• Thin Client Technology in Detail
Thin–clients are inexpensive computers or terminals that are fed data (and applications) from centralized Terminal Servers. The basic philosophy driving thin-client applications is to put the enterprise computing power onto centralized terminal servers, data storage and applications, and provide users with an inexpensive "client" device.
The thin client connects to the Terminal Server through the network to run applications, access files, print, and perform services available to ordinary computers. The advantages are many: lower technology costs, reliable computing, easy-to-use devices, low maintenance needs, and secure data.
• The four major components of thin clients are:
• The Network Infrastructure
• Thin-Client enabling Software
• The Application Server- Terminal Server
• The Thin-Client devices - Including : monitor, keyboard & mouse
• The Network Infrastructure
The network infrastructure is the pipeline between the server and the client is the most critical element of the thin-client environment.
• The Application Server- Terminal Server
The application server requires the following: Windows 2000 Terminal Services, Windows 2003 Terminal Services, and/or Citrix® Presentation® server, using the thin-client protocols based on Microsoft's Remote Desktop Protocol or Citrix's Independent Computing Architecture (ICA®). Citrix also offers the Resource Management Services utility to help size, audit, maintain and track usage of the servers).
The application server may work with other Terminal Servers, networked together to form a server farm. A server farm can balance the load of users and resources across two or more servers to enhance performance and up time. The server farm is connected to other servers on the network. These additional servers, used for data storage, web hosting, e-mail, and other services, should be located as close to the application server as possible to reduce network traffic and enhance performance.
The Terminal Servers will be used to host the user's desktop applications. Most productivity software will run on Windows Terminal Servers.
Software vendors should be contacted to ensure specific applications are supported in a Terminal Services environment.
• The Thin-Client devices
Any user device connected to a Terminal Server is a called a "thin client".
Thin clients connect to the Terminal Server via the thin-client protocols like Microsoft RDP or Citrix ICA clients.
There are NO applications installed on the thin client device. Instead the business applications are deployed on the Terminal Servers and accessed by the thin clients over the network. Only screen changes, keystrokes and mouse clicks travel across the network.
Typically, a single Terminal Server can handle concurrently around 100 client connections. This depends on the number of simultaneous applications being used and how they are used. The requirement on the client side is very low, and old PC or dedicated terminal device, or “thin client” will be enough for day to day tasks.
Thin Client technology is suitable for any business, where users work on non-graphically intensive applications such as data entry, emails, word processor, spreadsheets or even in-house custom applications.
Adopting a thin-client environment is not complicated or costly. The Terminal Server can be easily deployed into your existing network infrastructure and will be used to host the user’s application sets. Existing PCs can be converted to become a thin-client PC.
To experience the true benefits of a thin-client/server-based computing model, one should consider using the wide range of thin-client devices over the expensive and complicated traditional PCs, which require extensive management and support.
• Comparison between thin clients capabilities with the traditional infrastructure in terms of:
• More Affordability – Thin Clients are more cost effective than the typical business PC, especially in regards to overall Total Cost of Ownership (TCO) and Return On Investments (ROI ) . There is no need to deploy and support applications locally on the Thin Client devices.
• Greater Performance and Efficiency – Thin Client technology deliver better performance, low bandwidth requirements and a tight integration with the Microsoft Windows operating system.
• Synchronization - centralized control on resources utilization, protection, and remote upgrade from the servers)
• Better Security – Thin client devices are virtually immune from virus infection since there are no local devices like hard disk, CD, or floppy drive. There will be no threat of contamination or security leaks as long as the Terminal Server itself is well updated with the latest anti-virus protection and security updates.
• Central Storage – IT organization will be able to make use of central data storage to store users data. With no local storage capability on thin clients, this will make your network secure, safe from intruders and easier backup strategy for data/documents.
• Easier Maintenance - if the thin client breaks down, a simple replacement of the same device will do. All user data and applications are still made available on the Terminal Server and central storage. There is no risk to lost of data/applications.
• Reliability - There are no moving parts in a thin client device. No noisy fans or no local drives that require maintenance. Virtually maintenance free.
• Central Administration and Manageability – IT support staff do not need to travel to each individual user’s desk to perform application deployment and maintenance (Eg. applying security patches, software upgrade or basic OS support). This allow IT organization to have a better IT support team working from the back end to provide centralized support.
• Upgrade path – Through a centralized Terminal Server model running applications centrally and not on the desktop, application performance can be upgraded in the future by upgrading servers, without ever touching the users desktops.
