SBC and Terminal Server still important in the future, even as client hypervisors and VDI take off

I was having a conversation last week with some folks about the evolution of VDI and how the New Desktop will evolve to run anywhere, including locally and offline. Someone asked a question which was essentially "If your June 2010 VDI vision becomes real, then is terminal server or server-based computing (SBC) dead?

I was having a conversation last week with some folks about the evolution of VDI and how the New Desktop will evolve to run anywhere, including locally and offline. Someone asked a question which was essentially "If your June 2010 VDI vision becomes real, then is terminal server or server-based computing (SBC) dead?" It's a great question, and the short answer is "No. Both TS and server-based computing will be important in the future, even in a world full of VDI and client hypervisors."

The future of Terminal Server in a VDI world

If you believe that VDI will truly become as easy to manage as TS (with single disk image management, etc.), and if you believe the user density will of server-hosted VDI will get pretty close the user density of TS (measured hardware in cost per user), then I think it's pretty safe to assume that just about all hosted desktops will move to VDI instead of Terminal Services. After all, if cost and management was not an issue, then why wouldn't you use VDI for all desktops? In this case, a TS desktop might even be more expensive because that would be a completely different kind of technology you had to support. You would have the choice of all users running a client OS (just some local and some hosted), or local users running a client OS and hosted users running a server OS. Which would you rather choose?

This means people wouldn't use Terminal Services for remote hosted full desktops. It does not mean Terminal Services is dead, as people would still use it as the underlying OS feature to serve remote seamless SBC applications. (In other words, all desktops, even remote ones, would be some form of VDI, but many remote apps might still be on Terminal Services.)

The future of server-based computing in a VDI world

I've talked a lot about the fact that VDI and Terminal Server are both server-based computing. (link to video about this) So when I talk about the future of "SBC", I'm talking about remote computing / SBC in a single user (VDI) and multi-user (TS) context. Today's SBC has four main advantages:

  • Management (all users are in the datacenter)
  • Access (use Windows apps from non-Windows devices and from outside the firewall without installing or streaming them)
  • Performance (client-server apps work great, since the remote application client is in the datacetner with a fast connection to the application server)
  • Security ("eyes only" security, with no real data ever leaving the datacenter)

These are the same four advantages of SBC that Citrix has been touting for over ten years.

In the future, the evolution of VDI into the New Desktop will remove the "management" advantage of SBC (in that we will get management for all computing scenarios, even offline / local clients). But the other three--access, performance, and security--will still be advantages of SBC, even in the future.

So even in a world where all desktops are virtualized and managed from a master image and streamed to local hypervisors... even in a world where applications are packaged and virtualized and streamed on-demand to local users... there will still be scenarios where you need to use a fat app over a slow connection, or regulatory compliance issues where no datasets can leave the firewall, and for those cases, good old server-based computing (be it a multi-user or single user back end) will be your friend.

Even though I can't wait for the evolution of VDI and the New Desktop, I say "Long live TS! Long live SBC!"

Join the conversation


Send me notifications when other members comment.

Please create a username to comment.

Should VDI and SBC be really that different for Desktops. I know lot's of people including myself who present Desktops using both. SBC offers the most cost effecetive way to do it, while VDI offers more session isolation. Merge the mangement and you have the best of both worlds, and the advantage of published apps as well!


That sounds like Quest vWorkspace to me. An awesome concept that Citrix needs to grasp.

Consolidation of management technologies is ultra sexy.


If management and density will be comparable then just add seamless app support from client-type OSes (already here no?), use VDI for desktops AND your application farm, gain all the isolation benefits and get rid of TS altogether! Am I missing something??

The thing is, do you believe density will ever match? Logically an OS overhead for each instance seems too much.  However in our world where everything is possible (software being software) I won't be surprised if it will. Or maybe hardware will be so strong it just won't matter.


I think as hardware get's stronger it just makes the SBC case even more compelling for TCO, and it become a concentration risk decision. However wth reliable load balancing much of that goes away.


@appdetective - By SBC you mean just TS or the field in general (TS+VDI)?


@Ron Kuper

TS+VDI to deliver Desktop use cases. I think better hardware helpd with density for classic Citrix and per VM VDI. I am just saying tha classic Citrix becomes even more cost effective with better hardware, so the hardware is not the gating factor, it's more about your risk tolerance and use cases. Hence I agree with Brian and SBC will be around for a long time, and I see no reason either for it not to take advantage of the management improvements as well.


And what if VDI advancements will cause user density to be parallel with TS?


Even if VDI's user density becomes parallel with TS they will play hand in hand because of the technologies they market. VDI = Desktop, TS = Apps.

With user density aside, even if VDI encompases Apps in the future it would most likely include a compatibility engine with TS because of the 80 million users already existing on the proven TS technology.

There has to be more benifits than user density to kill TS and XenApp.


@Icelus 100% agree with you.

@Ron Kuper also don't discount the storage costs of how the vendors are postioning VDI. By definition SBC (mutiple user sessions on a single OS instance) vs. VDI, (Single session on an OS), SBC will always provide grater density irrespective of the strorage type. Vendors who enable session isolation on SBC (think Virtuozzo) also have a way to provide massive horizontal scaling on the cheap with a lot of session isolation.


This is probably true, but in the end TS based deployment is significantly more efficient, specifically users/apps per hardware "box". While VDI has the warm and fuzzy feeling of having "My Own Machine" there is a still a real penalty cost in hardware resources, it will be a while before that gap narrows significantly


I agree with Brian that SBC will be around, but I fail to understand that why everyone  wants to move to  VDI, when till date we don't even know how much and how far it can go.

I feel lot of push for VDI comes from the fact that not every application can be virtualized, there are tons and tons of badly coded application and it's nightmare to get them to work in Citrix, so what' the alternative.. Give user his own desktop and he will be fine.

But for VDI to actually work and prove cost effective the Application virtualization needs to work, developer need to think what is there target audience for which they are writing these apps, where will they be using it.

So if application virtualization works, then I can see people moving back to SBC as it's far more cost effective that VDI.

So it would be interesting in the next year as hopefully Vmware will have their Own protocol rather than Using RDP, with MS releasing RDP 7 and if at all Citrix pulls something really fantastic with the ICA, which further helps reduce the overall cost then I can still see SBC riding high that VDI.

User cases and the Cost is what will drive the future of both technologies.