Easy way to solve remote display protocol compatibility issues: Don't use a remote display protocol!

Last week I wrote that one of the main challenges in the leading VDI products on the market today is that their remote display protocols-ICA and RDP-don't work with all applications. I also put forward the idea that until VDI can work for 100% of applications, it won't grow much beyond the niche solution it is today.

Last week I wrote that one of the main challenges in the leading VDI products on the market today is that their remote display protocols—ICA and RDP—don't work with all applications. I also put forward the idea that until VDI can work for 100% of applications, it won't grow much beyond the niche solution it is today. Putting those two thoughts together, one could argue that better protocols = broader VDI adoption.

But the whole "protocol capabilities" discussion is really about graphical application performance and local peripheral compatibility. The ultimate long-term goal of these remote computing protocols is to make them work as well as a normal locally-installed OS.

Taking a step back, it's important to think about why companies will adopt VDI in the first place. Fundamentally it's about saving money. Most of savings will be in the form of reduced management costs.

Since today's VDI solutions are SBC-based, companies also get the traditional SBC-related benefits in addition to cost savings. (These SBC benefits are things like data security, decent app performance over slow connections, back-end live migration of running VMs, access from any client, etc). But of course SBC-based VDI environments suffer from the same downsides of any SBC environment, like poor graphics performance and not being able to work offline.

So how can a company get the cost savings of VDI without the downsides of SBC? Simple... don't use SBC!

In other words, imagine a VDI environment where the desktop VM is running locally on the client device instead of on a backend server in a datacenter. Crazy, eh? "Client-based computing." (CBC?) What a concept! ;)

At VMworld in Cannes earlier this year, VMware previewed a technology they're calling "Offline VDI." (Check out the middle bullet item about half-way down that page.) With offline VDI (OVDI), users can "check out" a desktop VM that they're accessing remotely. The VM is copied down to the client device where it can be booted and executed locally. When the user is back online, they power off their local VM, click an option to check it back in, and their delta disk image changes are sent back up to the server where they can use their VDI image in an online SBC way again.

At this point OVDI is just a basic technology preview, and it's rough around the edges, but it solves some interesting problems for VMware:

  • OVDI fixes the protocol capabilities problem. What protocol is better than ICA, RDP, Spice, or PC-over-IP? VGA!
  • OVDI fixes the peripheral problem, in that all local USB camera, mics, phones, scanners, devices, etc. work as planned.
  • And of course, by definition, OVDI fixes the offline problem.

Will offline VDI replace SBC-based VDI?

With these three major advantages of OVDI, why would anyone use the (now) "old school" SBC-based VDI? Well, OVDI still has some disadvantages when compared to SBC-based VDI, namely:

  • OVDI requires sufficient local computing capabilities that can run the VM.
  • OVDI requires that the VM disk image somehow gets from the server to the client.
  • OVDI requires at least some kind of client device support, since there needs to be a baseline OS/hypervisor/VMM of some sort.

OVDI + SBC-based VDI: The 100% solution?

Going back to that whole "VDI needs to be 100% to be mainstream" thing, do you think that traditional SBC-based VDI (like what we have today), combined with offline VDI for certain use cases, could be the ultimate solution?

This "ultimate" solution, in my mind, is still tied to being able to use a single stateless disk image for all users—online and offline. Imagine if we had a true layered model, with the base OS, the user environment, and applications all running in their own isolated layers in the stack. Then a single disk image could be used for about as close to 100% of users as we'll ever get.

Other vendors besides VMware are thinking about this too. Microsoft's purchase of Kidaro this past January could be the first steps of their entry into the offline VDI space. Citrix doesn't have a local VM story today, but maybe they can piggyback on Microsoft / Kidaro and add some "capabilities" there too?

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One possible approach in the near future could be having such image on what we know as of today as a USB flash drive (like these pen drives we all carry around today with 2GB/4GB). What if such image could be loaded on something like a 256GB stick? And what if the VM player could be intelligent enough to boot a certain snapshot when you are at home and a slightly different one, more secure/locked down when you are at the office?

