WiFi Power Save Latency Analysis | Generated by AI
Here’s the breakdown:
ANALYSIS: .52 and .29 OUTLIERS
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192.168.1.52 — avg 0.6 ms
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ARP flag: "permanent" — this is YOUR AIR (lzw-mac.local)
MAC: b2:e2:c6:39:f3:dd (locally administered = Apple private WiFi address)
Why 0.6ms: pinging yourself = loopback, never leaves the NIC.
Not special — it's just the local machine.
192.168.1.29 — avg 446.7 ms
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MAC: 86:c5:c7:ef:f6:5f (locally administered = randomized/private MAC)
Likely: an Apple device (iPhone/iPad) using private WiFi address
Per-ping breakdown:
icmp_seq=0 324 ms
icmp_seq=1 298 ms
icmp_seq=2 196 ms
icmp_seq=3 1045 ms ← spike!
icmp_seq=4 45 ms
icmp_seq=5 849 ms
icmp_seq=6 701 ms
icmp_seq=7 860 ms
icmp_seq=8 641 ms
icmp_seq=9 693 ms
stddev = 312 ms ← enormous jitter
WHY: This device is in WiFi power-save mode (802.11 PSM).
- Radio sleeps to save battery
- Wakes up periodically to check for buffered frames
- Each ping has to wait for the next wake window
- That's why latency ranges 45ms to 1045ms randomly
- 0% packet loss = it IS reachable, just sleeping between checks
Other slow devices:
.14 (Xiaomi, 86ms) — phone in power-save, less aggressive
.49 (Apple, 97ms) — Apple device, moderate power-save
The pattern: battery-powered devices (phones, tablets) use 802.11 power-save mode. They batch buffered frames and wake on a schedule. The more aggressive the power-save, the higher the ping latency. .29 is the worst offender — likely an iPhone/iPad with aggressive battery optimization. Wired devices (.36, .18) and always-on devices (.1 router) stay low.