While server virtualization has largely settled down into a slugfest between VMware (vSphere), Microsoft (Hyper-V) and to a lesser extent Citrix (XenServer), and Red Hat (KVM), the desktop virtualization field remains wide open, and is being targeted by numerous startups with highly creative and appealing solutions. While VMware (View and ThinApp), Microsoft (App-V and MED-V), and Citrix (XenDesktop) certainly represent the large players in the field, startups like Install Free, MokaFive, Virtual Computer, SlickAccess, Unidesk, Kaviza, and Ringcube all bring unique and differentiated solutions to the table.
VDI consists of running the user’s OS (and all of their applications, and all of their customizations) on an instance of a user OS (XP, Vista, or soon Windows 7) on a server, and providing remote access from the user to that instance of the OS via a connection broker running RDP, ICA, or VMware’s PC-over-IP solution licensed from Teradici. The notion of VDI has been extended by a set of announcements focused upon desktop resident hypervisors from first Citrix with “Project Independence” and then VMware. Both Citrix and VMWare have also talked about the idea of a management solution that would allow users to seamlessly switch between a hosted VDI solution and an offline desktop hypervisor with synchronization.
Recently a flurry of innovation in the space has occurred, driven mostly by venture funded startups who believe that for a variety of reasons that this is not an elephant war – at least not yet. There are three basic approaches taken by the vendors below:
- Products that consist of client side hypervisors with back end packaging and management tools.
- Products that create packages of either applications or entire desktops that run on an existing desktop or laptop OS
- Products that improve upon “server-centric” VDI in some respect, but that basically adhere to the centralized execution architecture of VDI
Client Side Hypervisors with Back End Management
Formerly called Citrix Project Independence, Citrix XenClient is a desktop resident hypervisor that supports multiple guest OS images. One image is designed to be the “corporate image” which will be managed by IT and which will be backed up and kept consistent with the corporate master image. The other images are the user’s own desktop operating system(s) which the user can customize with their own settings or installed applications.
VMware Client Virtualization Platform
VMware CVP is a bare-metal client hypervisor optimized to run on desktop and notebook client PCs utilizing Intel® Core®2 and Centrino® 2 processors with Intel® vPro™ technology. CVP will extend the centralized management capabilities of VMware View by enabling end users to run their virtualized desktop environments on desktop or notebook PCs and work online or offline while IT administrators manage these environments securely from a central location. This helps customers further reduce the operating costs of PC management while boosting business flexibility and end user productivity.
Virtual Computer NxTop is the combination of a bare metal client side hypervisor with a back end management system, the NxTop Center that manages master images, users, applications and policies for all of the deployed client hypervisors.
The Neocleus platform leverages the open source Xen hypervisor to run natively on a user’s desktop or laptop removing the constraints of running virtual machines (VMs) on top of a host operating system. VMs are spawned directly from the hypervisor and run as isolated environments completely un-tethered from the native host client operating system. This method provides enhanced system performance eliminating the inherent drain on resources that switching between a host and guest environment produces. To improve performance further, the platform integrates Neocleus’ pioneering device model approach featuring full device pass-through to allow the user to maintain direct access to the underlying device hardware.
Application or OS Packaging with Back End Management
Symantec End-Point Virtualization Suite
Symantec has assembled a very interesting combination of two virtualization approaches into its End-Point Virtualization Suite. Symantec Workplace Streaming solution is able to dynamically stream applications to users at lauch time in a manner similar to what Microsoft does with App-V. The Symantec Workspace Virtualization product is an application virtualization solution that puts end user applications into containers that are isolated from the underlying desktop OS. Both of these products are combined with Symatec Workspace Profiles (a licensed version of RTO Virtual Profiles) onto the Symantec End-Point Virtualization Suite.
InstallFree is neither a VDI based OS centralization solution, nor a client side hypervisor solution. Rather it is an applications virtualization solution that is uniquely suited to address some of the unmet needs in desktop virtualization. InstallFree encapsulates applications into Windows OS version independent containers, while providing for execution in VDI, terminal services, distributed desktop hypervisor and fat client Windows modes. A back end management system is used to deploy application images to users and keep them synchronized.
MokaFive’s LivePC images, which contain an entire desktop operating system and application stack that can be run online or offline, boot quickly on a PC, fit easily and securely on a USB flash drive, and update automatically over a network or the Internet. With its unique smart caching and predictive streaming, MokaFive can start up a customized virtual desktop to a Windows or Mac PC in the time it takes to boot a computer. MokaFive also includes a back end authoring and management system designed to create LivePC images and keep them synchronized with images deployed on users’ computers.
Ringcube centrally creates a Virtualized Workspace that consists of all of the user’s applications, customizations and settings. Virtualized Workspaces can be stored locally on a user’s computer and run while disconnected from the network (a laptop), stored on a USB drive for portability while travelling, on a network file share for centralized administration in a branch office, or on a SAN for distribution via VDI. A centralized back end management system creates Virtual Workspaces and synchronizes them with master images.
Unidesk is a management platform designed to sit on top of VDI, fat client, or client side hypervisors. Unidesk is designed to allow IT administrators to have centralized control of OS images and applications, while also allowing users to customize their environments and their applications without creating new instances of images that need to be centrally managed and stored. Unidesk claims to be able to support centralized OS images that cut storage costs by 90%, and require the maintenance of only that one image, while also allowing users to make customizations their environments.
SlickAccess includes a Profile Server which allows IT managers to manage a repository of users’ profiles and to stream users’ profiles to their local PC environments. Streamed applications are then played on the users computer via the Slick Access Remote Applications Player. The Slick Access Management Console keeps profiles in sync between the central profile store and the users devices.
Improvements to VDI
Kaviza is determined to provide a VDI solution that leverages a scale out architecture to provide a dramatically lower cost of purchase and deployment and a dramatically lower cost of operation than traditional VDI solutions. Kaviza does not require a SAN, and simply collects commodity servers with local storage into a resource pool which is managed with a distributed virtual appliance administration system.
While all of the large vendors have offerings in the Desktop Virtualization space, the definition of the space is sufficiently broad, and it is still sufficiently early enough so that small vendors with truly differentiated solutions have a shot at becoming significant players. Enterprises should carefully analyse the requirements for their various groups of users to understand what combinations of technologies fit each group best. Centralized VDI is a good fit for task oriented workers who all need the same set of applications delivered with absolute consistency. Client side hypervisors are a good solution when IT needs to completely lock down an environment, when users have the power to insist on their own flexibility, and when the users are sophisticated enough to be able to switch between two different operating systems and not get confused. Application and workspace isolation solutions lie in the middle of these two extremes offering combinations of both sets of benefits – and have the potential to appeal to the broadest set of users and administrators.