Building and configuring an ACP thin client network requires three types of hardware and three types of software. This document will provide an overview of the process and provide links to more detailed articles.
The three hardware components are: |
The three software components are: |
The most important component of the server hardware is memory (RAM). Each terminal user that logs into the server will have a self-contained session requiring enough RAM to run its applications. To determine the quantity needed, add the amount needed for each session to the 128 MB needed for the operating system. While 16 MB may be enough for an office terminal running a word processor and an e-mail program, HMIs and SCADA programs require higher amounts. Plan on 64 to 128 MB for each HMI operator station.
For example, 1 GB provides 128 MB for the server and 128 MB for 7 sessions. 2 GB provides 128 MB for the server and 128 MB for 15 sessions.
Server speed is also important. A faster chip will provide better performance than a slower chip. Using a dual processor will also improve performance.
We often think of servers as a specialty style of hardware: rack mounted, RAID hard drives, dual or quad processors, and redundant power supplies. This style of hardware is ideally suited to the demands of server computing, but is not the defining criteria. What creates a server is the operating system. Server software can effectively run on a variety of hardware configurations. While the modern rack-mounted server is ideally suited to the task, desktop workstation hardware can also be used to run server software.
See Microsoft Terminal Server Installation for details.
ACP Enabled Thin Clients connect to the terminal server using TCP/IP. All current models use 10-based T/ 100-based T Ethernet. Fiber-optics can be used for the network backbone.
Dual Network Card: A common practice is to use two network cards in the terminal servers. One card can attach to the corporate network to allow communication with the entire plant. A second network card is used for the thin clients, PLCs and process control instruments. This eliminates traffic on the thin client subnet, and allows DHCP to be set up for the thin clients that doesn't interfere with the corporate network.
ThinManager Ready thin clients are ACP enabled thin clients. These are PCs that run without a hard drive and a configurable and maintainable operating system. The ThinManager Ready label on the hardware shows that it is ready to connect to ThinManager.

ThinManager Ready Logo
See here for details on hardware.
ACP Enabled Thin Clients require a server running Microsoft Windows 200 Server or Microsoft Windows 2003 Server with Terminal Services enabled. These allow terminals to login to the terminal server and run a complete Windows session on the server that is distinct and separate from the other sessions.
Microsoft requires that each terminal session has a Microsoft Terminal Services Client Access License (TS CAL).
See Microsoft Licensing for details.
The Client Communication Protocol provides the communication between the thin clients and the terminals. ThinManager supports both the default RDP (Remote Desktop Protocol) from Microsoft, and the ICA (Independent computer Architecture) from Citrix. The ThinManager Terminal Configuration Wizard allows either protocol to be selected for each terminal.
In the past ThinManager came bundled with a lite version of the ICA protocol called Citrix Device Services. Citrix stopped support of this version when Windows 2003 Server was released so ThinManager uses RDP as the default. ThinManager Ready thin clients can still connect to established Citrix Device Services terminal servers, but no new ones can be licensed.
ThinManager is an administrative user interface that controls, configures, and organizes the ACP Enabled thin clients. ThinManager is the visible control panel that works in conjunction with an invisible service named ThinServer.
The ThinManager interface has a control panel with a tree-view pane and a details pane. The tree-view pane provides "at-a-glance" management by icon color to show the on/off status of the terminal.
Selecting a terminal icon or group icon in the tree-view pane will display the configuration parameters of the terminal or group in the details pane. This provides quick access to configuration information.
When a terminal is added to a Group, it inherits the configuration of the group.
When a new thin client is added to the system, the ThinManager will prompt for the configuration of the new terminal. The terminal can be easily configured by either:
The configuration parameters include:
Use of modules speed the terminal boot process because the terminal will load only the code from the modules that are specified. The modules include:
ACP ThinManager has failover capabilities. If one or more terminal servers are used, ACP ThinManager can be configured so that if one server fails, the terminals will quickly connect to a server that is designated as a secondary server.
Select ThinManager Installation or ThinManager Licensing for details.
Before establishing the ACP thin client environment you need to determine the following:
See Quick Setup Steps and Setup Checklist for details.
(Updated 9/20/2006)