This way we would carry our 'VDI' image with us. Hardware could be potentially modified to allow such sticks to be booted only under certain physical devices (so if I lose my stick you cannot boot it at your home device).

And when at the office the central server could push whatever changes were required to bring that image up to date. Or even disable it completely. The possibilities with such approach are endless. 

That is definitely something I can see happening and working! I would love to have something like that, that I could plug to a dock at home and have a 'Desktop', plug to a notebook type 'dock' and have a notebook and plug at my work 'desktop dock' and have a work desktop!


The two key components that Offline VDI doesn't do much with is mobility + data.  For mobility I'm referring to the user being frequently disconnected.  Yes offline VDI means I can take a laptop with an offline VDI image on it.  But what amount of data has to be exchanged to allow me to check-out/check-in my image?  Gigabytes perhaps?  That's not exactly WAN/WWAN friendly IMHO.  What about user workspace management?  How does that play in this offline VDI model?  How much user desktop personality data needs to be exchanged in this manner?  And what size (in KB/MB) does it involve?  Finally, Offline VDI speaks nothing to the data exchange components required for most applications used by businesses.  Out of the thousands of applications used by Enterprises, how many of them can be run in an offline capacity (less than 10% I'd bet).  Now since you're stating Offline VDI + SBC, I can see the potential where there's benefit there.  However, why use Offline VDI at all and just call it a laptop from the start?  That's really what it is.



Traditional SBC is still the best solution for 90%+ of all application presentation. It is not old school - it is simply mature and proven technology.

Sure - highly intesive apps with multimedia or high graphic needs apps will not work in a traditional Winframe/XenApp SBC environment. However, you can stream these exception apps to the desktop or stream the OS to the desktop or do what you are promoting and stream the VM to the desktop.

Citrix is completely forgetting her current customer base. I think this is a major blunder on their part. The products they are promoting now have a 6 month to 2 year proof of concept sales cycle. They need to come out with XenApp 5 or they will be losing market share to the likes of Ericom, VMWare and MS.

Citrix! Do not forget your base of customers and your current cash cow! Yes - you have potential products with potential revenue but do not forget your current friends and family.


Obligatory disclaimer: I am a VMware employee.

What you described (carrying a managed VM around on a USB stick) has been shipping from VMware for over a year as a feature of ACE 2.0. The feature is called "Pocket ACE" - if you google for "vmware pocket ace" you'll find info about it from VMware's website and third parties. 

ACE is aimed at enterprise-wide deployments, but we ship a free "ACE option pack" with every copy of Workstation if you just want Pocket ACE for personal use.

Relevant to Brian's article: Offline VDI uses ACE as the client hypervisor for running the local VM.


Oh I am fully aware of ACE. What I meant (sorry for not describing it more detailed) is something similar to ACE but:
- Requires no local OS. The hypervisor is either implemented at the hardware level (on the 'docks') or is on the portable device (in this case the USB stick) itself. So no matter where I connect my stick, my OS loads.
- Everything I do on my VM is replicated (intelligent replication) once I connect back to my corporate infrastructure.
- The image that boots, is different (based on snapshots) depending on the dock I connect the stick to (i.e. my notebook-like dock that would travel with me, my desktop-like dock at home, my desktop-like dock at the office, etc).

I guess the key feature is being able to run this on machines (as you saw I named them 'docks') with no OS at all.

Maybe Provisioning Server?

Also, check these guys out ( www.panologic.com ).  Just met them last night.  They don't use RDP or ICA to connect to their broker from their "different" thin device to VMware VDI.


What do they use?  The web site is not entirely clear aout how this stuff works!!  How is the keyboard/mouse/display data transferred between Pano box and back end virtualisation platform?

Completely hate companies that make it a challenge to see how their product works, if they wanna make me sweat to find information on their product  they can go suck.


I did not get an answer, other than "it isn't RDP or ICA".

One neat thing they have is the ability to support client side USB to the VM, because they don't use RDP or Port-ICA.


Programmable logic gates.



I agree with you on the fact that the technology to get this synchronized in a cool matter not requiring Gigabit LAN is a bit of a challenge..

