NTA Thin Client Terminals from $149

Devon IT Inc. has embedded an “optimized” version of Red Hat Linux in a line of low-cost thin-client terminals ranging from the entry-level Ntavo NTA 6010A priced at $149, to the $599 NTA 6015L that boasts an integrated 15-inch, 1024×668 TFT LCD screen. The company has avoided the common practice of maximizing features and charging high prices, in favor of offering the most “cost-effective thin-client alternative to desktop PCs,” it says.

According to the company, the low-end 6010A is powered by a Via Eden 4000 433 MHz processor. It comes equipped with 64MB of socketed DIMM DRAM and 64MB of CompactFlash memory, and a display controller that supports CRT and LCD monitors at up to 1280×1024 pixels in 24-bit color. Expansion ports include: three USB ports; serial, parallel, and PS/2 keyboard/mouse “legacy” ports; audio in/out ports; and a 10/100 Mbps Ethernet interface.

The NTA 6010A offers an “easy-to-use graphical user interface (GUI) based on [a] Windows XP theme,” according to Devon, and it comes with built-in support for RDP (remote desktop protocol), ICA, and X client protocols, enabling its use as a terminal running remotely served Windows, Linux, or UNIX software applications, whether on a LAN or over the Internet.

The device’s embedded software also includes QVW Windows Manager and the Mozilla Firefox Web browser, as well as a client-side version of the company’s ThinManage configuration software. Thanks to the presence of Firefox, the device can be used out-of-the-box as a Web appliance, according to Devon vice president of marketing Paul Mancini.

As noted, the NTA 6010A and its higher-priced siblings include USB ports as well as a single internal PCI slot, which can be used for system expansion. The internal PCI slot is typically used to add a WiFi wireless card, according to Mancini.

Users can also add external hard drives and CD-ROMs by means of the USB ports. Additionally, the device’s DRAM consists of a socketed DIMM module, and its Flash memory is implemented with a CompactFlash card, so it should be easy to upgrade the unit’s DRAM memory and Flash storage. It also seems likely that the CompactFlash memory card can be replaced with a CompactFlash “Microdrive” hard drive, or even a 2.5-inch, laptop-style hard drive.

To date, all of Devon’s products have been based on Linux, Mancini added. However, “we will be announcing a Windows XPe thin client terminal soon, based on customer demand,” he said.

At $149, the NTA 6010A appears to be one of the lowest priced Linux thin clients currently on the market. “We are not aware of any terminals at this price point,” said Mancini. “The specs on our 6010A terminals at $149 compare to Wyse and Neoware terminals that are nearly $400 (list price),” he added.

The NTA 6010A is currently available from Devon IT.

What Is Thin Client ?

A thin client is a computer (client) in client-server architecture networks which depends primarily on the central server for processing activities. The word “thin” refers to the small boot image which such clients typically require – perhaps no more than required to connect to a network and start up a dedicated web browser or “Remote Desktop” connection such as X11, Citrix ICA, Microsoft RDP or Nomachine NX.

 

In contrast, a thick or fat client does as much processing as possible and passes only data required for communications and archival storage to the server.

 

Introduction

 

n designing a client-server application, there is a decision to be made as to which parts of the task should be done on the client, and which on the server. This decision can crucially affect the cost of clients and servers, the robustness and security of the application as a whole, and the flexibility of the design to later modification or porting.

 

One design question is how application-specific the client software should be. Using standardized client software such as a Web browser or X11 display can save on development costs, since one does not need to develop a custom client—but one must accept the limitations of the standard client.

 

Depending on the outcome of these decisions we might say that we use either a thin client or a thick/fat client (or a mixture of both).

 

Definitions

 

A thin client is a network computer without a hard disk drive, which, in client/server applications, is designed to be especially small so that the bulk of the data processing occurs on the server

 

Application program

 

A thin client as an application program communicates with an application server and relies for most significant elements of its business logic on a separate piece of software, an application server, typically running on a host computer located nearby in a LAN or at a distance on a WAN or MAN.

 

A thin client does most of its processing on a central server with as little hardware and software as possible at the user’s location, and as much as possible at some centralized managed site.

 

The meaning of the words “significant elements”, “core function”, “most” and “as little” are arguable.

 

Other definitions of thin versus thick/fat client application program try to draw the line at whether the deployment of the application requires the installation of additional software at the user site or not. Unfortunately, this is also arguable, since e.g., a browser used for a client application might be part of one client platform, but not the other. So on one platform no additional software installation is required, while another client platform requires it. The only objective definition would seem to be whether the boot image that is normally used to start the user’s computer needs to be modified in any way before the client can be used: if not, then, the client is probably thin. Another criterion is related to the management of the thin client device or program. If it can be centrally managed, it is probably thin.

 

However, a great deal of software is today typically included in a base boot image, specifically to support various user applications, so that it need not be reinstalled on every computer. Often, a departmental boot image is prepared to include applications specific to a department.

