VMware may rule the server virtualization market today, but its VMware View 4 virtual desktop software falls short when compared with Citrix Systems' XenDesktop 4 in terms of flexibility, capabilities and delivery, according to many experts.
Here, desktop virtualization consultants and users provide clarity on some of the major claims that Citrix Systems and VMware have made about their offerings and explain which gives IT pros the most value.
Flexibility for IT shops
At this point, some say that XenDesktop 4 is better option for big IT shops because it provides many different flavors of desktop virtualization, and it can run on any hypervisor, among other things.
Citrix recently released its Flexcast technology to let IT deliver any type of virtual desktop that end users need -- not just the server- hosted version of virtual desktop infrastructure (VDI) that VMware offers, said Jim Sanzone, a practice director for desktop and application virtualization at New York-based virtualization consulting firm Virtera.
"Citrix has recognized that there is no one silver bullet with desktop virtualization; you won't solve all of your problems with just VDI," said Sanzone, who offers both XenDesktop and VMware View. "There are elements -- app streaming, presentation server, provisioning server - that don't fit into a hosted desktop solution. So people like XenDesktop's flexibility."
Chris Wolf, a Burton Group virtualization analyst and consultant, concurred. "VMware needs to offer similar functionality to Citrix FlexCast, with the View broker able to connect users to a virtual desktop or XenApp/RDS session based on policy."
Also, while XenDesktop runs on any hypervisor, VMware View 4.0 supports only VMware's own vSphere and Virtual Infrastructure 3.5. VMware representatives claim that since more than 90% of the virtualization market runs VMware, this isn't a problem. But enterprises may feel differently.
"VMware's solution turns people off because of the lock-in factor," Sanzone said. "Some organizations are OK with it, but others are interested in Hyper-V and, down the road, may want to use that. If they use VMware View, they can't. That was a complaint from a very large customer recently."
Wolf said he believes that VMware will support VMware View on other hypervisors when the market grows and people ask for it. But VMware has not indicated interest in this.
Since the end-user experience is critical to selling desktop virtualization to users, both companies improved their delivery protocols in the most recent versions.
VMware View 4 will offer a better end-user experience than before, thanks to integration with Teradici's PC-over-IP protocol (PCoIP); a remote display protocol that creates the best-case performance for any network condition.
Prior to this, VMware was using Microsoft's Remote Desktop Protocol (RDP), which was designed for Terminal Services, Sanzone said.
"Before, whenever a big company came to us with certain latency requirements, we knew View wouldn't be able to handle that, but with PCoIP, [VMware] is on the table," Sanzone said. "The expectation out in the field is that PCoIP will level the playing field against Citrix."
Citrix also improved its protocol performance with HDX, which is built on Citrix's well-regarded Independent Computing Architecture (ICA).
While there aren't yet any nonpartisan, published comparisons of PCoIP vs. HDX, the people interviewed for this article said Citrix's HDX outperforms PCoIP on the wide area network.
"For simple, high-speed LAN desktops, in many cases you can't really make a wrong choice because both perform well enough," said Shannon Snowden, a consulting partner at Louisville, Ky.-based IT consultancy New Age Technologies Inc. "However, when the requirements include remote sites with more graphic-intensive applications, XenDesktop is hard to beat."
Landon Winburn, a Citrix systems administrator at the University of Texas Medical Branch, agreed. Winburn uses VMware ESX on servers but chose Citrix's XenDesktop 2 over VMware View 3 last year, in large part because Citrix's ICA protocol was better for large deployments. He said that's still true.
"Citrix has a tried and true protocol that works great on the WAN, where Teradici's stuff just doesn't work as well," Winburn said. "It's fine over a LAN, but that's for smaller shops."
Delivering personal settings
Another part of the end-user experience is personalization -- being able to deliver desktops with all of an end user's settings, images and desktop applications so the desktop looks and acts like a traditional PC.
Citrix includes personalization tools, or user profile management software, within XenDesktop 4 via sepagoPROFILE, but VMware does not include personalization software -- yet. Instead, VMware has an OEM agreement with RTO Software for VMware View 4 today and plans to include it in a future version.
