What is a USB Hub?

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  • Written By: R. Kayne
  • Edited By: Niki Foster
  • Last Modified Date: 18 November 2018
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It seems nearly every electronic gadget manufactured today makes use of the ever-handy USB port. Early computers featuring USB normally had only one or two ports located at the back of the case. Newer computers typically feature several built-in ports, and many cases now place two or more of them in front. Even so, additional ports are often needed, and having them conveniently accessible makes all the difference. The USB hub does just that.

A USB hub is a small, light unit with multiple ports for plugging in USB devices. It is commonly connected to a USB port located on the back of a desktop computer using an extension cable. Once the hub is plugged in, the user can set it wherever is convenient, avoiding the hassle of accessing the rear of the system. A hub is also great for laptops with only one or two ports. When linked up correctly, some hubs can support up to 127 devices.


A self-powered USB hub can be used to connect digital cameras, card readers, keyboards, mice, MP3 players, memory sticks and many other handheld USB devices. For more robust components, such as external drives, printers, scanners or fax machines, an AC-powered device is a better choice. Some of the AC-powered hubs come with an adapter, while others have the capability, but require the adapter to be purchased separately. When shopping for a hub, consumers should be sure to get one that will best meet his or her needs.

Another feature to look for what generation of USB the hub can use. Each subsequent generation operates at a speed faster than the previous. USB 1.1 is capable of data transfer speeds up to 12 megabits per second (mbps), while USB 2.0 can transfer data at 480 mbps, 40x faster. Released in 2008, USB 3 has a maximum speed of 625 megabytes per second (MBps).

A USB hub that supports later generations is often backward compatible, supporting earlier devices as well. The hub automatically detects and runs at the fastest rate the device will support. One that supports 3 cannot "push" a slower device to run faster than its design. Conversely, a hub that only supports 1.1 may or may not support a 2.0 device, but if it does, it will slow it down to 12 mbps — the fastest speed the hub supports.

Virtually all USB devices are plug 'n' play, or hot-swappable, but it's wise to be conservative with this feature when using an external hard drive with a USB port. Data could be lost due to software bugs or if the drive is unplugged while busy.

A USB hub is an inexpensive, handy addition to any system, especially useful with laptops that normally have too few native USB ports and older systems that have rear ports. They can be purchased in a four-port model, a seven-port model, or greater, and multiple hubs can be used for scalable growth.


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Post 13

Please help! I don't know anything about USB hubs. I'm looking for a cheap, small and convenient device. I found reviews online, but I liked all the hubs and I can't decide which one to choose. Can I get some advice please? Which device should I buy?

Post 11

5m max for USB protocol. You need extenders or hubs every 5 meters to achieve this.

Post 10

I am trying to update the firmware for Tableau {Model T8]. But the website mentions the following:

"Tableau Firmware Update uses FireWire (IEEE 1394) to communicate with Tableau device, so you need to have a FireWire port or host adapter installed in your system. (You cannot do firmware updates over USB.)"

We do not have a FireWire port on our computers. How can we get the device updated with the firmware? What adapter and cable do we need to do so?

Post 9

Can I use a USB Hub to connect two PC's to one printer? Ronnie.

Post 8

I'm looking for a mini-usb connector on one side and a 6 pin IEEE 1394 connector on the other. Is there such a cable or can I use an adapter. I'm going from a digital camcorder (mini-USB) to an 1394 box that captures video. I previously used the 1394 box to capture analog video and would now like to use it for the digital camcorder.

Post 7

for laptops there are fire wire adapters that go in the expansion slots/ pc type 2 card slot.

I have the older, larger slot with a fire wire card that cost $30 something. There are now the newer smaller express slot cards that have firewire adapters on them also.

There also are express card slots off a usb line to plug into a usb hub on the laptop for laptops with no card slot.

for desktops you can get a firewire slot/card that goes in the back expansion area for fairly cheap.

Post 6

@ed1369: Did you check your audio settings in Control Panel so that the 'output' or 'sound playback' is coming from your computer's speakers and not the phones only?

@ghunter: It is possible that your USB ports are either A: not installed correctly, or B: you have out of date/none at all USB drivers.

Other than that, I have no idea. Good luck everyone.

Post 5

Try something a little shorter. the top of the spec ops 5m and you could probably double that with success. 70m is simply not going to work well or at all.

Post 4

I recently purchased a "Magic Jack" phone system. It works fine except it knocks out the sound from the PC. Will Plugging into a powered USB port as help?

Post 3

Hello...please help !!!I am not computer smart *at all*. I have been using my digital camera for a year now with no problem, last night I plugged it in and it said power surge on hub port and would not work...I did what it said to do to reset...but that did not help!!! Can you *please* tell me what to do to reset the hub ports (whatever that is) I guess it is where it is plugged in?? I did try plugging it into a different port...did not help.

Thank You


Post 2

how many addresses line do usb hubs use? does data transfer rate depend on the bus speed of system?

Post 1

does anyone ever try to extend a usb cable to 70 meters??? i've tried and still not succeeded yet.

(the device is not recognized by windows)

can someone help me out?

what should i do?

what do i missed?

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