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Thin clients aren't the only endpoint devices that can run VDI sessions. Broaden your horizons and consider zero clients, tablet PCs and smart clients.
To help you determine which aveunue is best for your environment, let's review the pros and cons of the four major endpoints you can use for virtual desktop infrastructure (VDI):
Good ol' thin clients
A thin client can be thought of as a slimmed-down version of a PC. It has the same key components, such as a processor, storage, RAM and an operating system, but on a smaller scale and with less computing power. Thin clients are designed to be inexpensive VDI clients and therefore have only the processing capacity necessary to effectively present the user interface.
The operating system is typically Windows XP Embedded, because many users are already familiar with this OS, and some legacy apps may require it. Medical environments often use this OS. Other operating systems are also supported, such as Windows CE, Windows 7 Embedded, a flavor of Linux or the manufacturer's proprietary OS. The local OS is usually installed on a 1GB, 2 GB or 4 GB flash drive or on a solid-state drive.
- Expensive back end
- Limited peripheral support
- Higher level of IT skill needed to build and support back end
- Additional licensing may be required
- Limited support for advanced multimedia
Zero clients strip down
A zero client doesn't have any processing, drives or an embedded operating system. It is a small box that plugs into a power source and connects a keyboard, mouse and monitor for the end user. Some zero-client devices make a direct physical cable connection to their host systems and are truly "dumb" terminals.
Other zero clients include some networking smarts and can communicate over a standard Ethernet network to the host system. This scenario requires additional software to be integrated on the host system, and IT admins need to pay special attention to network requirements.
Some newer zero clients implement Power over Ethernet, which safely passes power and data over Ethernet cabling. This can eliminate the need for power outlets altogether. The term "zero client" sometimes get attached to products that should be called "thin clients," because they run a local OS or use software and/or remote protocols that can require software updates.
- Low-cost endpoints
- No embedded OS to update, maintain and secure
- Zero endpoint management and configuration
- Very low energy costs
- Lack of moving parts improves lifespan of the product
- Some zero clients cable directly to the host system and have distance and scalability limitations
- Network-based zero clients require a fast network connection with low latency and low packet loss and can consume considerable bandwidth
- Often use proprietary solutions and not industry-standard protocols
What about tablet PCs?
A tablet PC is a thin slate dominated by a touchscreen. It is extremely light, typically averaging less than 1.5 pounds, making it vastly portable. These endpoint devices run on a lightweight, touchscreen-focused operating system, such as Apple iOS, Google Android or Microsoft Windows 7 (Windows 8 is also optimized for tablet use). Tablet PCs offer programs and "apps" for interoffice and customer communication and organization. Typical apps include email, calendar, word processing and presentation.
- Less expensive than a typical desktop
- Mobility with wireless access and an optional data plan
- Lightweight, averaging less than 1.5 pounds.
- Long battery life, averaging eight to 10 hours
- More fragile than other devices
- Lack USB support
- Native email support
Bring your own device (BYOD) policies allow employees to use their own equipment to get their jobs done. BYOD endpoint devices may be home PCs and, increasingly, employee-owned mobile devices that include tablet PCs. Once applications and the desktop environment are virtualized and securely hosted, the VDI client itself becomes less and less important. IT can deploy, manage and support apps at the server, eliminating the need to upgrade current hardware just to run the latest software.
How smart are smart clients?
The term "smart client" can refer to a specially programmed device, but IT professionals typically use it to describe an application environment rather than physical endpoint devices. A smart client application does not require an installation, but is instead delivered over the Web and automatically updates without any user intervention.
Smart clients supposedly bridge the gap between Web and desktop applications. They are more robust than standard Web applications running on the functionality of HTTP. Smart clients provide the high performance of a desktop application without needing to run on a high-end desktop. Platforms that can be used for building smart-client applications include Flex, JavaFX, Silverlight and DataSnap.
- Use local resources
- Installation and updates are seamless
- Client device flexibility
- Limited applications available
- Code needs to be written
- More difficult to deploy