Product Reviews

VDI VIP

VMware's Virtual Desktop Infrastructure is better than older versions, but not necessarily appropriate for virtualization beginners.

• By Alan Maddison
• 02/01/2010

Virtualization is all the rage. While most shops have virtualized servers, far fewer have virtualized desktops. That could change with the advent of VMware's Virtual Desktop Infrastructure (VDI) with all its potential benefits, such as manageability, supportability, security and availability.

Released in November 2009, the latest version of VMware's desktop virtualization app is a significant step forward in many areas -- not least of which is its support for the company's vSphere 4 data center virtualization platform.

Breaking Down View 4
View 4 consists of four core software components: View Connection Server, View Agent, View Client and View Composer. View Connection Server brokers client connections, handles authentication, and accesses View Manager for infrastructure administration. View Agent runs on virtual desktops or terminal servers and allows View Manager to manage them, while View Client is the local software application that connects to View Connection Server and lets users access a virtual desktop. Finally, View Composer supports master images and linked clones.

Before you get too excited, keep in mind you also need an ESX or ESXi back-end infrastructure based on vSphere 4 (Update 1), or VMware Infrastructure 3.5 (Update 3 or 4) and vCenter. Together, these components provide a powerful and flexible framework for deploying and maintaining a VDI. It's this centralization of your desktop environment within the data center that drives the benefits associated with a VDI deployment. Storage management is greatly improved through the use of technologies such as View Composer and linked clones, as well as through storage over-commit, which allows you to aggressively manage your changing storage requirements.

Hosting desktops on enterprise-class server hardware and storage dramatically changes the availability and reliability profile for a user's desktop. From a performance and scalability perspective, VMware suggests that View 4 offers up to double the number of virtual machines (VMs) per core than earlier versions. Being able to run up to 16 VMs per processor core is a significant advance. However, this improvement is based on three factors, including the use of vSphere, Nehalem processors and improvements in View 4 itself.

Aside from the inherently greater security of a data center, other improvements include View Composer and linked clones, which streamline the patching process; vSphere's vSafe API; and some of the inherent security features of the PC-over-IP (PCoIP) protocol. With PCoIP, which is now part of View 4, session management is secured using Secure Sockets Layer, and media transfers between host and client are encrypted using Advanced Encryption Standard.

REDMOND RATING Installation 20% 10.0 Features 20% 10.0 Ease of use 20% 9.0 Administration 20% 9.0 Documentation 20% 9.0 Overall Rating: 9.4 Key: 1: Virtually inoperable or nonexistent  5: Average, performs adequately   10: Exceptional

Benefits and Challenges
A virtual desktop environment comes in handy when migrating to new desktop OSes. Aside from streamlining and dramatically speeding the rollout process, VDI lets you upgrade the software without upgrading the physical desktop hardware. But all that work virtualizing desktops is for naught if end users aren't happy. View 4 has significantly improved the end-user experience and is moving toward the ultimate goal of making VDI indistinguishable from a physical desktop.

One such enhancement is the inclusion of Teradici Corp.'s PCoIP protocol. Although PCoIP started as a hardware client, VMware put in time and effort working with Teradici to develop a software solution.

While View 4 continues to support Remote Desktop Protocol (RDP) -- the backbone communications protocol for existing View deployments -- VMware hopes PCoIP will help View leapfrog the competition, which includes Citrix XenDesktop and its HDX technology.

As a protocol designed for delivering virtualized desktops, PCoIP has some impressive capabilities, including built-in compression and encryption to secure your desktop environment and enhance the end-user experience over the WAN. Of particular importance from the end-user perspective is transparent hardware bridging for USB devices.

View 4 also improves local printing, with automated discovery of printers and support for compression of print data. True multi-monitor support is another feature power users will appreciate.

PCoIP also addresses -- but does not completely resolve -- WAN performance issues by ensuring that only differential data at the pixel level is transmitted. In addition, View 4 supports a WAN infrastructure with up to 250MS round-trip latency and 5 percent packet loss. While your users may not be wild about this performance, it does improve the viability of a VDI environment accessed over the WAN. Add in support for local keyboard and mouse to address concerns about user input latency, and VMware has made headway addressing the major WAN concerns.

One of the coolest features is unfortunately still experimental: Offline Desktop. As you might imagine, this lets the complete virtual desktop environment to be moved from the data center to the physical desktop. Any changes made offline are later synchronized back to the data center and preserved in the VDI.

Not for the Uninitiated
View 4 is a compelling enhancement to an already strong product, but how easy is it to deploy and administer? It depends. For a small-scale or pilot implementation, installation is straightforward as long as you have an existing vSphere or VMware Infrastructure environment.

If you don't have an existing ESX environment, you must install the vSphere components, including the ESX hosts and vCenter server, which add time and complexity to the deployment. If you do have a vSphere environment, there are two important considerations. If you purchase View 4 Premier Edition and intend to use View Composer, you must install View 4 on your vCenter server. For most organizations, that requires change control and a maintenance window, so plan accordingly.

Secondly, you must deploy the View client to your end points so that users can access their virtualized desktops. While you will need a dedicated server for the installation of View Connection Server, the process only takes only a couple of minutes, and it's completely wizard-driven.

There are some elements of an advanced configuration, such as pools and tagging, which facilitate desktop provisioning and assignment. Implementing those elements requires pre-planning, but VMware has done a good job keeping overall installation as simple as possible.

While installation and configuration of View 4 is surprisingly uncomplicated, the pre-planning and design work that's required in large environments can be enormous. There are many sizing and design questions that must be accurately answered to ensure a successful rollout of VDI.

Considerations such as storage sizing and performance, memory utilization, and provisioning and network utilization are all important. Add in calculating WAN usage for users who are remote to your ESX environment, and you see the complexity and magnitude that can accompany a large-scale rollout of VDI. If your environment is large enough, you would be best advised to engage VMware Professional Services, at least for the design stage.

This fact alone highlights one obvious concern with View 4: vendor lock-in. There are competitive VDI solutions that are virtualization-infrastructure agnostic -- Citrix XenDesktop, for example -- but View 4 locks you into a VMware back-end environment. For organizations committed to VMware, this won't be a problem. But others should consider this carefully.

A Maturing Technology
VDI may finally be poised for real market acceptance. The primary barrier to has always been the end-user experience. Early versions of VDI software, including View, struggled with local hardware devices, printing, audio and other end-user elements.

In View 4 VDI is overcoming these challenges with transparent hardware bridging, multi-monitor support and rich media capabilities. VMware has finally delivered a virtual desktop experience that is virtually indistinguishable from a physical desktop.

VDI is not a universal panacea for desktop management. There will always be segments of the user population for which a virtualized desktop is not sufficient or appropriate. And for virtualization novices, VDI is a daunting first step. Still, View 4 is an excellent product that addresses major challenges in deploying and managing a virtualized desktop infrastructure. If you have not recently looked at VDI, View 4 is a compelling reason to reexamine the technology.

View 4 comes in two versions, Enterprise and Premier, which offer slightly different functionality. View 4 Enterprise includes vSphere 4 for Desktops, vCenter 4 and View Manager 4. Premier Edition also includes ThinApp 4 and View Composer. Licensing is based on concurrent connections, with the list price for Enterprise Edition set at $150 per concurrent connection, and $250 per concurrent connection for Premier Edition.