Ever Wondered How Your Device Finds WiFi? The Answer Lies in Beacon Frames!
Ever wondered how your phone instantly finds WiFi networks? It’s all thanks to Beacon Frames—the heartbeat of every WiFi network! 
APs send beacons every 100ms (by default) to announce their presence, helping devices discover and connect efficiently.
What’s Inside a Beacon Frame?
A beacon frame isn’t just about the WiFi name (SSID)—it carries essential network details:
Basic Info:
SSID & BSSID – Network name & AP’s unique identifier.
Timestamp & Beacon Interval – Synchronization & transmission timing.
Channel & Frequency:
Country Code – Regulatory domain & allowed frequencies.
Channel & Bandwidth – Whether the AP operates on 20, 40, 80, or 160 MHz.
Security & Authentication:
RSN (WPA3, WPA2, Open WiFi) – Defines encryption & security policies.
Authentication Type – Pre-shared key (PSK) or enterprise security.
WiFi Capabilities:
HT (WiFi 4), VHT (WiFi 5), HE (WiFi 6), EHT (WiFi 7) – Determines supported
features.
OFDMA, MU-MIMO, TWT, BSS Coloring – Enhances efficiency & performance.
Traffic Management:
Traffic Indication Map (TIM) & DTIM – Helps devices wake up for buffered data.
Vendor-Specific IEs – AP custom features like AP Name broadcasting.
How Beacons Affect WiFi Performance?
Essential for network discovery & fast roaming.
Helps clients select the best AP.
Can cause high overhead in congested networks.
Impacts battery life of mobile & IoT devices.
Optimizations:
Adjust beacon interval to reduce airtime usage.
Limit excessive SSIDs to prevent beacon floods.
Optimize DTIM settings for better power efficiency.
Real-World Beacon Frame Analysis
I’ve attached a wireless sniffer log 
that captures actual beacon frames in action. Open it
with Wireshark and use this filter to analyze them:
Filter: wlan.fc.type_subtype == 0x08
What interesting insights have you discovered from beacon frames?
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