Over the past few years, I have talked with several dozen Burton Group clients who are struggling with defining their next generation desktop and application delivery architecture. They often like the idea of the server-hosted virtual desktop, but not the cost. In addition, many of our clients are increasingly looking at cloud-based application delivery frameworks such as software-as-a-service (SaaS) and platform-as-a-service (PaaS). For example, several of our clients use the Salesforce.com customer relationship manager (CRM) SaaS-based application. The result- users get a rich application assessable from anywhere with a web browser, and IT sees a low total cost of ownership (TCO) for the CRM application. Other Burton Group clients have evaluated Microsoft Exchange via SaaS services, while others are keeping an eye on PaaS offerings such as Microsoft Azure.

Besides SaaS and PaaS, infrastructure-as-a-service (IaaS) is increasingly growing in popularity. One of the most common ways to deliver IaaS is by leveraging hardware-infrastructure-as-a-service (HIaaS) platforms (e.g., VMware vCloud, Amazon EC2, or Citrix Cloud Center). For the majority of our clients, their initial entry into HIaaS has started by building private clouds to host applications in virtual machines. HIaaS as a backend for desktop-as-a-service (DaaS) is on the radar of many of our clients. For several, 2010 plans include virtual desktop pilot projects, and small deployments by the fall. Note that while I’m being relatively light on the definitions, you can read Burton Group’s detailed perspective on cloud in the following free report “Cloud Computing: Transforming IT.”

If you’re wondering “What’s the point?” here it is. Application delivery  does not have to begin and end at the virtual desktop, and in many cases will not. SaaS and PaaS services will increasingly play a role in delivering applications to end users. Presentation virtualization technologies such as Citrix’s XenApp will do so as well. XenApp as the delivery mechanism for internal SaaS, combined with the Citrix Receiver, for example, provides the framework to publish Windows applications to a variety of endpoints (e.g., notebook, netbook, iPhone, iPad, thin or zero client, and thick client). So in the end we’re winding up with several layers of application services that need to be seamlessly delivered to the end user. This means that security policy enforcement and identity management, for example, will need to traverse each service layer. For most organizations today, leveraging SaaS applications requires users to maintain a separate login for each provider. Identity federation in support of single sign-on access to cloud services will be a key enabler in the delivery of converged cloud services. Others (e.g., Microsoft and Novell) have tried and failed in the past, but this time the stakes are different. Strong interest in cloud services provides the use case waiting for a solution.

If we take the delivery of converged cloud services to the client endpoint, we get to what should be a divide between two user experience domains: personal space and work space. The endpoint device may include a client hypervisor to securely separate both personal space and work space, as shown below.

Granted, what I’m talking about here isn’t revolutionary. Many vendor examples relating to a bring-your-own-device delivery model highlight the need to separate personal space and work space, but they fall short in their inclusion of other relevant cloud application delivery services. In fact, I blogged about this approach a year ago. Independent analyst Brian Madden went a step further and predicted that 90% of virtual desktops will run on client endpoints.

To summarize, we need to keep the focus of application delivery on the application. If a call center’s application delivery requirements is best suited by a low-end device that uses a web browser to present applications to users via SaaS, then so be be it. If the application delivery requirements warrant a server-hosted virtual desktop, then that’s OK too. Still, in my opinion, IT’s future is about managing each user’s work space, and we should be looking at technologies that simplify delivery and presentation of converged cloud services. The winning vendor, and the one that drives a user’s work and/or personal space, is the one that nails the presentation of converged cloud delivery. I’m not sure who the winner will be, but I know that the winner won’t be the vendor going after this problem with a narrow view of the typical enterprise’s application delivery requirements. What do you think? We will be talking about these topics at Catalyst Europe in Prague next month, and I hope to see you there.