Specifications

50 Appendix A
Understanding Session Services
Before you use the information in this section to configure your ICA and RDP session
services, be sure you understand and use the following guidelines:
TIP: Wyse thin clients running Windows Embedded Standard also support virtual desktop
solutions as described in "Using VMware View Manager Services."
• General Guidelines - The Thin-client session services are made available by servers
hosting Citrix ICA and Microsoft RDP software products.
• ICA Guidelines - Independent Computing Architecture (ICA) is a three-tier,
server-based computing technology that separates the logic of an application from its
user interface. The ICA client software installed on the thin client allows the user to
interact with the application GUI, while all of the application processes are executed on
the server. For information on configuring ICA, see
"Configuring ICA Session
Services."
TIP: The ICA server must be licensed from Citrix Systems, Inc. You must purchase
enough client licenses to support the total concurrent thin client load placed on the
Citrix server farm. A failure to connect when all client seats are occupied does not
represent a failure of Wyse equipment. The ICA client software is installed on the thin
client.
• RDP Guidelines - Remote Desktop Protocol (RDP) is a network protocol that allows a
thin client to communicate with the Terminal Service running on Windows 2003/2008
Server over the network. For information on configuring RDP, see
"Configuring RDP
Session Services."
Configuring ICA Session Services
Before you use the information in this section to configure your ICA session services, be
sure you have read "Understanding Session Services."
ICA session services can be made available on the network using either Windows 2003/
2008 Server with Terminal Services and one of the following installed:
• Citrix MetaFrame XP
• Citrix Presentation Server
Use the instructions accompanying these products to install them and make sessions and
applications available to the thin clients sharing the server environment.
TIP: If a Windows 2003/2008 Server or Citrix XenApp 5.0 with Windows Server 2008 is
used, a Terminal Services Client Access License (TSCAL) server must also reside
somewhere accessible on the network. The server will grant a temporary (120-day)
license on an individual device basis. Beyond the temporary (120-day) license, you must
purchase TSCALs and install them on the TSCAL server (you will not be able to make a
connection without a temporary or permanent license).