But another thing i see, are we not looking at the fact of moving data outsite the datacenter again, half the customers i talk to about VDI loves the fact that their data can finally stay inside the datacenter, with offline VDI are we not moving back to decentralized deployments .... with new cool sync-toys :-)

I think i will still stay to my argument that an online-solution is the best way for many/most companys. The time where you are truly offline, outside cell-phone coverage etc, isnt that time turning into less and less, along with the bandwith of mobile connections growing faster and faster and ever more reliable? dont know how it is in the rest of the world but in Denmark we are doing 7mbit on 3G mobile cards for about 50$ a month flatrate.



I meant PLA (Programmable Logic Arrays)


Can't agree more - if they can't make it straight-forward to understand how it works from a technical level then why should we waste time trying to get the details?

show me a futur... With a combinaison of technology...

in the past Application were executed locally
(user - application)  

there were SBC with central application hosting
user <-----virtulization-------------- application executed centrally
    limitation : central execution, no offline...

there is now application virtualization and streaming
user - (application) <------ streamed ------- application
    allow offline access and local power consumption

Citrix (but others could/would/should) add capabilities that give us a choice (in a single simple solution) to have the choice :
       - (application) <---- streamed -------
user                                                      application (datacenter)
       <---------------------virtualized -------

We now have the choice to get the same application executed the side we want...
Citrix called that Application Delivery... whatever.

Have the same look at OS.

in the past, there were locally installed OS
(desktop - OS)

there is Desktop Virtualization with central OS hosting
desktop <-----virtualized--------------- OS executed centrally
    limitation : central execution, no offline...

there is also (from several vendor) OS streaming (Provisioning Server) (or local virtualization like ACE)
desktop - (OS) <------ streamed -------
    allow offline access and local power consumption

Why not in a near futur get a Desktop Delivery simple single solution that give you the choice where you wanted you OS to be executed ?
           - (OS) <------ streamed ----
desktop                                        OS (datacenter)
           <-----------virtualized -------

Nice view ?


Check out this technical whitepaper that reveals what these guys do (to some extent):


It looks like the Pano device is a glorified USB hub that connects all the peripherals to a VDI instance over a LAN connection - sort of like USB over IP. They include a management GUI and they appear to provide a broker that front ends the VMWare infrastructure for managing the VDI pool, much like Provision does.


I am with Sean on this one. One of our 'great ideas' people can back with this idea from the VMWare coference in Cannes las Feb. The problem is most of our users live on the other end of a WAN connection.

Couldn't agree more. 

Not to mention that XenApp releases (especially x64) are increasingly buggy.  4.5 has a host of faults (some 'enhanced' security features) that need fixing.

Wish they would put more emphasis on supporting their existing product than pushing something I don't need right now. 

Pano Logic is a new small startup so I think we can give them a break while they figure out how to build an efficient communication vehicle.  The marketing guy was pretty clear when face to face with a group of potential customers, but they might just choose not to reveal their IP (not that you could sniff a lan to see what they are doing).  Yes, the device is based around a programmable logic gate array, rather than a CPU.  It is remoting not only usb, but also the video content.  Basically, their approach is to put as few moving parts and logic out at the client as is necessary, and do the work at the broker.  So for example, it seems that if a new USB device needs a driver it would be handled at the broker.

Yes definitely, Here is what I would like to see, a bootable USB stick (XPe, WinPE, WINFLP, or linux even) that had Wireless built in,  with a VM player of some sort on it that runs up the Virtual disk image right from the USB stick. Yeah it would have to be a 10 gb or more in size stick but it is then a computer in your hand/pocket.  It is doable. Hell MS could sell it as Virtual OS on a Stick amd make a killing.  You could use this thing on any thin client or device or even a RedFly type of device.    

Oh and the data CAN stay at the data center then. You can certainly keep the user folders on the server and keep the local OS locked and clean.

Check out this Video with one of the cofounders.  Now my interest is picqued.



What does it matter what they use? If the solution works as advertised, they don't have to necessarily disclose their intellectual property to you. Not that you'd be able to understand it anyways.

