Citrix Presentation Server is relied upon by millions of end users to deliver applications securely to any location, any device
over any connection. This unique solution is achieved by an advanced proprietary protocol called the Independent
Computing Architecture (ICA), developed, owned and enhanced by Citrix Systems, Inc. Citrix has continued to enhance the
ICA protocol by including capabilities like compression, encryption, caching, and flow control.
As a significant percentage of Presentation Server customers have their applications delivered over remote WAN links,
finding ways to improve the speed and the end user experience is a goal of WAN optimization solutions. Also, by being able
to tap into such a large pool of potential users is extremely enticing for all WAN optimization organizations.
Unfortunately, many of the claims about WAN optimization improving the ICA protocol speed are based on simulations not
reflecting typical real-world scenarios. Another common issue is focused on terminology used when discussing WAN
optimization. When discussions arise about WAN optimization and ICA, the improvements are usually focused on the
following two areas:
• Accelerating ICA: Actively improving the performance metrics of ICA within real world cases.
• Protecting ICA: Limiting non-ICA traffic from impacting the ICA traffic, which results in decreased performance from the
user's perspective while working on Presentation Server. This area is often referred to as Quality of Service (QoS).
This document explains the common ways WAN optimization solutions function and the truths and myths
associated with these techniques when integrating with Citrix's ICA protocol. Click here to read or download the document.
