The advantages of SaaS apps are obvious. You don’t have to maintain and host complex frontend and backend systems. You can roll out updates to users without really being dependent on their client devices. And you can drive innovation rapidly by using artificial intelligence or microservices. That’s why many Citrix customers are transitioning to SaaS apps as fast as possible.

The reality is, the majority of the install bases I see are still based on native Windows applications, which means apps are installed directly on the user’s endpoint device or Citrix Virtual Apps and Desktops workloads. According to the VDI Like a Pro 2021 report, native Windows apps still represent 70 percent of all apps.

I’m a firm believer that, like the public cloud transition, the app landscape will remain hybrid for a very long time. Many companies have homegrown apps, have invested a lot in infrastructure, are already realizing cost efficiencies, and have regulatory obligations that make a SaaS transition impossible. Moreover, migrating complex apps to a web- or SaaS-based platform sometimes requires sizable investment and might not return value in enough time.

Use Case Overview

This is a scenario I’ve seen at many of my customers. One of our largest manufacturing customers in EMEA has about 6,000 apps, with about 95 percent hosted on premises. Native Windows apps account for about 80 percent of all their apps, and 4,800 apps are still installed on endpoints and/or Citrix workloads.

This customer has more than 200,000 users worldwide, and rolling out apps to endpoint devices is one of its biggest challenges. In some cases, updating an app on all devices can take 2.5 months. The situation today is even more challenging because many employees are working remotely and not all have a stable networking connection. As a result, regular updates are rare, which can have a negative impact on line-of-business innovation.

One of the customer’s main objectives is to become more agile, and we’re working with their teams to identify ways to improve their operational model to enable IT teams to reduce the app-rollout duration (see also Evaluating Application Delivery Methods).

To assess and compare the general implications, efforts, and overall rollout duration of an endpoint versus a Citrix deployment, the customer chose SAP GUI as the reference application. SAP GUI is a business-critical app, is natively installed on 70,000 endpoints worldwide, and is also provided through Citrix Virtual Apps and Desktops in parallel. Today, the customer can only conduct two major releases per year, so many different changes with numerous dependencies must be combined and applied at once. As a result, the SAP releases are considered complex.

Assessment Results

The following data for the endpoint and Citrix rollout duration were provided by the respective customer teams. The efforts and duration include all the major activities related to a single SAP GUI release. To be able to compare the activities, the release process was segmented into six phases: Change Management, Application Packing, Testing, Rollout Preparation, Rollout, and Troubleshooting.

Change Management

Endpoint: 3 days (effort)

Citrix: 3 days (effort)

The change management process for both deployment types is identical.

Application Packaging

Endpoint: 7 days (effort)

Citrix: 8 days (effort)

Application packaging efforts are considered higher on Citrix platforms than endpoint installations. According to the customer, the packing on Citrix can take longer because of the multi-user requirement.

Testing

Endpoint: 4 days (effort)

Citrix: 3 days (effort)

The endpoint devices are not consistent, so additional tests have to be conducted. Because Provisioning Services is used with Citrix, the image approach ensures consistency. The customer calculated 20 percent more testing effort in an endpoint environment.

Rollout Preparation

Endpoint: 5 days (effort)

Citrix: 2 days (effort)

The customer is using SCCM to deploy the apps on the endpoints. Over the course of the rollout phase, the customer estimated five days of effort to coordinate and orchestrate the packages in a global endpoint rollout scenario.

Although SCCM is also used in a Citrix environment, once the image is created, the distribution to other global data centers is done via Robocopy and eventually integrated in Citrix Provisioning Services. According to the customer, the rollout preparation with Citrix is 60 percent less compared to an endpoint deployment process.

Please note, the customer’s Citrix SAP GUI installation does not have the same extent of localization settings (language) as the endpoint installation. Further preparation work might apply during application packaging and rollout preparation.

Rollout

Endpoint: 40 days (duration)

Citrix: 4 days (duration)

The biggest difference happens with the rollout. In an endpoint environment, the rollout is conducted in phases. The deployment stages are separated by regions, countries, and departments. Moreover, the installation must be conducted 70,000 times. This leads to a rollout duration of 40 days. However, even after 40 days, only 90 percent of all endpoints are updated. Nevertheless, the customer considers this as completed, because many endpoints do not connect frequently to the corporate network, and it is almost impossible to have a completion rate of 100 percent.

With Citrix, a global rollout can be in theory executed overnight (one reboot needed). Due to change and risk management reasons, the rollout is done over four nights. An image management approach is used, so all servers are updated at once and are consistent with a single reboot.

Troubleshooting

Endpoint: 12 days (effort)

Citrix: 4 days (effort)

Due to the complex SAP releases, the customer estimates a 0.4 percent installation failure rate on endpoint devices. That turns into 280 users being affected per release, as well as support tickets to solve the problem.

Because the installation is done only once with Citrix, the installation failure rate is not relevant. Nevertheless, profiles might be impacted by the update. The customer calculates a profile failure rate of 0.15 percent, which means that 105 user profiles have to be fixed after every release.

Conclusion

In total, the end to end rollout process was 39 day faster with Citrix. Based on these results, the customer came to the following conclusions:

  • With a lower release duration, more releases can be executed annually.
  • Because of the higher release cadence via Citrix, the complexity of the release can be reduced.
  • Managing remote workers will be simpler because hurdles such as updating apps through bad VPN connections are removed.
  • Operational efforts can be significantly reduced due to a process that’s less prone to failure.
  • Urgent application release and security updates can be applied almost immediately.
  • The installation process on endpoints can affect users during working hours (in worst case, the SAP GUI installation can take up to one hour), while a Citrix-based deployment can happen without affecting users.

Ultimately, the Citrix rollout process helps the customer be more agile. To reduce the complexity and dependencies on the endpoint devices, the customer aims to transition all applications where a backend connection is required to Citrix. This gives the customer a SaaS-like experience, at least on the frontend.

Thanks for reading, and a big thanks to my colleagues Robert Wölfer, Holger Marggrander, and Cor Quist for helping me to shape this post. Connect with me on LinkedIn or Twitter, and please share your thoughts in the comments below.