Scanning with View 4.6 via PCoIP and USB Redirection

[jpaolini]

Hi all,

Hoping I could hear some thoughts on some issues we are having with deployment of scanners being used with View 4.6 PCoIP and USB redirection. I have searched around, and have only found fragments of (sometimes contradicting) information. Essentially, scanning works perfectly but it's unbearably slow. It takes 3-5 seconds to start the scan (which is perfectly acceptable), but it takes 30+ seconds to process each page. The scanner will scan one page, sit and wait for 30 seconds, then get the next page.

A quick overview of our enviornment: users are at a remote site using View 4.6 via a site-to-site VPN backed by two T1 lines (for about 3mbit in total bandwidth). Internet traffic goes out a seperate line; only traffic destined for the datacenter goes out those two T1s. Only the users who need USB redirection are using View with PCoIP (4-5 users), others use RDP. We are using Fujitsu FI-6130 scanners with the latest drivers installed on the clients (which are running View 4.6 on either XP, Vista, or 7; we have tested all three) and the View pool consists of Win7 VMs with plenty of resource allocation.

The scanners are configured to scan at a relatively low 100x100 or 150x150dpi, black and white, to minimize file size. The size of the captured image is either business card sized or letter paper.

What can be done to increase performance? A few seconds between pages would be tolerable, but minutes to scan 5 pages is not. The scanners are critical to the business, but they only scan ID cards and occasionally up to 10 page documents.

I would greatly appriciate any and all thoughts!

[mittim12]

Welcome to the forums.  While I don't have any  thing that can resolve your issue I can tell you that we saw some of the same delays when using USB redirection with scanners across our WAN.  

[admin]

You have to keep in mind, when using USB redirection you are essentially extending the USB connection across a network. In this case you are doing it across a T1, shared you only have 1.5Mbps of bandwidth. That is equal to USB 1.x specs, but the connection is still shared so you do not have nearly that much bandwidth most likely .

If you can imigine streaching a USB cable from your datacenter to your remote sites that is essentially what you are doing.

With latency shared bandwidth etc. several minutes between pages really is not that surprising.

WP

[Lagislav]

We have this exact same issue in our environment, its due to the connection speed at the remote site. We have the same setup in the LAN as well and scanning speed is slower than what you would have in a regular physical connection, but doesn't slow down enough to cause issue in the LAN. Only in the WAN do we see the slowness, we have tried to fix the issue with no resolve, we also have a problem with scanning when it comes to drivers on the Virtual machine and the need to do a re-install the first time a virtual PC is used.... I don't see a work around until more is done in the way of compression etc.. same reason we cant burn to CD/DVD drives as of yet, a T1 just doesn't have the through put to do it...

[jpaolini]

Thanks for the posts! We do have two T1s (for a total of 3mbit) dedicated to the WAN to the remote site. These lines handle only WAN traffic; all other traffic (like Internet usage) goes out a seperate connection. Since the images being scanned are so small, we assumed 3mbit of bandwidth would have supported 4 users scanning at various intervals.

Perhaps USB redirection is better optimized in View 5? We will be testing that as a possible solution along with third-party applications (such as RemoteScan).

[admin]

No optimizations in this area. Long term we can look at more compression. But there is not much that can be done for latency - That is where a lot of the delay comes from.

WP