Sun Ray thin client

Federal Computer Week (US)

The Sun Ray thin client harkens back to the old days of mainframe/terminal computing, in which the client is merely an entry point to the applications that run on the server. Indeed, the Sun Ray includes only a video card and a network interface in the terminal. The software on the host Unix system handles all of the processing for the user session, and only pixel changes are sent over the wire to the Sun Ray.

Now Sun Microsystems Inc. has bolstered its Sun Ray thin client product line with two all-in-one terminals, the Sun Ray 100, which packages the Sun Ray thin-client functionality in an iMac-like CRT monitor, and the Sun Ray 150, which comes with a flat-panel version.

These thin-client units have some obvious advantages, not the least of which is their low price. The basic Sun Ray, the Sun Ray 1, is now offered by Sun at $590 individually. The Sun Ray 1 requires a separately purchased monitor. Because they are fully self-contained, the Sun Ray 100 and 150 offer complete solutions at $960 and $2070 respectively.

The Sun Ray also delivers completely centralized computing resources with a variety of options for access. In situations where there is little or no existing infrastructure – and, thus, no need to port applications and network services to a new platform, the rock-bottom price point of the Sun Ray (compared to desktop PCs) coupled with the ease of management of a central host make the Sun Ray a cost-effective solution.

By employing a cross-platform ap-plication server such as Citrix Systems Inc.’s MetaFrame, the Sun Ray can run Microsoft Corp.’s Windows applications from a Windows NT or Windows 2000 server on the Sun Ray desk-top. This means users can deploy Sun Ray in environments where they need access to Unix and Windows systems.

For applications that are exclusively browser-based, the Sun Ray is an excellent replacement for desktop PCs. The simple Sun Ray hardware is less expensive and less complex than a traditional PC. The centralized nature of the Sun Ray architecture can simplify the management of your computing environment.

Finally, the portable nature of the Sun Ray can make it ideal for educational or other environments, such as computer laboratories, where users may use one system one time and a completely different system another time.

I took a look at one of each of the Sun Ray systems (the 1, 100 and 150) attached to a Sun Enterprise 250 server with twin 400MHz UltraSPARC processors and 2G of RAM. Sun claims that one CPU can support 25 to 50 Sun Ray users, with the exact number determined by how much each user accesses the server. Based on this claim, the system I tested should be able to support 50 to 100 users.

I didn’t uncover any performance issues during my testing. The Sun Ray boots up quickly and, even when running numerous applications on the different Sun Rays, performance was impressive.

Still, the Sun Rays require slightly unconventional network architecture, and tuning and maintaining it are critical to meeting performance requirements.

Sun intends for the Sun Ray clients to run on their own dedicated, switched, 100baseT network. It’s easy to see that by sending pixel changes over the wire, the Sun Ray systems will consume considerable network bandwidth. Sun has optimized the Sun Ray architecture to work on a network of Sun Ray systems. PCs doing other network tasks can make life difficult for these clients, according to Sun. This means that deploying Sun Rays into an existing PC-based infrastructure may require some upgrades or changes to your network architecture.

Deploying and tuning the Sun Ray network are facilitated by Sun’s quad 100-megabit Ethernet card, one of which came with the Enterprise 250 I used for testing. The quad Ethernet card provides a flexible network solution that minimizes the number of system slots consumed by network interface cards.

The Sun Ray clients use Dynamic Host Configuration Protocol to obtain an IP address and boot to a log-in screen quite quickly. After all, there aren’t any X servers or other software to start up on the client – only the video display.

There really isn’t any configuration to be done on the Sun Ray itself. Most of the settings are configured through shell scripts during software setup or through the Sun Ray’s browser-based administration tool, which is served up by the Sun Ray’s host system. The browser-based administration tools are generally strong, though I was disappointed to find that some settings still have to be written manually in configuration files.

One of the nice features of the Sun Ray is its support for smart cards, which can be set up in a variety of configurations. In its most basic configuration, you can log in to a Sun Ray terminal using a user name and password, assuming you have an account on the host system.

By adding a smart card to the mix, you can require the card to be inserted in the Sun Ray for the user to log in, or you can have a user’s session follow them wherever they go. Removing the smart card from the Sun Ray removes your session from the screen and puts up a fresh log-in screen. However, your session hasn’t gone away; it is still running on the host. Once you plug your smart card into another Sun Ray, you can restore your session as if you never logged out.

Of course, with folks leaving sessions running, it is important to ensure that resources on the host system are not drained. The current Sun Ray implementation includes some options for what to do with idle processes. More support in this area would be welcome.

The Sun Ray is a compelling solution. With the price points that the Sun Rays offer, and given the fact that the Sun Ray software can run on any Solaris 2.7 host, agencies can test a Sun Ray implementation quite inexpensively. If your agency or department is considering options for managed desktops, you would do well to take a look at the Sun Ray.

–Hammond is a freelance writer based in Denver. He can be reached at


Sun Ray 1, 100 and 150

Score: B+

Sun Microsystems Inc.


Remarks: With simple client hardware and centrally managed server software, the Sun Ray solution offers inexpensive desktops and simplified management. The low cost and relative ease of setting up a Sun Ray deployment make it a viable desktop replacement solution for many agencies.

Copyright 2000 Federal Computer Week (US), International Data Group Inc. All rights reserved.

Prices listed are in Cdn currency.