 

User-interface device

 

A thin client as a device is designed to provide just those functions which are useful for user-interface programs. Often such devices do not include hard disk drives, which may become corrupted by the installation of misbehaved or incompatible software, but instead, in the interests of low maintenance cost and increased mean-time between failures (MTBF) the thin client device will use read-only storage such as a CD-ROM, Network Virtual Drive or flash memory.

 

Ideally the user will have only a screen, keyboard, a pointing device (if needed) and enough computer to handle display and communications. Companies that develop and market these devices include Wyse, Chip PC, Sun Microsystems, WML (UK), BOSaNOVA, and Hewlett-Packard.

 

Device for running a thin client application program

 

“Thin client” has also been used as a marketing term for computer appliances designed to run thin client software. Chip PC Xtreme PC, Chip PC Jack PC, X terminal, Wyse Winterm, Neoware Appliance, Clearcube or Web kiosk might be considered thin clients in this sense.

 

The latest concept in this genre is ‘Ultra Thin Client’ technology – which takes the ‘thin’ concept one step further by running the connection client software (Citrix, Windows Terminal Services, telnet etc) directly from the appliance’s hardware. This is a marked difference to legacy thin-client hardware architecture which ran an operating system, often Windows CE or Linux between the hardware and connection client software. There are many benefits in not requiring an operating system, lower cost, higher performance and non-vulnerablity to viruses.

 

Software thin client

 

Most thin clients are software-only however, and run on standard PC hardware. One example of this software-only thin client is PXES Universal Linux Thin Client and Pilotlinux. Knoppix is also actively pursuing this market, as is ThinStation. (See also Puppy Linux). An example on the Windows platform is the BeTwin program, which uses extra VGA/DVI graphics ports, or cards, in the host PC plus USB connected keyboards and mice to enable additional workstations.

 

Examples of thin client and thick client usage

 

The advocates of both architectures tend to have contentious relationships. In practice, there seems to be little to choose between the two approaches for many applications. A few situations may clearly call for one or the other. Distributed computing projects such as the SETI@home project (whose whole point is to pass off computationally intensive analysis to a large collection of remote computers) are applications that require thick clients. On the other hand multicasting entertainment or educational material to a number of clients might best be done with thin clients since exactly the same material is to be presented at each.

 

Some technologies such as Network Virtual Disks or Disk Drive Images are aimed to provide central management and security/reliability/affordability comparable to what is found in Thin Client devices: the OS that operates the client is stored on a shared virtual disk image (a disk image file) that is housed on a server in the clients’ LAN. This virtual disk drive is “write protected” and shared by several clients at the same time. The content of this virtual disk drive is streamed on demand to the clients. Yet, all the computing is done by the client itself. Instead of centralizing a complete computer (centralize the storage, CPU, memory, devices etc) this approach centralizes only the hard disk drives. Because the virtual disk drives can be shared and protected, the aim to reduce TCO is also achieved with this technology. This technology can be used to run typical Embedded Operating Systems such as Embedded Linux and Windows XP Embedded, but also to run desktop operating systems such as Microsoft Windows XP Pro, FreeBSD or Linux.

 

Organizations that develop and market Network Virtual Disks include Linux Terminal Server Project, IBM (iBoot technology) and Ardence. Network Block Device support is another kind of Network Virtual Disk embedded in Unix and Linux.

 

Advantages of thin clients

 

Obviously, boot image control is much simpler when only thin clients are used – typically a single boot image can accommodate a very wide range of user needs, and be managed centrally, resulting in:

 

1. Lower IT admin costs. Thin clients are managed almost entirely at the server. The hardware has fewer points of failure and the local environment is highly restricted (and often stateless), providing protection from malware.
2. Easier to secure. Thin clients can be designed so that no application data ever resides on the client (it is entirely rendered), centralizing malware protection.
3. Lower hardware costs. Thin client hardware is generally cheaper because it does not contain a disk, application memory, or a powerful processor. They also generally have a longer period before requiring an upgrade or becoming obsolete. The total hardware requirements for a thin client system (including both servers and clients) are usually much lower compared to a system with fat clients. One reason for this is that the hardware is better utilized. A CPU in a fat workstation is idle most of the time. With thin clients, memory can be shared. If several users are running the same application, it only needs to be loaded into RAM once with a central server. With fat clients, each workstation must have its own copy of the program in memory.
4. Lower Energy Consumption. Dedicated thin client hardware has much lower energy consumption than thick client PCs. This not only reduces energy costs but may mean that in some cases air-conditioning systems are not required or need not be upgraded which can be a significant cost saving and contribute to achieving energy saving targets.
5. Worthless to most thieves. Thin client hardware, whether dedicated or simply older hardware that has been repurposed via cascading, is useless outside a client-server environment. Burglars interested in computer equipment have a much harder time fencing thin client hardware (and it is less valuable).
6. Hostile Environments. Most devices have no moving parts so can be used in dusty environments without the worry of PC fans clogging up and overheating and burning out the PC.
7. Less network bandwidth. Since terminal servers typically reside on the same high-speed network backbone as file servers, most network traffic is confined to the server room. In a fat client environment if you open a 10MB document that’s 10MB transferred from the file server to your PC. When you save it that’s another 10MB from your PC to the server. When you print it the same happens again – another 10MB over the network to your file server and another 10MB back to the printer. This is highly inefficient. In a thin client environment only mouse movements, keystrokes and screen updates are transmitted from/to the end user. Over efficient protocols such as ICA or NX this can consume as little as 5Kbps bandwidth.

