Independent Computing Architecture (ICA) is a proprietary protocol for an

application server An application server is a server that hosts applications or software that delivers a business application through a communication protocol. An application server framework is a service layer model. It includes software components available to a ...

system, designed by

Citrix Systems Citrix Systems, Inc. is an American multinational cloud computing and virtualization technology company that provides server, application and desktop virtualization, networking, software as a service (SaaS), and cloud computing technologies. C ...

. The protocol lays down a specification for passing data between server and clients, but is not bound to any one platform. Citrix's ICA is an alternative to Microsoft's

Remote Desktop Protocol Remote Desktop Protocol (RDP) is a proprietary protocol developed by Microsoft which provides a user with a graphical interface to connect to another computer over a network connection. The user employs RDP client software for this purpose, while t ...

(RDP). Practical products conforming to ICA are Citrix's

WinFrame Citrix Virtual Apps (formerly WinFrame, MetaFrame, Presentation Server and XenApp) is an application virtualization software produced by Citrix Systems that allows Windows applications to be accessed via individual devices from a shared server o ...

, Citrix XenApp (formerly called MetaFrame/Presentation Server), and Citrix XenDesktop products. These permit ordinary Windows applications to be run on a suitable Windows server, and for any supported client to gain access to those applications. Besides Windows, ICA is also supported on a number of Unix server platforms and can be used to deliver access to applications running on these platforms. The client platforms need not run Windows; for example, there are clients for Mac, Unix, Linux, and various smartphones. ICA client software is also built into various thin client platforms. ICA is broadly similar in purpose to window servers such as the X Window System. It also provides for the feedback of user input from the client to the server, and a variety of means for the server to send graphical output, as well as other media such as audio, from the running application to the client. Key challenges of such an architecture are network latency and performance—a graphically intensive application (as most are when presented using a GUI) being served over a slow or bandwidth-restricted network connection requires considerable compression and optimization to render the application usable by the client. The client machine may be a different platform, and may not have the same GUI routines available locally—in this case the server may need to send the actual bitmap data over the connection. Depending on the client's capabilities, servers may also off-load part of the graphical processing to the client, e.g. to render multimedia content. ICA runs natively over TCP port 1494 or may be encapsulated i
Common Gateway Protocol
(CGP) on TCP 2598. ICA supports the concept of channels at a session layer to encapsulate

rich media Interactive media normally refers to products and services on digital computer-based systems which respond to the user's actions by presenting content such as text, moving image, animation, video and audio. Since its early conception, various f ...

redirection or USB extension within ICA.

Client software

* Citrix ICA Client (DOS, OS/2) * Citrix Presentation Server Client (Mac, Java) * Citrix Receiver (Linux, Unix, Windows, Mac OS X, iOS, Android, Chrome) * Citrix XenApp/XenDesktop Plugin (Windows) * SAP

External links

A Slashdot discussion giving insights on how ICA works

Citrix Systems Remote desktop Remote desktop protocols {{software-eng-stub

Client software

See also

External links