Notes:

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• This is the Universal Serial Bus section (USB)
• USB, like PCI (next section), is currently defined for the PC
  - targeted to be a plug-and-play serial cable for lower-bandwidth PC peripherals like the mouse, keyboard, etc.. This would reduce the number of cables and ports on the back of the PC.
• 2 speed definitions: “low” at 1.5 mbits/sec, and “full” at 12 Mbps. Likely need faster speeds (e.g. FireWire, optical) for mass storage devices.
• USB architecture defines a “host” (the PC) and “devices” or “functions” (e.g. the keyboard) with “hubs” in the middle as necessary for fanout.
• But, just as PCI is/may become a more generalized, standard parallel bus, USB may become a more general serial bus.
  - although there are issues. It is specified to run only 15 meters now. And while the speed is above today’s parallel and serial ports, but not fast enough for higher bandwidth devices.- there are a lot of email/web postings about industrial USB - with many issues to be resolved. Like ruggedized connectors.- (note- the point of this foil is to get the audience thinking - not to claim that USB is ready for generalized use).
• As the dates show, USB is relatively recent.