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USB Solutions >> USB over Network >> Simultaneous sharing?
(Message started by: cof on Jan 20th, 2006, 12:19pm)

Title: Simultaneous sharing?
Post by cof on Jan 20th, 2006, 12:19pm
Is it not possible to simultaneously share a USB device between two clients? The site seemed to say that it was, but I find that I can only connect one client at a time which means getting on the phone and asking the other user to disconnect so I can connect.

Is what I'm trying to do possible? If so, how?

Even if we can't, what would make this work for us is to be able to use a command line to automatically connect/disconnect. Is there some interface or plans to build one in so that when we execute the program it automatically connects and disconnects when completed?

Title: Re: Simultaneous sharing?
Post by Andrew on Jan 24th, 2006, 3:11am
Yes, unfortunately, it's not possible to share one USB device between several clients at the same time.

We have plans to develop some sort of switching feature in the next versions of our "USB over Network" product so we would be greatly appreciated if you have some ideas about possible realization of such switching feature (how could that work in general, what command line keys could you need and so on).

Title: Re: Simultaneous sharing?
Post by cof on Jan 31st, 2006, 7:54am
I guess that ideally it would work invisibly. You divide the time slices up so that each computer thinks that it has unfettered access. The other way and certainly easier to implement would simply be that when a computer makes a request to the USB device it tries to take ownership. Other computer(s) give up ownership automatically unless the device is in use at that instant.


Title: Re: Simultaneous sharing?
Post by terry.mann on Jul 10th, 2006, 7:40am
cof is absolutely right. This software is merely a 'remote access' package as opposed to 'sharing'.
I uninstalled it within 5 minutes as it doesn't do what is claimed.
In my opinion, no user intervention should be required. The 'shared' device should be accessed only when required by the client and then immediately released.

However, I am extremely interested in Andrew's comments about future versions.
Andrew, would you mind letting me know when you plan on releasing such a version please?

Title: Re: Simultaneous sharing?
Post by Andrew on Jul 11th, 2006, 7:08am
Unfourtunately there is no solution right now. Even in theory there is no known method to determine when user wants to access USB device (because Windows nothing knows about the device if device is not connected to computer). Also there is no method to determine when the device should be disconnected (e.g some devices generate USB traffic even when they are in the idle state). So...

Even our "switching feature" of the future program version will work for some USB devices only (e.g. USB dongles)

Title: Re: Simultaneous sharing?
Post by chaoskeeper on Aug 21st, 2006, 3:12am
sorry to bring up this thread again, but after downloading the software I would be very interested in a "simultanous" mode too.

so here my 2 cents:

a) once the USB is switched to one person, the program could just simulate like it would still be connected.
This could be done by a "scan device" function that checks what exactly the device does when it's in idle mode (takes like 30mins to be sure)

b) there are programs that monitor the traffic between your pc and the usb device. so when you combine them properly a "switch to device when needed" shouldn't be a problem

c) I guess that Windows tries several times before giving up the connection to an active USB port, so even if you don't get the access right away it should work with a small delay.

I guess that's enough for today :)

keep up the good work

Title: Re: Simultaneous sharing?
Post by DynamoBen on Jul 3rd, 2008, 11:42am
Is the "switching feature" available in the latest release? If so how does one enable/access it.

Title: Re: Simultaneous sharing?
Post by Andrew on Jul 4th, 2008, 1:01am
Hi guys,
That feature is not implemented even in the latest version.
We have some new ideas on that, but still no working solution.
Thanks for your interest.

Title: Re: Simultaneous sharing?
Post by DynamoBen on Jul 9th, 2008, 12:51pm
I would be using it for dongle sharing. Dongles are checked every 30 minutes.

If you get to the point where you would like some field testing done please let me know.  ;)

Title: Re: Simultaneous sharing?
Post by favoir on Sep 10th, 2008, 6:31am
In our company only two persons work with USB-over-Network.
We share one Dongle for our compiler.
My colleague very often forget to disconnect.
Possible solutions could be:
1.Connect/disconnect via command line.
2.Adjustable timeout (e.g. 30 seconds) if no traffic.
Is it possible to get a version with one of the two solutions?

Title: Re: Simultaneous sharing?
Post by TheCPUWizard on Oct 6th, 2008, 7:28am
Please, please please...do NOT chage (the default at least) to allow multiple clients to the same USB device.

The ramifications would be staggering.

I believe that the current method [Device exists only on one machine, Logical Resource may be shared at the OS level if appropriate] is the correct way.

Title: Re: Simultaneous sharing?
Post by Keith on Oct 22nd, 2008, 2:50am
USB over Network 3.5 released. From now on it's possible to connect shared USB device even if it's occupied by a remote user
(as a result the remote user becomes disconnected).

In other words one Client Component can forcibly disconnect another Client Component and grab shared device.

This feature may be enabled/disabled by means of Server Component interface.

http://fabulatech.com/img/uploads/usbnet-access.png