USB Hubs

Too many devices, not enough plugs.

USB Hubs

Many new computers come with 6 or 8 USB 2.0 ports on them. This may be enough or maybe not. Let's look at some of the common devices people have plugged in to USB:

  • mouse

  • keyboard

  • scanner

  • printer

  • digital camera

  • webcam

  • game controller (a joystick, for example)

  • PDA

  • flash storage devices

These are just some of the most common ones to leave plugged in. There are plenty of toys for kids and grownups that attach over USB. Here are some others that are always plugged in at the super secret headquarters of Late Night PC:

  • UPS

  • Leap Frog mindstation

  • multiformat memory card reader

It looks like you need more USB ports. Fortunately, there's an easy way to get them. It's another piece of hardware called a USB hub. It's important to note before you run out shopping that if you ask for or search for just a "hub," many places will refer you to networking equipment for a totally different device with a similar name.

While we're getting specific, let's look at the different kinds of USB hub that are out there.

Powered

Some USB devices require power from the USB port and others have their own power supply. Usually, a large device such as a printer has its own power supply (an AC wall plug, that is) but smaller devices like mice get their power from the USB port. A device powered by the port has to be plugged in to a port that can supply power. A device that does not require power from the port can be plugged in to any port. If you find this confusing, as I do, then just be sure to buy a powered hub. The way to tell is that a powered hub has to have a plug that goes to the wall. By the way, the ports on your PC are powered.

Low Speed, High Speed, and Full Speed

Different devices have different needs when it comes to communication. A mouse, for example, transmits many small messages very quickly. These messages tell Windows where to put the mouse pointer and when you click. The consequences of messages being late or missed would show up immediately - the mouse pointer would jump around on the screen. A printer on the other hand, needs a lot of data, but if it doesn't get there quickly things will still work - just more slowly. A webcam has both of the demands: lots of data that has to be on-time.

Devices like the mouse use thc low-speed rate. The other two would use high speed or full speed. Only USB 2.0 supports full speed, so a device like the webcam might benefit from a USB 2.0 connection if it is available.

Special and not-so special features

Some hubs have features that are not related to USB. I have a hub built in to my Hercules external sound card. I've also seen them built in to flash card readers, printers, monitors and keyboards. These are nice to have but don't pay extra for them if you're not certain they meet your needs.

Most USB hubs give four ports. Once you consider that you need somewhere to plug it in, you only gain three ports. The next best thing to more ports is a stackable hub, I suppose. Several hubs have this feature, where two hubs can be mounted one atop the other in order to save space.

While any USB 2.0 hub will work with USB 1.1 devices, I've found one from Belkin that supports both but makes special arrangements for USB 1.1 devices. Each USB 1.1 device plugged in to the hub gets access to a full 12 megabits of bandwidth. It's as if each device got its own USB 1.1 bus. This means that those USB 1.1 devices won't slow each other down.

USB 1.0, USB 1.1, USB 2.0

Most computers sold today have USB 2.0 support. Many of the USB devices and hubs out there today are still USB 1.1. There's no problem with getting a USB 1.1 device, as long as you realize that the device can't communicate as fast as a USB 2.0 device. A USB 1.1 hub, on the other hand, could cause headaches when you realise how long it can take to copy the pictures off youre camera. Look for the USB logo that includes the words "hi speed"USB Hi Speed Logo. This logo indicates that the device or hub is capable of the faster rates of USB 2.0.

At least one USB hub is becoming essential on all but the most basic PC configurations. Don't buy one before you need it, but don't just grab the first one you find when you do need it. Consider the ideas I've talked about here and get what works best for you. As always, if you have any questions, don't hesitate to contact us and we'll help you sort things out.