Bufferbloat
Bufferbloat is the latency caused when a router's send buffer fills up — a fast line can suddenly feel like a dial-up connection during any upload.
3 min readReviewed Jul 2026TTML Editorial
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Definition
In depth
Cheap ISP routers ship with oversized buffers to keep bulk downloads fast. Under load, packets queue behind that backlog and wait tens or hundreds of milliseconds before they leave the house.
Bufferbloat is why your ping doubles during a cloud backup, video call or console update. The fix is Smart Queue Management (SQM/CAKE) or a router that supports it.
Deep dives
Guides that use Bufferbloat
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