Even more annoying when you watch the demo and see how seemingly awesome the technology is but have no further details to sate your appetite!!!

Must admit, I look forward to hearing more, but at the end of the day some kind of protocol must be in use between device and viretual infrastructure and as Brian points out, it's the protocol that is usually the weak point in a connected model VDI solution.

I was indirectly associated with this (isr.cmu.edu) about 5 years ago.  Seems like the industry is just beginning to catch up with the technology research...

Anyone know pano device cost? Seems to be abit vmware vdi centric. I assuming they are opening up to other VDI solutions.

I heard $300 / device.  They give the broker away for free. 

Disclaimer : I work for Teradici.

Before you place PC-over-IP in the same protocol category as ICA, RDP, Spice, I suggest you take it for a test-drive. And I challenge you to find a software program or USB device that does not operate the same as if it were on a full blown desktop computer under your desk.

Further I don't understand this technology.  I thought one of the 'main' reasons a CIO would decide on virtualization for their company for desktop virtualization (VDI) would be for 'security'.  You now have removed all of those security features by taking and storing your desktop as a file format on a separate PC.  In addition, you gain little or no cost savings on the client device.  Now you have 2 PC's to manage :the server in the datacenter, and the desktop device.  How is this saving capital costs and IT operation costs?

I understand how this feature is useful for special cases, but I don't see it as a replacement to fix the VDI problem.



If you look at the whole history of computing.. it goes in cycless..



add dumb terminals (terminals are now 100% dependent on the connection)

move to mini computers

develop desktop pc's (computers are now independent of everthing else)

build arpnet, link pc's together

develop internet

build server farms

move computing back to servers

thin out workstations (computers are now 100% dependent on the connection)

move to offline model  (computers can operate independent of everthing else)

and the patterns repeats..

once we get microwave or wimax technology where devices are "always connected" (iPhone3 or 4)

then computing will move back to the core where it is cheaper and easier, and the devices become disposible.


Just my observations,

Bradford Knowlton



Here is my question. I am a small part time IT guy. I have maybe a total of 15 machines with servers. I want to somehow deploy a image of an os with software loaded on it and maintain the image which streams out to the rest of the workstations. Also, I want to get away from buying desktops and thinclients. I would rather place my money in a server which can handle all the users. What would i need to use! lol.

I did get a change to talk with panologic with there pano, and they are sending me one to test.

I have tried to install citrix xendesktop, but I have had no luck getting it to install.

Vmware, I have tried and I like it, but I want to be able to do a either a xero client or a PXE boot.

 By the way, with these remote / protocols. Which would be ideal for a user interface of a local desktop with the way the graphics are? We do have a few people who use autocad for rendering and lol FPS games.


Thanks for your thoughts.


First time poster here so go easy on me =)

I think for the foreseeable future we're going to be relying on multiple technologies to deliver a user experience that our clients are used to. I know in my position a combination of SBC/TS and App streaming/virtualization is going to get me as close to the seamless on demand desktop as I'd like while trying to save a buck. I love the idea of OVDI for the added power but I'm not sure how practical it is for me, at least with the current trend it's moving in.

One consideration that I haven't seen mentioned but I have in the back of my mind is the new trend of ISP's capping bandwidth for home users. I know there's nothing set in stone and they're still throwing around the idea but if we're going to talk about streaming more and more content to our roaming users I'm curious at what point, if there is a point, that we hit a brick wall. I keep seeing comments about with the current Internet infrastructure we're going to hit a usage wall in a few years and I'm curious as to how it all plays out.



I'm sure some others on here could help you better than I could but if you're looking for a one to many streaming image solution on agnostic hardware you'll probably want to look at Citrix's Provisioning Server [Ardence.] It really boils down to how much you can spend and how flexible you need to be for your users as to whether you're better off with SBC or VDI.

There are several products out/coming out with protocols that are able to offer more graphic intensive needs including: PC-over-IP, RDP+, Spice, etc. It's really just a matter of searching and researching to get an idea of where to begin.