Citrix XenApp: Technical Information

How application virtualisation works

Usually only one person at a time can log into and run software on a Microsoft Windows computer. This means each person needs a powerful PC with its own copy of Windows on it. This increases costs and support while reducing reliability. In the mid 90's, Citrix® developed a multi-user version of Windows that allows users to log in from remote clients. This means you only need one copy of Windows for each server and software only needs to be installed once too. Remote clients use a protocol called ICA to access the server.

Versions of Windows Server from NT Terminal Server Edition onwards includes multi-user Windows technology called Terminal Services. Microsoft licensed the core of this from Citrix®; they did not write it themselves. Clearly, this means Citrix® have an unparalleled knowledge of the innards of Windows and extending and enhancing Terminal Services. This is highlighted by Microsoft declaring Citrix® their Global ISV Partner of the Year on multiple occasions. Other bolt-on products cannot hope to achieve the same levels of integration and performance.

Citrix XenApp enables schools to reduce the costs of delivering applications dramatically by centralising management, security and control of applications and data. Through application virtualisation technology, XenApp provides a flexible application delivery system that can select the best method dynamically, based on the user, application and network.

Delivery applications to any device

Terminal Services includes a protocol called RDP which clients can use to access remote desktops, but this is somewhat limited. By using their own ICA protocol, which is much more mature and feature-rich than Microsoft's RDP, Citrix can deliver higher performance and a richer user experience. Client device access (local storage (e.g. USB pens), serial ports, printers, parallel ports, scanners, clipboard, sound output/input) is significantly better supported.

Client software is available for a wider variety of platforms than RDP and offers tighter integration with the client operating system. For example, Citrix® applications can be seamlessly integrated with local applications. Local resources, such as media players, can be used to accelerate multimedia performance. ICA supports user-to-user shadowing, so you can do broadcasted demonstrations (all users view the screen of a demo user) or allow staff to view pupils.

XenApp Features

(Feature vary by edition).

• As an end-to-end application delivery system, XenApp improves performance, increases security and drives down the cost of delivering Windows-based applications. XenApp is the only solution that integrates such a comprehensive set of features, enabling it to become a strategic part of your application delivery infrastructure (features vary with product edition).
• Application performance monitoring, powered by Citrix EdgeSight. These monitoring capabilities enable the support team to quickly pinpoint and troubleshoot application issues that impact the user experience.
• Single sign-on, powered by Citrix Password Manager, secures and automates application logons, enforces password policies and provides self-service password reset.
• SmartAuditor provides powerful application session recording for improved regulatory compliance, risk mitigation and accelerated problem resolution.
• Preferential load balancing prioritises key users and applications to ensure the best performance of hosted applications.
• Application hub stores isolated applications centrally and provision applications and updates rapidly without disrupting users or causing application or system conflicts.
• Increases user density per server dramatically, reducing costs for hardware acquisition, electricity, cooling, as well as for management and maintenance. This is achieved using CPU and Virtual Memory optimisation.
• Citrix XenApp Web Interface provides users with a single location for access to all curriculum content and applications.

Why Precedence?

Staff from Precedence Technologies have been Citrix Authorised since 1998 which, coupled with a longe-stablished education focus, means Precedence is uniquely placed to deliver a reliable and effective thin-client system for your school.