USB 2 Hub

  • Thread starter Thread starter Paul
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Paul

If I connect 4 devices to an external USB 2.0 hub, will they all work at
480Mbps or will they only work at a quarter of that speed?
 
Each device will work at 480 Mbps, but only one device can work at this speed at one time.
 
Paul said:
So do the others revert to USB 1.1 speed?
Click to expand...

You were correct the first time the band width is spread across the number
of devices working at the same time, so if all 4 were working together then
they would all share 25% of the band width.




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Paul said:
So do the others revert to USB 1.1 speed?
Click to expand...
No, they will stay connected to the hub as a USB 2.0 connection its simply
that in the case of 4 USB 2.0 devices connected and all attempting to run at
full speed at the same time, the single USB 2.0 feed to the hub would be a
bottleneck so you wouldn't be able to get 480 Mb/sec to each device. What
devices are you wanting to connect and why do you have speed related
concerns? Is connecting some of the devices directly into other USB 2.0 High
Speed ports on the machine not an option?

Paul
 
What
devices are you wanting to connect and why do you have speed related
concerns? Is connecting some of the devices directly into other USB 2.0
High Speed ports on the machine not an option?
Click to expand...
Thanks for the quick responses. Basically I have 5 USB2 devices (HDD, DVDR,
wireless mouse, mobile phone docking device and webcam), the two which I am
concerned speed may impact are an external hard disk and an external DVDR.
The reason for me wanting to use a USB2 hub is so when I need to take the
laptop out, I simply need to remove 1 plug, and it will look a lot tidier.
Additionally I only have 2 USB2 ports on the laptop. Do you think speed
will be an issue with any of the deviced
 
If one device is working at a time, even though they are all on a hub, the
single working device will still work at full speed. If more than one starts
to work, the time will be shared in sequence, as per whatever device is
first ready to send or receive its data as ready. With a hub, the devices
will be scanned and their data sent out the single output as sequentially
shared.

If for example, if you put a mouse and a scanner to share on hub, you will
see
the mouse hesitate when moved while the scanner was receiving or sending
information. Moving the mouse, will also cause data delays to and from the
scanner. They will in fact react on each other's performance. Whatever data
is flowing, it
will still be at the flow rate of the USB port specifications, there will
only be delays from the sharing. .
 
Paul said:
What
Thanks for the quick responses. Basically I have 5 USB2 devices (HDD,
DVDR, wireless mouse, mobile phone docking device and webcam), the two
which I am concerned speed may impact are an external hard disk and an
external DVDR. The reason for me wanting to use a USB2 hub is so when I
need to take the laptop out, I simply need to remove 1 plug, and it will
look a lot tidier. Additionally I only have 2 USB2 ports on the laptop.
Do you think speed will be an issue with any of the deviced
Click to expand...
Possibly there would be speed issues with the first 2 devices and the last
one because these are the most bandwidth intensive. I suggest that you just
plug in those devices separately when needed. If you want to burn a DVD from
the external HDDs contents then plugging one device into one port on the
laptop and the other device into the other port may help. Sometimes separate
ports on a PC share USB bandwidth though so you may have issues under this
case - try your first burn with an erasable DVD just in case or copy the
files temporarily to the laptops own HDD.

Paul
 
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