In , a thin client, sometimes called slim client or lean client, is a simple (low-performance) computer that has been optimized for Remote desktop with a server-based computing environment. They are sometimes known as network computers, or in their simplest form as zero clients. The server does most of the work, which can include launching software programs, performing , and Data storage. This contrasts with a rich client or a conventional personal computer; the former is also intended for working in a client–server model but has significant local processing power, while the latter aims to perform its function mostly locally.
Thin clients occur as components of a broader computing infrastructure, where many clients share their computations with a server or server farm. The server-side infrastructure uses cloud computing software such as application virtualization, hosted shared desktop (HSD) or desktop virtualization (VDI). This combination forms what is known as a cloud-based system, where desktop resources are centralized at one or more . The benefits of centralization are hardware resource optimization, reduced software maintenance, and improved security.
- Example of hardware resource optimization: Cabling, bussing and I/O can be minimized while idle memory and processing power can be applied to user sessions that most need it.
- Example of reduced software maintenance: Software patching and operating system (OS) migrations can be applied, tested and activated for all users in one instance to accelerate roll-out and improve administrative efficiency.
- Example of improved security: Software assets are centralized and easily fire-walled, monitored and protected. Sensitive data is uncompromised in cases of desktop loss or theft.
Thin client hardware generally supports common , such as keyboards, mice, Computer monitor, jacks for sound peripherals, and open ports for USB devices (e.g., printer, flash drive, webcam). Some thin clients include (Legacy port) Serial port or to support older devices, such as receipt printers, scales or time clocks. Thin client software typically consists of a graphical user interface (GUI), cloud access agents (e.g., RDP, ICA, PCoIP), a local web browser, terminal emulators (in some cases), and a basic set of local Utility software.
Characteristics
Architecture
The simplicity of thin client hardware and software results in a very low total cost of ownership, but some of these initial savings can be offset by the need for a more robust cloud infrastructure required on the server side.
An alternative to traditional server deployment which spreads out infrastructure costs over time is a cloud-based subscription model known as desktop as a service, which allows IT organizations to outsource the cloud infrastructure to a third party.
Simplicity
Hardware
Graphics
Some of the more graphically intense use cases remain a challenge for thin clients. These use cases might include applications like photo editors, 3D drawing programs, and animation tools. This can be addressed at the host server using dedicated GPU cards, allocation of VGPU (virtual GPU), workstation cards, and hardware acceleration cards. These solutions allow IT administrators to provide power-user performance where it is needed to a relatively generic endpoint device such as a thin client.
Limitations
While running local productivity applications goes beyond the normal scope of a thin client, it is sometimes needed in rare use cases. License restrictions that apply to thin clients can sometimes prevent them from supporting these applications. Local storage constraints may also limit the space required to install large applications or application suites.
It is also important to acknowledge that network bandwidth and performance is more critical in any type of cloud-based computing model. IT organizations must ensure that their network can accommodate the number of users that they need to serve. If demand for bandwidth exceeds network limits, it could result in a major loss of end user productivity.
A similar risk exists inside the data center. Servers must be sized correctly in order to deliver adequate performance to end users. In a cloud-based computing model, the servers can also represent a single point of failure risk. If a server fails, end users lose access to all of the resources supported by that server. This risk can be mitigated by building redundancies, fail-over processes, backups, and load balancing utilities into the system. Redundancy provides reliable host availability but it can add cost to smaller user populations that lack scale.
Providers
History
Windows NT became capable of multi-user operations primarily through the efforts of Citrix Systems, which repackaged Windows NT 3.51 as the multi-user operating system WinFrame in 1995, launched in coordination with Wyse Technology's Winterm thin client. Microsoft licensed this technology back from Citrix and implemented it into Windows NT 4.0 Terminal Server Edition, under a project codenamed "Hydra". Windows NT then became the basis of Windows 2000 and Windows XP. , Microsoft Windows systems support graphical terminals via the Remote Desktop Services component. The Wyse Winterm was the first Windows-display-focused thin client (AKA Windows Terminal) to access this environment.
The term thin client was coined in 1993(thin client term was coined 1993) by Tim Negris, VP of Server Marketing at Oracle Corporation, while working with company founder Larry Ellison on the launch of Oracle database. At the time, Oracle wished to differentiate their server-oriented software from Microsoft's desktop-oriented products. Ellison subsequently popularized Negris' buzzword with frequent use in his speeches and interviews about Oracle products. Ellison would go on to be a founding board member of thin client maker Network Computer, Inc (NCI), later renamed Liberate.
The term stuck for several reasons. The earlier term "graphical terminal" had been chosen to distinguish such terminals from text-based terminals, and thus put the emphasis heavily on graphics – which became obsolete as a distinguishing characteristic in the 1990s as text-only physical terminals themselves became obsolete, and text-only computer systems (a few of which existed in the 1980s) were no longer manufactured. The term "thin client" also conveys better what was then viewed as the fundamental difference: thin clients can be designed with less expensive hardware, because they have reduced computational workloads.
By the 2010s, thin clients were not the only desktop devices for general purpose computing that were "thin" – in the sense of having a small form factor and being relatively inexpensive. The nettop form factor for desktop PCs was introduced, and nettops could run full feature Windows or Linux; Tablet computer, tablet-laptop hybrids had also entered the market. However, while there was now little size difference, thin clients retained some key advantages over these competitors, such as not needing a local drive. However, "thin client" can be a misnomer for slim form-factor computers using flash memory such as compactflash, SD card, or permanent flash memory as a hard disk substitute. In 2013, a Citrix employee experimented with a Raspberry Pi as a thin client. Since then, several manufacturers have introduced their version of Raspberry Pi thin clients.
See also
Other client types
- Dumb terminal: Like thin clients, but have zero local processing power and support no peripherals
- Rich client: Have ample local processing power, although they are heavily network-dependent
- Diskless node: It has no local storage (e.g. no hard disk drives) but may have anything else that a full workstation has
Related concepts
- Centralized computing
- Desktop virtualization
- Multiseat configuration
- Time-sharing
- Hosted desktop
Others
- AOL TV
- Blade PC
- Sun Ray
- Network Computer: a diskless desktop computer device made by the Oracle Corporation from about 1996 to 2000
External links
|
|
