IT shops that prefer server-centric app delivery have had to compromise when it comes to road warriors and users that require graphic- and CPU-intensive applications. These groups just aren’t a good fit for thin clients that run over the network. The result? IT has had to maintain separate application-deployment models to match the needs of disparate populations.

Now comes Citrix Presentation Server (CPS) 4.5, which says IT can have its cake and eat it, too. CPS adds application streaming to its portfolio, which means all the executables, DLLs and other files required to run the application are sent to the client and cached on the local hard drive. The application then executes locally rather than on the server. When we streamed a version of Microsoft Office 2003, this new feature let us do something no other CPS product allowed us to do before-unplug our laptop and still use Microsoft Word.

Of course, you can do exactly the same thing with products such as AppStream’s AppStream.Now and Microsoft’s SoftGrid. So what separates CPS from its more mature application-streaming competitors? Choice. Applications delivered to your CPS server farm can be published for remote display (that is, run as thin clients) or streamed to the client. This is a welcome addition for IT shops that are deploying applications under a number of different scenarios.

That said, CPS still favors thin clients. Its Access Platform Java client lets you run thin clients of Windows applications on any PC, Mac or even Linux machines. By contrast, the new technology only works with Windows.

And CPS customers still must manage software licenses carefully. All apps, whether published for remote-
display or streamed, are licensed concurrently. Streamed applications that are cached always incur a license.

THE NEW & THE OLD

Citrix has also updated its management console. Most functions formerly spread between the MetaFrame server administration and management consoles are now accessible in one place-the Citrix Access Management Console.

But 4.5 still lacks a truly unified console because you can’t perform all the administrative tasks for your server farm from one location. You’ll mange your isolation environments, printers, policies and installation manager packages in a different utility, the “Presentation Server Console.” Citrix says it has plans for a single console, but we’ll have to wait for subsequent versions of the product.

Speaking of subsequent versions, the installation manager-that handy feature from the 4.0 product that makes it easier to package an application for deployment to all the servers in your farm-is superseded by a new tool, the application-streaming profiler.

The profiler collects data from a simulated application install and creates a package from the file and registry data. By copying application profile packages to Windows file shares accessible to all the presentation servers and clients in your enterprise, you can stream the application to the presentation servers, then use the thin-client or application-streaming option. Even if you’re not going to stream apps to your clients right away, it makes sense to deploy them using the application-streaming profiler so you’ll have the streaming option ready to go.

Note: Just make sure to target your server and client operating systems when building the streaming profile. This extra step got us a couple of times in testing because we forgot to select both XP and 2003 as the target OSs.

SPEEDY DELIVERY

Citrix SpeedScreen, a long-running feature that significantly improves the performance of Web applications, Flash playback, and video through various caching and image compression techniques, gets a boost in 4.5 from Progressive Display technology. Progressive Display offers two levels of compression-one for static images and one for moving images. This gives a much-needed kick to applications where the user is panning, zooming and rotating 2-D images around on the screen.

We test-drove this feature using a thin-client of Google Earth and were impressed. Without our Progressive
Display policy activated, Google Earth would take one to two seconds before responding to our mouse movements. With it on, the application latency was noticeably reduced, and the application was usable.

The Platinum edition of CPS 4.5 also includes EdgeSite, an application performance-measurement tool. EdgeSite agents can be installed on both the presentation servers in your farm and client endpoints. They run in the background and collect various CPU, memory, disk, network, session and logon metrics to help you identify bottlenecks. CPS 4.5 Platinum edition is $600 per concurrent user.

The author is a system administrator at Syracuse University’s School of Information Studies. Write to him at mafudge@syr.edu. Post a comment or question on this story at nwc.com/go/ask.html