 GHz band due to the high-frequency noise emitted by the differential signaling in USB 3.0 cables and ports. This interference can reduce SNR, especially for devices located close to the USB port.
From CWDP-305:
"USB 3.0 cables and ports can emit broadband noise in the 2.4 GHz band, negatively impacting receive sensitivity and SNR. This can distort measurements during protocol analysis or performance testing."
- Reference: CWDP-305 Official Study and Reference Guide, Chapter on ProtocolandSpectrum Analysis

A specification sheet (spec sheet) provides detailed technical capabilities of a device, including supported Wi- Fi standards (e.g., 802.11a/b/g/n/ac/ax), number of spatial streams, band support, and security protocols. This helps WLAN designers understand performance expectations and compatibility.
From CWDP-305:
"Specification sheets are critical for evaluating client capabilities. They include information about supported frequency bands, maximum data rates, MIMO capabilities, and supported security protocols."
- Reference: CWDP-305 Official Study and Reference Guide, Chapter on Wireless Design Process

Orthogonal Frequency Division Multiple Access (OFDMA), introduced in 802.11ax, enhances efficiency by dividing a channel into smaller sub-channels called Resource Units (RUs). This allows multiple devices to transmit simultaneously within the same channel bandwidth, reducing latency and improving throughput.
Unlike previous standards like 802.11n and 802.11ac, which primarily support single-user transmissions per channel, OFDMA's ability to handle multiple concurrent transmissions without relying on MU-MIMO leads to more efficient spectrum utilization and better performance in dense environments.
Reference: CWDP-305 Official Study and Reference Guide, Chapter on Designing for Specific Applications

In WLAN deployments, each SSID is typically mapped to a unique VLAN. This allows logical separation of traffic, enabling different security policies, QoS settings, and routing for different user groups or services.
From CWDP-305:
"Each SSID in a WLAN is usually mapped to a different VLAN on the wired infrastructure. This allows for segregation of traffic, application of different network policies, and enhanced security enforcement."
- Reference: CWDP-305 Official Study and Reference Guide, Chapter on Infrastructure Design

During a successful client roam between APs (when connected), the client typically sends a Reassociation Request to the new AP, and the AP responds with a Reassociation Response. This sequence helps maintain the client session, including IP addressing and encryption state.
From CWDP-305:
"Roaming involves a Reassociation Request from the client and a Reassociation Response from the new AP.
These frames are critical markers of a successful handoff in active WLANs."
- Reference: CWDP-305 Official Study and Reference Guide, Chapter on Post-Design ValidationandTroubleshooting