VDI vs DaaS - How Do You Choose?

It's worth noting that, while the user experience is the most important criterion of success, in most cases your decision to choose VDI or DaaS will be based on business and IT considerations; end-users care more about having the best tools to get work done than where those tools come from. For them it doesn't matter if it's VDI or a DaaS solution like Amazon Workspace, Citrix Cloud, Nutanix Xi Frame, Microsoft WVD, or VMware Horizon.

So How Do You Choose?​

Which option you choose ultimately comes down to your use cases, organizational capabilities, and overall business needs. The following table compares VDI and DaaS in five major areas where significant differences exist. I'll look at each of these areas in turn.

Organization Capability​

From the standpoint of your IT department, it's important to ask whether you have the resources, the expertise, and a compelling need to practice “the art of VDI” or if you would be better off consuming your virtual desktops and applications “as a service”?

Every virtual application and desktop environment needs a broker—a control plane—that's responsible for tasks like provisioning user sessions and ensuring users get secure access to the correct resources. The broker also handles capacity management, infrastructure orchestration, image deployment, and remote display traffic among many other tasks. (See blog 4 for more details.)

With VDI, your EUC team is responsible for designing, installing, securing, and managing the whole platform including the broker—this has substantial complexity. With DaaS, the control plane is a managed service operated by the DaaS provider.

If you don't have the staffing or the expertise to take on the responsibility of managing VDI, if you need to leverage cloud resources to support your use cases, or if you simply have enough on your plate already, DaaS is a better choice.

Platform​

Because someone else is responsible for the broker, you necessarily give up a level of control with DaaS, and access to the control plane requires internet connectivity. This is something to keep in mind when evaluating the use cases for DaaS. A potential DaaS advantage is fast update cycles, a DaaS solution may get better on a weekly basis. DaaS is an emerging technology that supports many of the same use cases as VDI. By leveraging global datacenter scale and flexible infrastructure subscriptions, it also unlocks new use cases.

With VDI, your team is responsible for updating the VDI platform, including secure network services. Often, new versions of the VDI platform are only deployed on a yearly basis. Potential VDI advantages are that it is a mature, tested, and proven solution. Customers exist running 290,000 concurrent users sessions.

If your primary objective is to deploy an environment where you have complete control over the broker, security, locality, etc. VDI is a better choice. For example, if you're in a heavily regulated industry or need to run your virtual applications and desktop without any connection or dependency on the cloud.

Cost​

The cost of virtual desktops and applications is almost always a primary concern. With a VDI deployment, significant capital expense (CapEx) results from upfront infrastructure costs, scaling costs, and periodic infrastructure refreshes. DaaS offers more flexible consumption models. You can run all user applications/desktops in the cloud, resulting in an entirely OpEx model. With some solutions you can run some or all user applications/desktops using on-premises infrastructure (with the broker as a cloud service), blending CapEx and OpEx.

If you have a well-defined usage pattern with predictable growth (and aren't facing resource constraints), VDI—or DaaS with user applications/desktops running on-premises—are the most cost-effective deployment options.

Agility and Elasticity​

If you have a usage pattern that requires greater flexibility or elasticity, then DaaS has some clear advantages. For example, if one of your requirements is to accommodate temporary, seasonal, or contract workers, then it makes sense to choose a DaaS option where you can add seats when you need them—and pay only while you are using them—without sunk capital costs.

If time is of the essence, you can get a DaaS deployment up and running quickly. For example, customers typically deploy Xi Frame in a matter of hours or days. And, if you need to track the latest technology trends—including keeping up with software innovations and the latest CPU and GPU hardware—DaaS can make that easier. With VDI, it often takes organizations a long time to accomplish software upgrades, and you may be constrained by budget and refresh cycles.

Geography​

A final thing to think about is where your users are and where the data is. If you need to support end-users in multiple regions, then DaaS can make that simpler. Also, if data is stored and processed in the public cloud, it makes sense to run virtual applications and desktops close to the data.

With VDI, you'll need a deployment in reasonable proximity to each supported location. Proximity in this context typically translates to lower network latency. High latency—when the datacenter is too far from users—and low bandwidth can have a huge impact on user experience with many remote display protocols. Choose your datacenter and/or cloud regions wisely to support end-users locally or globally.

By choosing the right DaaS solution, you can support all users from the cloud with user VMs in different zones to deliver the best user experience. Alternatively, you can use the cloud as a control plane for all regions, with user VMs running on-premises in some or all locations.

Next Steps​

If these guidelines are steering you towards VDI, be sure and read blog 3 on the advantages of Nutanix HCI for VDI. If you're leaning towards DaaS—or just curious to learn more—the next blog will look deeper at ways to ensure a successful DaaS deployment.

Blogs in This series​

1. Why Should You Care About VDI and Desktop-as-a-Service?
2. VDI Challenges and How to Solve Them
3. How Nutanix Solves the Top VDI Deployment Challenges
4. What Is DaaS and Why Should You Care?
5. VDI versus DaaS: How Do You Choose? (this blog)