 

 

Advantages of thick clients

 

1.      Fewer server requirements. A thick client server does not require as high a level of performance as a thin client server (since the thick clients themselves do much of the application processing). This results in drastically cheaper servers.

2.      Better multimedia performance. Thick clients have advantages in multimedia-rich applications that would be bandwidth intensive if fully served. For example, thick clients are well suited for video gaming.

3.      More flexibility. On some operating systems (such as Microsoft Windows) software products are designed for personal computers that have their own local resources. Trying to run this software in a thin client environment can be difficult.

 

Advantages of Network Virtual Disks clients

 

Disadvantages of Network Virtual Disks clients

 

100Base-T LAN required. Because of the amount of data streamed to the clients, it is usually difficult to have a Network Virtual Disk client connected through a WAN link to the server that houses..

An Introduction to Terminal Services Remote Programs (Part 1)

When you think of a Terminal Services session, you probably think of a thin client environment in which all of a user’s applications run on a terminal server, and the user’s PC simply acts as a dumb terminal. Although this has traditionally been the case with the Windows Terminal Services, Windows Longhorn Server will offer a new type of Terminal Service session called Terminal Services Remote Programs. Longhorn Server will continue to offer the type of Terminal Server environment that you are already used to, but you will now have the option of using Terminal Services Remote Programs to create a sort of hybrid user environment in which some applications are installed locally and other applications transparently run on a terminal server. Applications running on a Terminal Server provide the illusion of running locally. In this article, I will introduce you to this new Terminal Service environment.

Why Use Remote Programs?

The first thing that you’re probably wondering about Terminal Services Remote Programs is why in the world you would ever want to use them? One possible reason for running Terminal Services Remote Programs is to be able to run an application on a client that would not normally support the application. The way that Terminal Services Remote Programs works, users may have no idea that an application isn’t being run locally.

Of course this still doesn’t answer the question of why you would want to use Terminal Services Remote Programs. Imagine a situation in which you need to deploy a new application, but the user’s workstations are outdated and incapable of running the application. In such a situation, you would normally have two options. One option would be to purchase new hardware for the users, thus allowing them to run the application. The other option would be to deploy a Terminal Services environment and have the users work through a Terminal Services session rather than working off of the computer locally.

There are several problems with switching the users over to a Terminal Services environment. For starters, the organization would have the expense of purchasing a server that can be used to host the Terminal Services, and the expense of the associated licenses. There is also the issue of training the administrative staff on how to manage a Terminal Services environment. Another possible issue is the amount of time that it would take to deploy a full blown Terminal Services environment. Depending on the organization’s business need, and how critical the new application is, waiting for a Terminal Services deployment to be completed might not be an option.

Purchasing new computers for the users is not a perfect solution either. The most obvious issue is the cost of the new computers, which could be significant depending on how many users need new hardware. Another possible issue is the amount of time that it would take the administrative staff to configure the new computers before they are ready to be used.

Using Terminal Services Remote Programs won’t solve all of these problems, but in a situation like this it might be the best solution. Like any Terminal Services environment, you will need a server to host the Terminal Services sessions. However, depending on your organization’s needs, using the Terminal Services to host remote programs probably isn’t going to be nearly as complicated as running a full blown Terminal Services environment.

In a situation like this, you would still have the cost of a server that could be used to host the remote programs, and of course you would need to purchase the necessary licenses. However, depending on how many users have obsolete computers, this might be cheaper than trying to replace a bunch of desktops. Furthermore, using a terminal server to host remote programs should represent less of a learning curve for both the users and the administrative staff than switching to a full blown Terminal Service environment.

A completely different benefit to using Terminal Services Remote Programs is that you can provide access to remote programs over the Internet. The original intention of this feature was so that mobile users could access their applications from anywhere, so long as they have an Internet connection Longhorn server contains a new component called a Terminal Service Gateway, which allows access to either remote programs or to a full-blown Terminal Service session over the Internet (I have already written a series of articles on the Terminal Service Gateway). According to a friend at Microsoft, it is theoretically possible to build your own website, and host an application within it using this technology.