A major advantage of server-based computing technology is that the type of client platform and device that determines which applications you can use is removed from the equation. While good from a business perspective, it can have the negative effect of making your technology decisions difficult. It was easy when applications only worked in Windows environments. If a user needed to use the application, they needed a computer running Windows—period.
Now that Terminal Server has come along, users can access Windows applications from virtually any platform and device. Each platform and device combination offers slightly different options for you (the administrator) and your users.
In order to evaluate which types of client devices are best suited to your environment, you must answer a series of questions. These questions can be grouped within five categories:
Technology management issues.
Environment and facilities aspects.
Do you need client devices that pull all configuration parameters from a central area and thus do not require local configuration? If you have devices that require local configuration, do you have the skill, software, and ability to automatically script and push out this configuration, or will you need to visit each client device manually?
If each client device contains custom data and configuration information for its user, then IT support personnel could potentially spend significant amounts of time troubleshooting and hunting down problems within each client device. Traditionally this has been the case with Windows-based PC workstations.
In the thin-client world, troubleshooting doesn't require that kind of time. Many companies deploy generic client devices to end users with all users' applications executing on Terminal Servers and their data stored on network drives. If a client device were to stop working properly, the IT staff doesn't have to waste valuable time troubleshooting it. They can pull it out and replace it with a new device.
If your user environment is located at a main corporate campus or if you have local IT department staff, it's possible to use client devices that require some manual configuration or expertise to install. However, lacking an IT staff at the users' site, you must use client devices that a non-technical person can troubleshoot; usually, thin client devices. If one stops working, a non-technical person can go to the closet, get a new one, and plug it in in place of the broken one. The cables are color-coded, and all configuration information and application information is either preset or downloaded from a server.
Do your users respect the IT department or are they hostile? (Believe it or not, there are some environments in which the users actually respect IT.) In the presence of mutual respect, it will be easier to introduce new technologies and devices to the end users. If the relationship is strained, every detail of the IT department's technology decisions will be scrutinized. Any aspect of the new technology that the users feel is lacking could cause a user revolt.
In traditional environments where full PC workstations reside on each user's desk, many users have become accustomed to "personalizing" their computers, as seen in custom desktop themes, screen savers, wallpapers with pictures of users' kids, and animated dinosaur mouse pointers.
You might choose to replace your users' customizable PCs with thin client devices that are managed as generic company assets and can be replaced if broken, much like the telephone.
Though these thin client devices provide a 100% identical look and feel of business applications, users can be put off if they were to lose some "freedoms," such as the ability to customize settings and use floppy disks.
Will your users be able to adapt to new solutions or technologies, or will they call the helpdesk every day for a month? Even worse, are they too smart (or crafty)? Will they try to break or get around whatever procedures are put in place? You should spend time trying to understand what your users' true needs are. Keep in mind that some users are never happy. No matter what you do, they will always want more.
Most users tend to meddle with whatever configuration settings and options they can find on their client computers. When considering client devices, it's important to assess how easily they can be "locked-down," preventing users from breaking them.
Will end users need secure access over the network, or will they need secure authentication, such as smart cards or biometric authentication? How about the client devices themselves? If they are located somewhere in which theft is a problem, thin client devices are preferable to PC workstations since they are worthless outside of an office environment (unless the thieves set up a Terminal Server in their hideout). If they are stolen, thin client devices are cheaper to replace.
Sometimes Terminal Server is deployed in environments that haven't updated desktop technology for many years, so it's easy to justify the cost of new client devices that are purchased as the Terminal Server applications are rolled out.
More common, though, are the environments that lease or refresh their desktop technology every few years. Even if the IT department decides that thin client devices are the cheapest, easiest, and coolest client devices they could use, they may not be a possibility if the end user departments "just got new PCs last year, we're not pulling them out now."
If politics force you to use existing client devices, then your client device selection process shouldn't take long.
Often end user departments pay for their own client devices. In these cases, you need to know whether they typically purchase what the IT department recommends or if they purchase whatever they want (usually based on cheapest price). If they go by IT recommendations, are there particular vendors that must be used or price caps that must be observed?
Of course, even if the IT department pays for the end user devices, these same political and pricing issues may still apply.
If the end user environment is harsh or dirty, client machines may break more often, requiring ones that are inexpensive and easy to replace. If the client environment has sanitary requirements, as in hospitals, the client devices might need to be hermetically sealed or have the ability to be easily disinfected.
Many traditional computers require 200 to 300 watts to operate, while many thin client devices operate on 25 watts or less. When you consider that these devices are used for at least 2000 hours per year, and with energy prices always increasing, the power cost savings can be tremendous, even with a few hundred users.
If only Terminal Server applications will be used, then any client devices will work (thin client, Windows CE, full PC, etc.). But, if users will ever need to access an application that is not delivered via the Terminal Server, they will need client devices that support other applications. Interestingly, this issue drives the balance between the number of applications in the Terminal Services environment and the complexities and expenses associated with different client devices.
In addition to the types of applications that are used, you must evaluate how many applications a user will need.
If the user is using less than five applications every day (word processor, email, web, and a line of business application), then it makes it easy for you to recommend thin client devices. However, the more applications a user requires, the tougher it becomes to use thin client devices. You might also need to consider other factors, such as the length of application usage. How many times is the user switching between applications per day?
Do the users have applications with high graphics requirements? Some thin client devices have better graphics performance than others, evident in high resolutions and color depth.
Do the users need audio support on their client devices? Remember that although audio support might not be perceived as necessary by the IT department, the users may be very upset if they "lose" sound when moving to a Terminal Server-based solution.
If users need to be able to move around while using their Terminal Server applications, is this movement confined to one area or one building, or will they need to access their applications from anywhere in the country?
How will mobile devices be used? The requirements of users that need access primarily from one location with the ability to roam are different from those of users that primarily need to roam. Battery life is also a factor.
Some environments may require specific peripherals, such as bar code readers or scanners. If this is the case in your environment then you will need to evaluate whether applications will support the barcode readers through thin client devices and Terminal Server sessions or if the applications will need to be installed locally on traditional PCs.
If users will be traveling with their client devices, such as laptops, then you must make provisions for them to have access to applications when they are offline. You won't be able to use Terminal Server, at least while the laptop users are not connected.