- Citrix NFuse 1.5: Part 2 - The Role Of The ICA Client
- Application Launching and Embedding with NFuse 1.5
- Strong Encryption Support
- ICA Client Detection and Installation with NFuse 1.5
- Standalone Client Installation Web Sites
Todd is the author of Windows NT/2000 Thin Client Solutions: Implementing Terminal Services and Citrix MetaFrame (New Riders, 2000).
The Citrix ICA Web Clients
A common misconception that people have when they first begin working with NFuse is that a user requires only a Web browser to access published applications within a server farm. Unfortunately, this is not the case. In addition to a Web browser, the user must have a suitable ICA client. There are actually two different types of ICA clients available from Citrix for use with NFuse:
Citrix Application Launching and Embedding (ALE) clientsFour types of ALE clients can be used to connect to an NFuse-published application: an ActiveX control for 32-bit Internet Explorer, two types of Netscape plug-ins (16- and 32-bit), and a Java applet. ALE clients are actually required to access an application that has been "embedded" in a Web page. ALE clients cannot be used to "launch" applications from a Web page. The advantage of using an ALE client is that the installation requirements are minimal in comparison to a traditional Citrix ICA client. Both the ActiveX and Java applets require no installation on the client part, while the plug-ins require that you download and run a simple setup file.
Traditional Citrix ICA clientsThese ship with a "helper" application that can be used to access Web-enabled applications. Not all Citrix clients support NFuse applications, and I will look at this more closely shortly. These "helper" clients are required to allow an application to be "launched" from a Web page. Helper clients cannot be used to access "embedded" applications.
Regardless of the client, the basic function remains the same: to process the contents of the ICA file and to establish the connection to the appropriate published application. Figure 1 demonstrates the role that both the browser and the ICA client play in a user's NFuse session.
Web browser/ICA client role in an NFuse session