APPLICATION STRATEGIES

The idea behind building an access platform in the first place is to provide a means of distributing common applications to users that is low in cost and complexity, but high in functionality and performance. It is important to keep this "end state" in mind when selecting or writing applications to be run in a Citrix Presentation Server environment. An application that is not stable in a traditional distributed computing network isn't likely to work any better under Presentation Server. In fact, it may exhibit new problems. It is also critical to take the client environment into account. If both PCs and Windows terminals are being evaluated, the capabilities and user experience of each can be quite different and will affect application functionality.

All application installation and updates, even minor hotfixes, must be subjected to a strict systematic installation and testing methodology. From a high level, we suggest the following methodology:

  1. Identify and confirm the requirement for the installation, update, or hotfix .

  2. Research the manufacturer instructions and warnings for the software to be installed.

  3. If the fix is simply a hotfix or software update, utilize Presentation Server Installation Manager (IM) to unpublish (uninstall) the current version of the software from the test environment. Reinstall the original application using IM. Although this process may seem unnecessary, it is critical, as it ensures a common starting point when the update is propagated to other servers.

  4. Install the application in the test environment.

    • Decide whether to install it normally or utilize the isolation environment.

    • Configure the application.

  5. Perform the testing algorithm recommended in the application testing section of this chapter.

    • Make any necessary fixes, Registry changes, or optimizations.

  6. Following full testing, use IM to publish the application to one production server. If it is an update or hotfix, utilize the IM image that includes the full uninstalla-tion and reinstallation as recommended in Step 3.

  7. Re-perform the testing algorithm.

  8. Publish to the remaining required production servers.

Application Features and Requirements

We have created the following list of features and requirements to aid you in the application selection process:

  • Applications should be stable and perform well in a traditional, distributed computing environment.

  • The application should have stated support from the manufacturer. In the early days of on-demand access technology, application support was hit or miss (more miss than hit). With Windows 2000 Server, and now Windows Server 2003, however, in order for a software package to gain the Microsoft Windows Certification, the application must also support execution under Terminal Services. As such, multiuser support has become the norm rather than the exception.

  • Ideally, an application should execute in multithreaded fashion and make efficient use of memory and CPU resources when running in a multiuser environment. Note that this precludes DOS and all 16-bit applications, although there are tricks we will discuss later in this chapter that may allow them to limp by.

  • The use of multimedia in applications should be kept to an absolute minimum. Sound, graphics, or video should be limited to mission-critical features only, because the complexity and cost of the extra network bandwidth consumed by these features must be justified.

  • The application should make the most use of the Windows printing system and be as efficient as possible in the creation and distribution of print jobs. Here again, we issue a warning regarding graphic- intensive programs: they typically generate enormous print files that then travel over the LAN or WAN to the printer. This must be taken into account when planning for the management of the available bandwidth.



Citrix Access Suite 4 for Windows Server 2003. The Official Guide
Citrix Access Suite 4 for Windows Server 2003: The Official Guide, Third Edition
ISBN: 0072262893
EAN: 2147483647
Year: 2004
Pages: 137

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net