Most of those difficulties are centered around the integration of the various components. For example, a certain version of a connection broker may not support a particular virtualization platform. Some products work only with specific hypervisors. Case in point: VMware View 4.0, which works only with VMware's own platforms. If you're looking to use Hyper-V as a virtualization platform, VMware View 4.0 is not an option.
Another common problem is troubleshooting display protocols and the associated network infrastructure. Display protocols, which encapsulate all I/O between the client device and the virtual machine, can be bandwidth-intensive and influenced by network latency. Tracking down the cause of those issues requires advanced network diagnostic tools and, in some cases, additional products to shape network traffic.
Other complications come in the form of troubleshooting user complaints related to performance and usability. Tools to diagnose such problems and fully support users are only just starting to come onto the market. Recently, I tested management products from SolarWinds and Ipswitch that eliminate many of the management issues; however, these products add significant costs to a VDI deployment.
Many of the VDI products on the market could be improved by incorporating troubleshooting and management capabilities directly into the offering and reducing the need for third-party applications.
One thing is certain: VDI places significant loads on your network infrastructure. If you have limited bandwidth and high-latency connections, problems with performance and reliability are sure to rear their ugly heads.
VDI's costs are coming down, just as better VDI tech appears
Beyond the technical challenges is an often unstated fact: VDI can be expensive, simply because of the high requirements for server and network resources. A November 2008 Forrester Research report estimated each VDI user would cost an organization $1,760 for the cost of the thin client software, server, storage, and licenses for virtualization software, desktop OS, and applications.
However, prices have dropped by about half since then, to $900 per user, says Natalie Lambert, the Forrester analyst who wrote the report (and is now a Citrix employee). As the technology continues to mature and prices decline, VDI should become economically and technologically viable for more and more businesses.
For example, Microsoft is changing its software license to simplify VM provisioning, VMware is set to launch a new version of VMware View, which will natively support offline modes. And Citrix is pushing further into the desktop virtualization space with new client hypervisors. Products such as MokaFive and Wanova have arrived on the market, and they allow administrators to fully manage, secure, update, and sync Type 2 client virtual machines on remote clients. Other companies, such as LeoStreme and Ericomm, are creating connection brokers that are hypervisor-agnostic, allowing administrators to combine various virtualization platforms to deliver VMs using the best technology for the particular need.
These advances have led to startups that offer cloud-based desktop provisioning (with the ungainly acronym DaaS, for "desktop as a service") to small businesses, effectively eliminating the need to purchase software, servers, and the other elements that make up a traditional small-business IT department. That same logic is starting to affect the enterprise culture, where CTOs are now examining the DaaS concept to bring fully managed virtual machines into the enterprise, eliminating much of the support and management concerns associated with traditional desktop PCs. Desktone also offer DaaS as a "private" cloud offering that IT can deploy in its own data center.
Several vendors are looking to provide preconfigured VDI systems. For example, PanoLogic $24,450 Pano Express is a 50-user turnkey VDI system with 50 Pano client devices, a high-performance server, 50 Microsoft Virtual Enterprise Centralized Desktop (VECD) licenses, and VMware vSphere Essentials, for a cost of $489 per client if all 50 seats are used. Citrix and thin client maker Wyse Technology have partnered to deliver a zero client device aimed squarely at delivering VDI as a simple-to-deploy-and-manage concept. Thin client maker NComputing is pursuing a similar path by partnering with VMware.
As such efforts continue, it is only a matter of time before enterprises can broadly embrace VDI technology. The question is when, not whether.
This article, "The unvarnished truth about VDI desktop virtualization," was originally published at InfoWorld.com. Follow the latest developments in virtualization and Windows at InfoWorld.com.
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