That said, Citrix's personalization software is basic compared with available third-party offerings, and so many companies buy third-party software. Winburn, for instance, uses AppSense's personalization technology with XenDesktop.
Desktop virtualization has a bad reputation for complexity, not just because it still requires IT shops to stitch together various software packages to get everything they want, but also because installation requires communication and cooperation among various IT departments.
"I have seen very high interest but very low adoption of desktop virtualization, and I attribute that to the technology being so across the board in terms of the disciplines required to put it all together," Sanzone said. "The desktop, server, and application guys all have to come together and agree on something to make it happen."
Although one could assume that VMware shops would lean toward VMware desktops, that isn't necessarily the case. "So far, in the deployments we have done, Citrix has dominated the desktops -- even though those customers use VMware in the data center," Sanzone said.
That said, deploying XenDesktop in a VMware shop might take a longer than VMware View -- a point VMware emphasizes.
Patrick Harr, VMware' s vice president of desktop marketing, said, "Citrix takes three times longer to install and integrate into an existing environment, and it requires up to six different management consoles compared to one easy-to-implement virtual desktop solution with one single management console with VMware View."
But deployment times are subjective. "The difficulty in deployment argument is a relative thing," said New Age Technologies' Snowden. "For those familiar with XenDesktop, it's no more difficult to deploy than View."
Sanzone said XenDesktop may take a longer to deploy, "but that is because there are not as many features in VMware View."
Pricing and TCO
VMware View 4.0, which will be available on Nov. 19, comes in two versions. VMware View 4 Enterprise Edition includes the Enterprise Edition of VMware vSphere 4 for free (for desktop use), together with VMware View Manager 4 for $150 per concurrent connection. The Premier Edition also includes VMware vSphere 4 for desktops and VMware View Manager 4, VMware ThinApp 4 and VMware View Composer for $250 per concurrent connection.
Citrix changed its licensing with XenDesktop 4 by integrating a full version of XenApp 5 into the product and moving from "per concurrent user" to "per named user" licensing. As a result, end users can connect to their desktops from any device. Whether that change is good or bad depends on the company and how they use the technology.
The two editions of XenDesktop 4 that include XenApp are Enterprise and Platinum. Enterprise Edition costs $225 per user and includes secure remote access and application streaming. Platinum Edition costs $350 per user and includes secure remote access, application streaming and virtualization, Citrix Password Manager, virtual desktop performance monitoring, WAN Quality of Service, and remote user support.
XenDesktop also comes with XenServer, but the majority of XenDesktop users run it on VMware hypervisors, and they have to pay for ESX or vSphere separately. But vSphere's memory-overcommit capability offers greater virtual machine (VM) density, so it makes a lot of sense to run XenDesktop on that hypervisor, Wolf said.
Both vendors make big claims surrounding total cost of ownership, but these numbers should not be taken at face value. For instance, Citrix claims that XenDesktop reduces desktop TCO by up to 40% and saves up to 90% in storage costs. VMware claims that View reduces desktop TCO by up to 60%, but that percentage is based on an IDC white paper paid for by VMware.
Burton Group's Wolf said some of the big TCO savings numbers vendors tout are "laughable," though desktop virtualization certainly does lower desktop management costs.
To get the most value out of either desktop virtualization offering, Wolf said he recommends buying packages that include application virtualization at a minimum.
Even though Citrix offers more today, the desktop virtualization space continues to evolve. Both Citrix and VMware plan to introduce client hypervisors by mid-2010, and VMware is experimenting with offline VDI capabilities. Citrix plans to release a self-service desktop application portal, Dazzle, by the end of this year that could reduce the number of IT help desk calls, Wolf said.
In the meantime, enterprises should base their decisions on their individual needs -- not on biased vendor claims.
"There's not a concrete answer as far as which is better; it all depends on the requirements. I find value in both offerings," Snowden said. "So the best choice is really going to come down to the project requirements, complete with a detailed discovery of the desktop use profile, to determine which one is the best fit."
Let us know what you think about this story; email Bridget Botelho, News Writer.