The problem in one sentence
Bufferbloat is excessive latency caused by oversized network buffers filling up when your connection is saturated. When a big upload or download uses all your bandwidth, packets queue up and wait, and your ping can jump from 20 ms to hundreds of milliseconds.
How to spot it
Run a speed test that measures latency under load, not just when idle. NetPulse Pro monitors your ping during the download and upload phases and reports the increase. A small increase (under 30 ms) is healthy; a jump of 100 ms or more means you have bufferbloat.
Why it matters
- Video calls freeze and audio drops when anyone else uses the connection
- Online games spike in lag during downloads or cloud backups
- Web pages feel sluggish even though your speed test looks great
- Multiple users on one connection interfere with each other constantly
How to fix bufferbloat
- 1Enable Smart Queue Management (SQM) — usually fq_codel or CAKE — on your router.
- 2Use a router with SQM support (OpenWrt, and many modern consumer routers, include it).
- 3Set the SQM bandwidth limits slightly below your measured line speed so the router, not the ISP, controls the queue.
- 4Enable QoS to prioritise latency-sensitive traffic if SQM isn't available.
- 5Replace an old modem/router that can't keep up with your line speed.
The counter-intuitive fix
SQM deliberately caps your throughput a little (often 5–10%) to keep the queue short. You trade a tiny bit of peak speed for dramatically lower latency under load — almost always worth it.