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Many have asked us how USB 2.0 or Hi-Speed USB mode specifically can handle today's ever-changing applications, particularly in the multimedia field. The original USB has an inherent problem to meet the bandwidth requirement of then current CD burners and hard drives. If memory serves us well, USB CD burners hit the bottleneck at 8x or 1.2MByte/s, and USB hard drives couldn't exceed a pitifully 1MByte/s.
When USB 2.0 introduced Hi-Speed USB mode, it boosted bandwidth to 480Mbit/s or 60Mbyte/s. The forty-fold jump from the original USB's 12Mbit/s has paved way for a number of improved devices. As we've seen, there is a dual SDTV tuner, each of the tuners consumes 8Mbit/s after the MPEG-2 conversion. For DVB-T/B USB tuners, each HDTV stream requires 55Mbit/s or 11% of what USB 2.0 offers. Technically, Certified Wireless USB can handle several HDTV channels simultaneously. For a few USB Video Class-enabled camcorders available, DV mandates 3.6Mbyte/s (or 43Mbit/s) for the linear video stream; it fills up a hard drive at a rate of 13GB per hour.
As for a lot of USB storage, burning a DVD-R at its fastest rate or 16x takes up 21MByte/s or 169Mbit/s. That translates to 35% of overall USB 2.0 speed. Hard drives, however, demand huge amount of bandwidth that USB 2.0 cannot meet; we've heard a USB 2.0 hard drive has sustained 36 to 40MBbyte/s in the absolute best scenario. USB flash drives have also reached 33MByte/s, but there seems to be some limitations in the NAND itself so you shouldn't expect their speeds to skyrocket in a next year or two. For most consumers, there shouldn't be a problem with running out of bandwidth.
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