How do DaaS providers deliver cloud desktops?
Most DaaS providers offer either session- or client-based desktops. Services differ in the OSes that providers support and the configuration options at IT administrators' disposal.
Desktop-as-a-service providers take different approaches to how they deliver cloud desktops, but they are usually either server-based or client-based.
At the heart of desktop as a service (DaaS) is a cloud infrastructure that includes the resources to host and deliver desktop services. The infrastructure includes a virtualization layer for managing the VMs that host the cloud desktops, which are then delivered to client devices via a display protocol, similar to an on-premises virtual desktop infrastructure.
Not all approaches to cloud desktop delivery are the same, however. The differences come in the operating system that runs in each VM and how that OS is set up to deliver desktop services.
DaaS delivery options
Cloud desktop delivery was traditionally limited to two basic approaches: server-based and client-based. Most server-based desktops are implemented through Windows Server Remote Desktop Services. In this model, Windows Server runs in a VM and is configured as a Remote Desktop Session Host (RDSH) that supports simultaneous desktop sessions where each session is associated with a single user. For this reason, the server-based model is sometimes referred to as session-based or RDHS-based.
Regardless of the name, the model makes it possible for multiple users to connect to a single VM that runs Windows Server, which helps streamline resource usage and management. From the user's perspective, cloud desktops appear to be a standard Windows client environment.
In the client-based model, each VM runs Windows 7, Windows 10 or a Linux distribution. The VM supports only one user at a time, similar to persistent VDI. The advantage is the VM's resources are dedicated to a single desktop and, therefore, do not suffer the resource contention that can occur with the server-based model. The client-based model also provides more flexibility when it comes to running applications and configuring the environment.
A client-based desktop can also include features that are not available to a server-based desktop, such as support for Cortana or Office 365 ProPlus. The client-based desktop also offers more consistency across an organization when managing both virtual and physical desktops. For example, IT can use a single base Windows image for both types of cloud desktops, apply service packs across all systems and support the same lifecycles.
The flip side to this is the client-based model tends to require more resources and can be more complex to implement and support. In addition, licensing can be trickier than with server-based desktops. Regardless of the differences between the two models, both deliver the full desktop experience and support persistent and nonpersistent desktops.