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The USB 1.1 standard specifies that a standard cable can have a maximum length of 5 meters with devices operating at Full Speed (12 Mbit/s), and a maximum length of 3 meters with devices operating at Low Speed (1.5 Mbit/s)."
Is that really true? Why would the cable length be lower for a slower-speed connection? --Mortense (talk) 22:49, 11 January 2016 (UTC)
According to the source, it's 5 meters for USB 2.0 devices, and 3 meters for USB 1.1 devices. Basically devices with more power can use longer cables. That makes a lot more sense. Sakkura (talk) 08:47, 12 March 2016 (UTC)
I didn't bother to look this up, but my recollection is that a "Low Speed" device is allowed to have a cheaper cable. Originally, this was "safe" because all cheap cables had to be permanently attached to their devices, so if you bought an interchangeable cable, it was required to be the better, Full Speed capable cable. I think "cheaper" allowed for an unshielded cable, and maybe higher impedance as well. (Of course, nowadays, buyer beware, when buying USB "compatible" products.) 184.108.40.206 (talk) 20:56, 20 July 2016 (UTC)
The descriptors are essential to implementing USB. The relationship between the device descriptor, configuration descriptors, interface descriptors, endpoint descriptors, the USB#Device_classes, the actual interfaces and endpoints of the USB device, and any other device state is pretty convoluted, and should be documented here. But at the moment there's no mention of descriptors at all. Beyond Logic has done a decent job distilling the USB spec to a readable manual, and chapter 5 could be summarized to explain descriptor transmission and selection. —winggundam 00:34, 27 May 2016 (UTC)
I came to this article hoping it would tell me what a "USB client port" is, but I was disappointed. What is a "USB client port"? How is it different from a "USB host port", a "USB device port", or a "USB OTG port" -- or is it a synonym for one of them? --DavidCary (talk) 17:39, 12 August 2016 (UTC)
@DavidCary: The USB On-The-Go article offered a hint of an answer with "Use of USB OTG allows those devices to switch back and forth between the roles of host and client." There's no source given for that statement. Normally the terms used are "host" and "device". You can have one host on a USB bus and up to 127 devices. USB On-The-Go has a mechanism where if two On-The-Go devices are connected together that one of them will switch itself to being a "host" and then they carry on using the standard host/device protocol.
This does not fix the underlying issue in that some web pages on the Internet use the word "client" though I don't know if it's common enough to merit adding to this article. A tricky aspect is finding a decent source to cite that "client" means "device" when some people talk about USB ports. The phrase "USB client" appears four times on www.usb.org. I looked at how the word "client" was used on all four hits and it was always in the context of "client driver" software but I did not see an explanation of what that is. The phrase "client port" is never used on www.usb.org. Thus while "USB client port" appears about 8,750 times on the Internet it seems to be a non-standard term. --Marc Kupper|talk 00:09, 19 August 2016 (UTC)
The characteristics, cabling, connectors of USB 2, 3 and type C are sufficiently different to have a different page for each of them. The way USB is described now is rather convoluted. Theking2 12:38, 25 September 2016 (UTC) — Preceding unsigned comment added by Theking2 (talk • contribs)