USB 2.0 hub — what the standard means
The USB2534-1080AEN-TR: The USB 2.0 standard (Hi-Speed, 480 Mbps) governs the hub controller's signalling. Each of the four downstream ports negotiates the highest common speed with the attached device — 480 Mbps, 12 Mbps (Full Speed), or 1.5 Mbps (Low Speed). The controller handles the transaction translation (TT) for mixed-speed devices on the same hub, so a Full-Speed keyboard and a Hi-Speed flash drive can share the upstream link without one blocking the other.