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Organizations considering different virtual desktop software vendors should compare offerings such as Windows Virtual Desktop and Citrix in terms of features, cost and, most importantly, end-user experience.
WVD is directly integrated with Microsoft Azure Resource Manager, which enables easier automation and provides simpler management options. Citrix Virtual Apps and Desktops (CVAD), on the other hand, has been in the virtualization market longer and has a broad range of existing offerings.
To determine what the best virtual desktop software is for an organization, IT admins and executives making purchase decisions should learn how these two vendors' offerings stack up against one another.
Flexibility and scalability
Citrix has been investing heavily into cross-platform support to provide integration with any platform, and it offers enhanced support for Google Cloud image management and machine provisioning. This means that CVAD can provide provisioning against multiple on-premises platforms, such as Citrix Hypervisor and VMware vSphere, and Hyper-V or cloud platforms, such as Google Cloud, AWS and Microsoft Azure.
Citrix also provides a lot more flexibility than Microsoft WVD when it comes to deployment options, traffic steering, support for double-hop scenarios and complex Active Directory (AD) topologies. Microsoft WVD has a simplified architecture with the control and data plane running as hosted services in Azure, so the only component that customers are required to operate is the VDI machines. This means that WVD customers have limited options on how to steer traffic, and the only current option is direct Remote Desktop Protocol. This feature requires the endpoint to connect to the session host, communicate with it directly and bypass the WVD gateway. Citrix is clearly the winner in terms of flexibility.
For scalability, there are no known limits when it comes to how far WVD can scale as a service, but it only supports Azure, while Citrix can be used against multiple cloud platforms at the same time. Citrix also enables business continuity and disaster recovery, so it seems that Citrix can provide more scalability.
Many VDI admins use Citrix virtual desktop software for the ease of image management. Citrix provides both Provisioning Services, which uses network-based image streaming, and Machine Creation Services, which uses storage to provision machines based upon cloning. WVD, in its current form, lacks a quality native image management option. However, being native to Azure means that WVD admins can use other means to access the same capabilities. This includes the use of features such as Azure Image Builder, which enables IT admins to automate Azure VM image creation using a set of configuration files.
While Image Builder is one part of the image management process, it is not natively integrated with WVD to provide an automated provisioning of VMs based upon a new image. Therefore, Citrix provides superior image management options that are integrated with its offering.
Azure Image Builder is a generic Azure service, so IT admins can also combine it with Citrix's services to build an initial golden image.
Microsoft acquired FSLogix in 2018 to provide application provisioning capabilities as part of WVD, and it is now the de facto standard in terms of profile management. This is especially true with Office 365 Containers, which enable WVD customers to store and optimize the use of Office 365 in a virtual environment. Since Microsoft acquired FSLogix, it has also changed the licensing approach for FSLogix's offering; FSLogix is available for all workloads using terminal servers or VDI.
Regardless of whether customers use WVD or Citrix, they can use FSLogix's technology. One valuable component that Citrix provides as part of its profile management is application layering. Application layering typically enables IT admins to manage applications in a nonpersistent environment. With CVAD, however, Citrix introduces a user personalization layer that creates a virtual hard disk that stores any applications the user installs locally. This enables end users to install applications on their own, while still running a desktop based on a golden image.
Citrix customers can also provide their own third-party profile management platform, but most organizations will likely stick with FSLogix. If there are any additional requirements, CVAD's app layering can provide additional flexibility.
While WVD is aimed at providing access to Windows applications and desktops, Citrix aims higher in terms of delivering any application. CVAD can provide desktops access to other OSes, such as Linux, and web-based applications that are integrated into their gateway component. The offering can also provide remote access capabilities to computers using their remote PC functionality, which is included in their cloud offering.
Looking at WVD as a standalone offering, the app delivery functionality is somewhat limited. However, Microsoft has other offerings in the Azure ecosystem that WVD customers can use in combination with WVD to provide access to other applications. Azure AD Application Proxy, for example, can provide access to web applications that are integrated into Azure AD. The only downside is that WVD and applications that are available from Azure AD are still two different portals that the users need to access.
Citrix can also provide always-on VPN capabilities for services or applications that still require that type of network access. This feature is also available in Azure but as a separate feature. But, once again, Citrix has more capability as a centralized platform that can provide any type of application. WVD, on the other hand, solely focuses on Windows applications and desktops.
