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Is VMware’s Horizon FLEX the answer to BYOD?

By Mark Lockwood | October 14, 2014 | 0 Comments

At VMworld 2014 in Barcelona today, VMware announced Horizon FLEX, which is essentially a marriage of multiple existing VMware technologies that, together, provide an interesting client-hosted virtual desktop option.  FLEX utilizes Fusion, Player, Mirage, and some technology from AirWatch to allow fully-managed virtual desktops to exist on Mac, Windows, and Linux PCs.

Why would VMware, with all of this momentum in the VDI market, head down the rabbit trail of client-hosted virtual desktops?  To understand that, let’s think like a VMware customer about some of today’s EUC issues.

1.  “We love our VDI deployment, but we are finding more and more off-line use cases.”

For quite a while, both VMware and Citrix tried to solve the off-line use case within the standard framework of VDI by streaming desktops or transferring bits in the background to allow a virtual desktop to live in two places at once.  Both companies had limited success, and it must be said that the Citrix method was superior to the VMware method.  Citrix continued to improve and refine their offering so that today, it is the very solid XenClient product, while VMware allowed View offline mode to atrophy.  What Horizon FLEX offers is a virtual desktop where the authoritative source of the virtual desktop lives on the end point, meaning that the end point is the expected execution point of the virtual desktop.  VMware has had very good technology for running virtual machines on end points for years, and by adding the management and control of Mirage to the mix, an organization can deliver a fully-enabled, fully-controlled virtual desktop to a user that will allow that user to work seamlessly offline.

2. “We want to allow users to bring in Macs and their own PCs, but we don’t want to have to support our applications executing on dozens of different types of end points, browsers, and operating systems.”

Of course, there is already a very good answer for this in Server-Based Computing (Citrix XenApp, Microsoft RemoteApp), but as detailed in “Selecting the Right Application Delivery Model for Virtual Desktops“, there are a few limitations.  Therefore, presenting a full, corporate desktop OS image is, in some cases, a better option.  This can be, and often is, achieved with server-based VDI, but enterprise IT quickly discovers that the savings of not providing a laptop to each user is nullified by having to purchase servers and storage in the datacenter in order to run virtual desktops.  Allowing those desktops to utilize the CPU, memory, and disk of the end point can greatly reduce the infrastructure cost of a BYOD project.  Additionally, the BYOD user gains the benefit of #1 above; he or she can work in an off-line situation just like someone with a corporate laptop.


Am I telling you that Horizon FLEX will be a nirvana for IT?  I am not.  This technology has existed for years outside of VMware, with companies like MokaFive and products like Citrix XenClient.  In fact, VMware was first in this game, back in 2006, with a product called VMware ACE, that was far ahead of its time and was terminated in 2011.  Problems still exist in this model that prevent it from being a panacea, such as:

–  Performance will be dramatically variable depending on the end point.  If someone brings in a 2007-era Windows Vista laptop that has 140 processes running in the background, the desktop you give them to run on that machine is not going to run well.  But do not be mistaken — IT will get the lion’s share of the blame.  And imagine the new kinds of “slow VDI” calls your help desk will get to answer!

–  Security issues of BYOD do not go away.  If someone brings their own laptop that has four keyloggers and two rootkits and plugs it into your network, Horizon FLEX will not save you.


Ultimately, I’m happy to see VMware utilize the technology they already have in-house to deliver a new option to organizations looking to enable BYOD, off-line use of virtual desktops, or both.  Options are good, and I believe that the time is right — perhaps overdue — for VMware to offer a robust solution for client-hosted virtual desktops.

Will you consider running Horizon FLEX?  Do you already run virtual desktops on end points?  Tell us how in the comments.


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