Technology of the Month

Looking around University Relations and Admissions or on the desks of student workers in Student Activities and Residential Life, one sees the desktop replaced with a small, lightweight thin client. Computing veterans recall the days of “dumb” terminals and ponder the idea that technology has come full circle.  However, many users are confused by this new trend. Indeed, thin clients have a bad reputation in various corners on campus.  The goal of this article is to clarify misconceptions, and, hopefully, remove any apprehension should one find itself on your desk.

What is a Thin Client?

Wikipedia’s definition is rather technical: A client computer which… depends primarily on the central server for processing activities, and mainly focuses on conveying input and output between the user and the remote server.

Simply put – the user’s desktop environment – wallpaper, preferences, shortcuts – all reside on a central server that is hosting numerous desktop machines.  Those servers are hosting virtualized desktops.  There are applications designed to maximize performance of hardware to allow those servers to host many instances of a computer on a single machine.  Processing and memory are all distributed and used in an efficient manner to give each virtual computer what it needs at any given moment.  At Wesleyan, we have been working with virtual technologies for over three years.  Virtualized servers are commonplace and allow us to minimize hardware costs by having a few powerful machines host multiple servers.

Only one year ago did we begin to look at this as an option for desktop computers. The replacement of desktops is laborious and expensive. In response to economic demands, we have lengthened the replacement cycle to 4 years.  Many administrative users have not had their machines replaced in longer than that. The prospect can be daunting for a user. Replicating the environment and data takes time.  Users don’t often have the time to give to that process and prefer to wear their machine out before having to go through the transition to a new one.  While desktop costs have come down considerably in recent years, there are still associated costs including electricity and proper hardware disposal.

Pilot Testing the Virtual Desktop

ITS began testing Virtual Desktop Infrastructure (VDI) to determine its feasibility for specific groups of end users.  Good candidates are users who use standard applications or web-based applications, don’t have intense graphic design needs, and don’t depend on a large number of external devices.

Initial results internally were promising enough that we developed a pilot group of users who had badly aging desktops.  Those users received thin clients in replacement. In a VDI environment, each user has his/her own virtual desktop. This machine looks and acts like a physical computer desktop. The user can perform all the same takes he/she did on the physical desktop including customizing wallpaper, creating shortcuts, and saving data locally to the C drive.   When powered on, the thin client immediately connects to this machine and the user sees the standard Windows login screen.  If there is any problem with the thin hardware itself, it can be swapped in minutes and setup to connect to the user’s desktop with almost no downtime.

In spite of the internal results, once the testing went into the pilot group, there were performance problems.  These problems were significant enough that we did not expand the pilot until we researched and ultimately addressed the underlying causes.  Our success in doing so has afforded us a more solid understanding of the VDI environment. Consequently, we focused our effort on building a more robust infrastructure that can sustain expansion.

Lab and Common Area Connections

Another common application for thin clients is in labs or common areas where computers are available for very limited applications. In this case, a user will login to a Terminal Server session with access to applications such as email, web browsing, or Microsoft Office.  This is a good solution where multiple users will be logging into a machine and will not be saving data locally.  This differs from the Virtual Desktop described above because users do not have flexibility over their desktop environment.  There is limited access to a pre-defined set of programs.  Individual users cannot add or change the configuration.  Examples of this include McNair lab, Career Resource Center, email kiosks in ST Lab and PAC lab, and various student employee work areas on the campus.  This is a cost effective way to provide all the function necessary without older hardware and slower boot times.

Virtual Desktop Fact or Fiction

A thin client is a watered down version of a computer and doesn’t do all the things my old computer can do. – Fiction

The thin client connects to a virtual computer with a full installation of Windows that is the same as one installed on physical hardware.  Thin clients can support USB devices, printers, and even dual monitors.

ITS can see what I am doing while I am working on my computer. – Fiction

ITS staff cannot see what a user is doing any more than on a physical machine.  What ITS can see are performance issues on the virtual computer (memory or processor problems) and this allows us to respond much more quickly to potential issues that may interfere with the user.

Thin clients rely completely on the network. – Fact

Thin clients connect to virtual computers (or Terminal Servers) that reside in the data center.  They depend entirely on network connections.  Wesleyan enjoys a high availability network and downtimes are rare.  Since so many services are now delivered via web applications and other central services, network downtime affects both thin client users and those on physical machines alike.

If I have trouble with my thin client, there is nothing that can be done to make it better. – Fiction

Not only are there several configuration options, making virtual hardware changes is much easier than making physical ones.  Additional memory and processing can be added to a virtual computer rather easily.  At times, simple configurations within Windows will resolve issues in the same way it does on a physical machine.

In Closing…

We now have 27 virtual desktops throughout campus in both academic and administrative offices.  An additional 19 are in labs and kiosks.  While certainly not all users are candidates for this technology, it is working well where feasible and is an environmentally friendly solution with the potential to have long-term savings without sacrificing productivity.