SpeedScreen Latency Reduction Manager

SpeedScreen Latency Reduction Manager

In Chapter 2, "MetaFrame Presentation Server Architecture," we discussed SpeedScreen technology and the way it uses a set of algorithms to update the portion of the screen that has changed rather than refreshing the entire screen. We also discussed how SpeedScreen does this with the help of two features: Local Text Echo and Mouse Click Feedback. In this chapter, we discuss how you can configure the applications on the MPS servers to take advantage of this technology through the SpeedScreen Latency Reduction Manager.

To launch the SpeedScreen Latency Reduction Manager, click Start, Programs, Citrix, Administration Tools, SpeedScreen Latency Reduction Manager. The first window displays the server name and allows you to add an application to take advantage of SpeedScreen. To add an application, follow these steps:

1.	Click New to trigger the Add New Application Wizard.
2.	The first screen informs you what the wizard does. Click Next to continue.
3.	Next, you can browse the application executable. For the purposes of this example, choose notepad.exe and then click Next.
4.	The next window asks whether you want to enable Local Text Echo for this application. It is enabled by default. Click Next.
5.	The next wizard window allows you to apply the SpeedScreen settings to all instances of this application or to just the instance you specified in step 3. If you select to apply to all instances of this application, it registers the executable name, and whenever this application is triggered on this server, it will apply the SpeedScreen settings to it. Applying the settings to the instance you specified applies the SpeedScreen changes to the application only in the way you specified. Choose Apply to All Instances and click Next.
6.	Click Finish to end the Add New Application Wizard.

Now that you have added an application to take advantage of SpeedScreen Latency Reduction, you can further tweak its settings for optimal Local Text Echo performance. If you right-click an application in the SpeedScreen Latency Reduction Manager, you are provided with two options. You can either delete the application or view the application properties, which is where we concentrate our attention next.

Alert

Although configuring SpeedScreen Latency Reduction enables the technology on the server side, a user cannot take advantage of this technology until he or she enables it on the ICA client as well. This topic is discussed in greater detail in Chapter 13, "Citrix ICA Client Software."

Application Properties

The Application Properties window has two main tabs: Application Properties and Input Field Configuration. The Application Properties tab has two main sections. The Application Name section basically displays the name of the application you are currently working on, and the Application Settings section has the following configurable options:

• Disable Local Text Echo for This Application This option is self-explanatory. If checked, it disables the Local Text Echo feature of SpeedScreen technology for this application.

• Limit Local Text Echo for This Application This option offers two settings to choose from. You can configure it so it displays text only in the text fields by selecting Display Text in Place, or you can choose to replace text with bubbles until the server finishes processing and has had enough time to update the client screen, at which point the bubbles are replaced with the actual text. The bubbles are there to acknowledge to the user that "I know you just typed something, but I don't quite know what it is yet." To configure this option, select Display Text in a Floating Bubble.

You can also click the Advanced button and enable Force SpeedScreen to Treat All Input Fields in This Application in Native Mode. If this option is selected, it strips SpeedScreen of the two most important enhancements to it, Mouse Click Feedback and Local Text Echo, and reverts to simply using its algorithms to determine which portion of the screen has been updated and sends refreshes accordingly .

The real configuration of SpeedScreen Latency lies in the Input Fields tab. From this tab, you can tweak every text box or field in an application to respond according to a preconfigured action you specify here. Because different applications have different text fields that need special configuration, the SpeedScreen Latency Reduction Manager provides a wizard that allows you to select the field you want to customize within an application. To do this, follow these steps:

1.	Click New to trigger the wizard and then click Next to bypass the welcome screen.
2.	The next window asks you to launch the application you want to configure fields for. Launch that application, and when it is running, click Next to continue.
3.	After you launch the application, you can drag the icon from the wizard to the text field you want to configure (see Figure 6.8). This action automatically adds that field. You also have the option to hide the SpeedScreen Latency Reduction Manager if it is getting in the way of your ability to select a text field from the application. Click Next to continue. Figure 6.8. Input Field Selection Wizard.
4.	You are presented with a slider that allows you to control generic settings of this input field. Your options are Medium, which is the preferred choice and will use the text window; Low, which you should resort to if the Medium setting does not show the text because it shows the text wrapped in a bubble; and Off, which disables Local Text Echo. Make the appropriate selection and click Next.
5.	Click Finish to exit the wizard.

After you exit the wizard, the newly added input field shows up in the Configured Input Field List. You can now highlight this input field and tweak it even more as follows (see Figure 6.9):

• Limit Local Text Echo This option was described and explained earlier in the "Application Properties" section.

• Reduce Font Size If you enable this option, you can reduce the font size by 10%, 20%, or 30%. This reduction in font size allows for a quicker refresh due to a smaller packet having to travel to the client device.

• Use System Default Colors This option allows you to force the application to use system colors. You can choose Both the Text and Background or The Background Only.

• Input Field Is Password This option instructs Local Text Echo to treat this input field as a password field. You have two options to hide the text being typed. You can choose Hidden Characters Denoted By "*" or Hidden Characters Denoted By Spaces.

Figure 6.9. Input Field Configuration tab.

As with everything else in a server-based computing environment, the best way to know how much to tweak your settings is to test the application until your settings offer an acceptable performance result.

Replicating SpeedScreen Settings to Other Servers in the Farm

In many cases, you may need to replicate the changes you made to the SpeedScreen Latency Reduction Manager to other servers load balancing a particular application. Instead of going through the process on every server, which can be frustrating and time consuming, especially in larger farms, you can copy the settings from one server to another.

After you complete all the configurations and save the settings, the settings are stored on the server in the following location: %systemroot%\system32\ss3config. You can copy this directory to every server you want to inherit this configuration.