IT service provider offers tens of thousands of customers secure and fast services using Citrix NetScaler

KPN is a leading provider of a wide range of IT and communications-technology services in the Netherlands and other countries. One of its subsidiaries, ApplicationNet BV, offers its customers a complete cloud-based workplace solution, called KPN Werkplek, based on a Microsoft Exchange system, and provides access to customers anywhere, anytime, on any device. KPN’s ApplicationNet BV is based in Groningen, Netherlands, and employs 65 people.

The Challenge: Improving the availability of Microsoft Exchange

KPN has offered online workspaces to its customers since 2002, since discovering that its Citrix server-based systems support the highest number of devices and operating systems. But in 2012, KPN faced a challenge when an upgrade was needed to improve the availability of another service—the hosted Microsoft Exchange environment.

The Solution: Upgrading to a load-balancing solution

KPN decided the best option was to upgrade to a load-balancing solution with Citrix NetScaler. “We use preferred products and solutions from major players such as market leaders HP, Microsoft and Citrix,” says Chris van Meer, a technical specialist at KPN. “We opted for Citrix NetScaler because it’s a quality product with excellent specifications and references."

“In addition, KPN is a Citrix System Integrator, with extensive experience with other Citrix products. But the main reason was that we needed to offer other services—including our KPN Werkplek—through NetScaler to ensure the security, performance and scalability of these services.”

To get the upgrade moving forward, KPN introduced two Citrix NetScaler MPX 8200 load-balancing devices into the mix—one in the datacenter in Aalsmeer and another in Haarlem. The implementation of the devices went smoothly, and soon they discovered that other services were needed.

“After some time, we migrated to two more powerful NetScaler SDX 11515 systems, on which we run multiple virtual NetScaler appliances in HA mode,” says van Meer. “Thanks to virtual NetScaler systems, we are able to maintain a scalable service center while still having separate customer environments. Meanwhile, we are load balancing our core services such as Microsoft Exchange and Microsoft Lync. In addition, NetScaler is the secure gateway for our mobile device management service based on Citrix XenMobile; and we are starting with load balancing as a service using NetScaler.”

Key Benefits

Increasing uptime for 36,000 users

Always-on access is important to KPN; and by using the NetScaler solution, user uptime is guaranteed. For instance, if someone is actively using one server and an issue pops up, another server will automatically switch on without losing any data the user needs. 

“High availability is essential for shared services because a failure would currently affect more than 36,000 users; and the number of customers keeps on growing,” says van Meer. “Once when we had a failure of one of the backend servers, NetScaler handled the problem without our customers noticing anything.”

Enabling virtual desktops with powerful mobility options

The KPN Werkplek virtual desktop service is offered to organizations with 150 or more employees in industries that range from healthcare to media. Citrix XenDesktop is the foundation of KPN Werkplek. The NetScaler device provides secure, redundant and optimized access to Werkplek and can be extended with Citrix XenMobile for mobile device management (MDM).

“Different types of customers are very happy with this option,” says van Meer. “For example, a healthcare provider can work with XenDesktop on all desktops at the office, as well as on a tablet at the patient’s bed. The tablet is managed with XenMobile. But customers who also have a phone subscription appreciate the centrally administered MDM solution to manage mobile devices, such as selectively wiping corporate data.” KPN enables MDM to the customer devices through NetScaler. 

Providing insight into data traffic

NetScaler helps service providers such as KPN to better understand all their data traffic and to optimize and secure that traffic. For example, NetScaler AppFirewall learns the characteristics of the services and, for KPN, blocks unwanted traffic such as SQL injections.  

“The NetScaler devices are currently configured to default, and even without optimization and comprehensive configuration, the load of all services and tens of thousands of users is only a few percent,” says van Meer. “Once you know the devices, they have countless features. The only limiting factor is your own creativity; so anything is possible.”

Looking Ahead

KPN sees a promising future in using Citrix NetScaler. The company is looking to boost its services around cloud and mobile. Its datacenters and Citrix solutions are ready to scale up and serve more customers with virtual desktop accounts, mobile accounts and physical accounts for laptops, with the right mixture between security and freedom.

Copyright © 2015 Citrix Systems Inc. All rights reserved. Citrix, AppFirewall, XenMobile, XenDesktop and NetScaler are trademarks of Citrix Systems Inc., or a subsidiary thereof, and are or may be registered in the U.S. Patent and Trademark Office and other countries. All other trademarks are the property of their respective owners.

We opted for Citrix NetScaler because it’s a quality product with excellent specifications and references.
- Chris van Meer

Technical Specialist



  • Telecommunications

Key Benefits

  • Increases uptime for 36,000 users
  • Enables virtual desktops with powerful mobility options
  • Provides insight into data traffic

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