Citrix XenApp (originally called MetaFrame and later Presentation Server) is the leading platform for virtualizing Windows applications and can be a vital component in a virtualized information system. The basic idea behind virtualizing applications is to store, maintain, patch, and upgrade a single "Golden" copy of each business-critical program or suite, such as Microsoft Office, on an application hub in a datacenter. The applications can then be securely accessed by remote end users, limited only by network bandwidth, datacenter capacity, and user licenses. By virtualizing application delivery and simplifying management to a single instance of each program, XenApp can dramatically reduce the costs of IT administration and desktop support.
For server-based application virtualization, which is what Citrix is best known for, users can access an application on-demand over the Internet, but the application is actually executed on servers in a remote datacenter. Under the client-side model, users stream the latest version of a virtualized application from the datacenter to their local computers, which makes it possible to run the software offline when an Internet connection is unavailable. Citrix XenApp supports both application delivery models as well as a hybrid dual-mode approach. In all cases, XenApp can cut maintenance and support costs in half, enhance security and compliance, and allow you to run Windows applications on more than 30 operating systems, including Mac, iOS, and all major versions of Linux. XenApp also offers advanced features such as support for server farms for load balancing and fault tolerance.
Progent's Citrix-certified consultants can help you design, implement, and support a virtual application delivery solution based on XenApp. Progent's Cisco-certified CCIE network engineers can help you optimize your infrastructure for delivering server-side and client-side applications, and Progent's datacenter support experts can help you manage and support an in-house or remote datacenter that features high uptime, enhanced security, and fast disaster recovery.
Citrix XenApp Server-side Application Delivery
With XenApp's server-side application virtualization, Windows programs run on a server in the datacenter. Only keystrokes and mouse activity are passed from the end user's computer to the datacenter, and the remote server running the virtualization application transfers only screen updates to the end user.
Because this scheme allows high-speed servers in the datacenter to handle almost all of the client and server processing, the bandwidth demands on the wide area network connection are minimal while the person using the virtualized application has the same experience as though the application were installed on the local computer. Functions such as switching between applications, cut and paste between applications, and accessing local disk drives and printers are all supported without compromising performance. Advantages of service-side application virtualization include centralized application maintenance and version control, fast deployment of new programs and retirement of outdated ones, and the ability to run multiple generations of applications simultaneously to avoid productivity losses while getting up to speed on radical new versions of business-critical software.
Citrix XenApp Client-side Application Delivery
For situations where remote access to the datacenter is not guaranteed, XenApp also supports client-side application virtualization. In this scenario, applications are streamed from the datacenter to the end user's computer where they can be run in an isolated, "fenced-in" environment rather than directly installed. This allows the Windows applications to be run offline and avoids troublesome issues such as software application conflicts, insufficient system resources, and operating system instability. The end user downloads the latest, updated versions of virtualized applications as soon as a network connection is re-established. Client-side application virtualization cuts the expenses and hassle associated with regression testing on the end user's computer and streamlines application distribution, updating, revision management, and decommissioning.
For applications intended to be run offline, Citrix offers utilities like RADEDEPLOY to allow end users to stream programs from the Application Hub at off-peak hours to preserve system responsiveness. For branch office workstations, Citrix offers the Alternate Package Locations tool, which can be configured to allow clients to stream files from an Application Hub on a local network rather than from the remote datacenter.
Citrix Receiver for iOS, Android and BlackBerry Smartphones and Tablets
Versions of the Citrix Receiver for XenApp are available for Apple iPhones and iPads, Android phones and tablets, and BlackBerries. Citrix Receiver allows you to access XenApp hosted applications so you can view, edit and collaborate with Windows applications, documents, and data the same way as you can with a PC. Progent can help you integrate smartphones and tablets into your XenApp environment by providing Apple iPhone consulting services, Android smartphone and tablet integration support, and RIM BlackBerry expertise.
Combining XenApp with XenServer for Enterprise-class Scalability
XenApp can be combined effectively with Citrix XenServer to create a virtual server farm capable of supporting an enterprise-class application delivery system. XenApp has been proven to handle more than 70,000 users on more than 1,000 virtual servers. XenApp incorporates built-in load testing and performance tracking tools that make it possible to expand capacity quickly whenever necessary without sacrificing responsiveness. Progent's XenServer consultants can help you integrate XenApp with XenServer and other virtualization platforms from Citrix and Microsoft to build a virtual application solution that is cost effective, scalable, secure, fault tolerant, recoverable, and easy to manage and support.
How Progent's Consultants Can Help You with Citrix Virtualization Technology
Progent's Citrix certified consulting experts can assist you to assess, deploy, and maintain XenApp and can help you with other Citrix virtualization platforms by providing Citrix XenDesktop expertise, Citrix XenServer consulting services, and Citrix Essentials for Hyper-V support. Progent can also help you configure and manage Citrix Access Gateway, a powerful web-based SSL VPN solution for secure remote connectivity which features highly flexible access control for network administrators.
Progent's Cisco certified CCIE network consultants can show you how to enhance your infrastructure to accommodate Citrix virtualization platforms and Progent's disaster recovery specialists can help you create and test a business continuity plan that takes advantage of Citrix technology. To enhance network security and verify compliance, Progent's certified security specialists can perform comprehensive security assessment testing. Progent can also provide datacenter design and management services and offers remote and onsite datacenter migration and troubleshooting support.
For additional information about Progent's integration and support services for Citrix technology, call Progent at