Both vendors provide secure access to their services and a secure management plane. Both offerings can integrate with Azure AD and use conditional access policies to ensure that end users can only have access from certain devices and locations or if Azure AD deems the sign-in as low risk. Another interesting addition is that Citrix provides anti-keylogging and anti-screen capturing capabilities, which is something that WVD currently has in its roadmap but is not yet generally available.
One thing that turns security in Citrix's favor is its analytics engine, which essentially monitors end-user behavior in real time and uses machine learning to monitor user risk. This could detect insider risks or if someone managed to access a legitimate user account and tried to obtain private information or data that they shouldn't be able to access. This type of real-time insight into user sessions is not something that Microsoft currently has with WVD, but once again, WVD can bolster its feature set with Azure AD.
Regardless of which of these platforms organizations use to build virtual desktops in Azure, they must configure a solid foundation using the other built-in tools and features that both Microsoft and Citrix offer.
The most important aspect of delivering and building this type of service is how it works for the end users. Some examples of how to measure end-user experience are as follows:
- How easy is it for the end user to access the application or desktop -- i.e., integration with a local desktop and providing single sign-on (SSO)?
- How does the service or application adjust according to the network, and how well does it perform? Essentially, does the application or desktop feel and behave like any other application on the end-user desktop?
- How is the desktop's integration with other peripherals on the end-user device and other local software?
Looking at both vendors, they each provide a web-based and desktop client to access the environment. However, when it comes to SSO, Citrix is a bit ahead of the game -- especially when it comes to Azure AD. WVD only supports Azure AD SSO through AD Federation Services, while Citrix does this through its Federated Authentication Service (FAS) component. Citrix's FAS essentially enables Windows 10 clients connected to Azure AD to authenticate via SSO directly into their desktop or application using that identity integration.
The second aspect is the network protocol. Both vendors provide a gateway service, which essentially means that IT has to route the traffic through their service and then to the back-end VDI or session host. However, WVD still only supports TCP-based connections, while Citrix HDX supports TCP and User Datagram Protocol-based transfers to provide a more fluent connection. Secondly, HDX is much more adaptive when it comes to bad network connections with high packet loss or high latency.
The last factor to consider is integration with peripherals and integration with local software, such as Microsoft Teams. WVD supports the same level of peripherals as Remote Desktop Services (RDS), which is somewhat on the same level as Citrix. However, when it comes to the speed of these integrations for tasks such as file mapping, Citrix provides a stronger and faster connection that enables faster file transfer between mapped drives in a session.
In terms of support for Microsoft Teams, Citrix has long had an optimization pack that is essentially an extension to Teams to enable video and audio offloading on the device. This way, the session server or VDI is not processing the video and audio. Microsoft has also made a similar offloading client for WVD, which uses a reverse web socket connection to route the traffic back to the end client and process the video and audio there. The only downside to the way Microsoft has done this is that it is only supported on Windows 10.
In terms of end-user experience, Citrix has a stronger ecosystem and a wider range of integrations compared to WVD.
It's important to look at the cost as a function of the available features and not as a standalone number. The WVD service itself is bundled with other Microsoft 365 licenses, which means that customers with a Microsoft 365 Business Premium license, for example, are entitled to use the WVD service. These bundles make it more cost-effective for existing Microsoft customers to deploy WVD desktops to their users. Organizations with per-user licenses of Microsoft 365 E3/E5, for example, are eligible for access to WVD.
The second aspect is multiuser Windows 10 licensing, which grants multiple users access on the same license. This means that IT admins deploying WVD only need to pay for the Azure infrastructure resources they use. The last piece that customers may need is RDS licensing if they plan to run WVD on terminal servers.
With Citrix, customers need to pay additional licensing to access other features in the Citrix ecosystem, but CVAD can also benefit from multiuser Windows 10 to reduce the cost of RDS licensing.
It's difficult to give an exact price estimate for WVD that can apply to every given situation. For example, a Microsoft 365 E3 license, which is a popular license that Microsoft offers, costs $32 per user per month. This license includes Office 365, Windows 10 and, most importantly, access to WVD. Similar access to CVAD is available with the Citrix Workspace Premium Plus license, which costs $25 per user per month but offers fewer bundled resources.
CVAD vs. WVD conclusion
Microsoft has come a long way already with WVD, and it is now an Azure native citizen. Microsoft customers will likely see a lot of new features and enhancements ahead.
Still, WVD is one small part of the Azure ecosystem, so it will never compare to the other larger vendors in the VDI market, such as Citrix, when it comes to features, functionality and end-user experience. However, WVD might be good enough for many organizations, and these customers might make the switch for the cost savings. However, it's difficult to put a price on end-user experience.