Sharp skill for thin clients

Citrix Independent Computing Architecture

Citrix Independent Computing Architecture - Citrix is 56th in the SSL/CW skills list

What is it?

Five years ago the fat client/thin client debate was raging. Fat clients were full-function PCs, stuffed to the gills with locally-held copies of applications. Thin clients were slimline terminals which used the network to access centrally held applications.

Various studies had put the total cost of ownership of a fat client - including purchase costs, licensing and manually upgrading software - at up to $10,000 (£6,500) a year. Thin clients were the future: all administration and the heavy processing would be done at the server. Pure thin clients were closed boxes which users could not modify: they had no floppy or CD drives.

Sadly, in a gut-barging contest, the fat guys have the edge. Nevertheless, the most successful thin-client technology, Citrix Independent Computing Architecture, is thriving, and total costs of ownership have plummeted. SAP users recently voted Citrix Metaframe Access Suite the product with the greatest positive impact on their SAP implementations for the second year running, citing improved performance, lower implementation and management costs and increased flexibility.

Where did it originate?

Citrix Systems was founded in 1989. It specialised in remote access with products such as Winframe.

The Citrix Metaframe application server software, the core of the server-based, thin-client computing strategy, was first shipped in 1998.

What is it for?

ICA is the protocol that enables Citrix to separate screen updates and user input processing from the rest of the applications logic.

All application logic executes on the server and only screen updates, mouse movements and keystrokes are transmitted over the network, requiring just a few kilobits per second of bandwidth.

What makes it special?

Citrix clients can access almost anything that runs on a Citrix server, which means, for example, that a Windows PC can use Linux or AIX applications and that Macintosh and even Dos PC users do not have to change their systems to run Windows applications.

Management is centralised and it is possible to look after a heterogeneous client environment from the server.

Citrix claims its users find a reduction in total cost of ownership for their PC networks of 35% or more. Applications can be deployed more quickly and efficiently, since they only have to be installed once on the server. Client hardware can go on being used long after it would normally need to be replaced to accommodate the latest increase in the size of Windows.

How difficult is it to master?

The foundation course in Metaframe administration takes four days.

Where is it used?

Citrix claims more than 120,000 customers and nearly 50 million users, including all of the Fortune 100 companies, 99% of the Fortune 500 and 95 of the Financial Times European 100.

Not to be confused with...

A lemon-flavoured vitamin supplement.

What systems does it run on?

Windows, Solaris, AIX and other Unix servers; Windows, Macintosh, Unix and a range of other clients, including handheld systems.

What is coming up?

Consolidation of the different Citrix access tools into an integrated suite.


Through Citrix authorised learning centres. See

Jobs and money

From £20,000 to £30,000 for systems analysts, and £40,000 to £60,000 for Citrix consultants and Metaframe architects.

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