Taken from Getting Started With Citrix Presentation Server 4.5.
You publish any given application or content once on the server, but multiple users can simultaneously access the published resources. Application processing on the client is kept to a minimum because the application runs entirely on the server. The ICA protocol sends keystrokes, mouse clicks, and screen updates between the server and the client, so to the user of the client device it appears that the software is running locally.
Because applications run on the server and not on the client device, users can connect from any platform. For example, Microsoft Outlook running as a published application looks and feels the same whether the user is connecting from a Windows CE hand-held computer, a Macintosh desktop, or a Linux workstation. You can control user connections to the server to prevent over-consumption of licenses or server resources.
I have to disagree with the statement ‘looks and feels the same’. Even at lan speed, applications typically have a slow response time – that dragging feeling. The ICA protocol makes up for some of this and is a definite improvement over RDP, but it’s not the same as actually running an application locally.
What Nkl Hd says is both True and False at the same time.
I have used CITRIX where it performed extremely well, you would not have known you weren’t working locally and I have also worked on CITRIX where there was horrific lag time. I believe both the CITRIX server hardware (Is there enough CPU power and RAM to do everthing it is being asked to do) and Network saturation have great impact on its overall performance to the end-user.
In one case, we had simply gobbled up all the RAM so the server was slower than molasses, as soon as we added a few DIMs of RAM we were back in business.
So in my humble opinion, CITRIX works great if it is everything it depends on is adequate.
Also, there are settings that can be tweaked to improve user experience, especially if connecting using Dialup.
Will Citrix work if the RDP of the Citrix server is disabled?