The University of Toledo VLab
Another Piece of the Distance Education Puzzle
Berhane Teclehaimanot, Ph.D.
Department of Curriculum & Instruction
University of Toledo
United States
berhane.teclehaimanot@utoledo.edu
Joshua Spencer
Systems Engineer - Desktop Specialist
VMware, Inc.
United States
spencerj@vmware.com
Abstract
In today’s increasingly technological world, students are requiring more and more specialized computer
software to complete their studies and to obtain real world, hands-on experience. While this is a challenge for oncampus, traditional computer labs, it is even more difficult for distance education. The University of Toledo has
built VLab, a collection of highly customized virtual machines available to students around the clock, from
anywhere in the world.
Introduction
The term “distance education” often provokes thoughts of content delivery, such as text, video and audio
materials, to students at a remote location. Technologies such as e-mail, message boards, wikis and content
management systems are enabling educators and learners to share information more rapidly than using traditional
means such as correspondence. These technologies are all vital to educators in today’s high speed, competitive and
“global” world. Yet, there are additional aspects of distance education that these technologies simply do not address.
Consider the following excerpt from Wikipedia on the definition of distance learning:
Distance education, or distance learning, is a field of education that focuses on the pedagogy, technology, and
instructional system designs that aim to deliver education to students who are not physically "on site" in a
traditional classroom or campus. It has been described as "a process to create and provide access to learning when
the source of information and the learners are separated by time and distance, or both." In other words, distance
learning is the process of creating an educational experience of equal qualitative value for the learner to best suit
their needs outside the classroom. Distance education courses that require a physical on-site presence for any
reason including the taking of examinations is considered to be a hybrid or blended course of study, (Honeyman and
Miller, 1993).”
With this definition in mind, consider for a moment the tools students require to be successful in their
“educational experience”. Surely, regardless the field of study, most students will require the use of computers and,
more specifically, application software. At the University of Toledo, students rely on Maple for learning
mathematics, SAS and SPSS to analyze statistics, ArcGIS when studying geography, Microsoft Office for a variety
of purposes; and the list goes on and on. A typical university today might utilize dozens or even hundreds of
applications, many of which are highly specialized for specific fields of study, and expect students to demonstrate
some level of competency in using these tools. When we consider this aspect of the educational experience, we find
a challenge in providing effective distance education. If what we are trying to deliver to students is not simply
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content, but content coupled with the hands-on application using computer software, how do we do it? This question
is at the heart of this paper.
Traditionally we’ve had two options to address this issue: The first is to have students purchase the
software and install it on their own personal computers. The challenge with this method is that software is often
prohibitively expensive and might serve little purpose to a student once a course is complete. In addition, there will
undoubtedly be technical issues with system requirements and configuration that will affect the learning experience.
The second option is to provide content remotely and require students to come on-site to use a computer lab. When
we consider the definition of distance learning above, this option really shifts us away from distance learning to a
hybrid or blended model. In this paper we are proposing a third option, one that attempts to address the
shortcomings of the others, and provide a solution for this increasingly important component to distance education.
The University of Toledo
The University of Toledo consists of more than 20,000 students studying across multiple disciplines as well
as a 300-bed teaching hospital. To address the needs discussed in the last section, we’ve essentially built a private
cloud using an assortment of VMware technologies. This will be discussed further in the following section titled
“Technology”. We call our cloud “VLab” (http://www.utoledo.edu/it/vlab), and it is essentially a collection of
virtual machines tailored to the specific configurations of each of our colleges. The primary goal of VLab is to tear
down the time restrictions and physical boundaries of existing physical computer labs. This collection of virtual lab
computers can be accessed via the internet from anywhere in the world, around the clock, using a variety of endpoint devices such as Microsoft Windows PCs, Macs, thin clients, and mobile phones. Once connected through a
secure, encrypted tunnel, students are presented with their own virtual machine, fully configured with the universityowned software they need to be successful. Students taking DL courses are now able to obtain media from
Blackboard, our content management system, and then complete assignments requiring the use of specialized
applications using a virtual lab; all without setting foot on campus.
Today, we have approximately 1,000 virtual machines running nearly three dozen unique configurations for
individual colleges and specific courses. While remote access for students to our VLab has been the primary focus,
we’ve found a variety of other uses for this technology. Our dormitory lab computers, for example, have all been
replaced with Wyse thin client devices which provide access to the VLab virtual machines. This configuration
provides our students with a unified computing experience whether they’re on or off campus. It has also saved
individual departments on hardware acquisition and support costs, in addition to reducing energy consumption by
approximately 50% (Coyne, 2008) in these areas. A similar configuration is being used to deliver a more stable,
secure computing environment for nearly half of the UT medical center hospital. At the time of this writing there are
more than 600 thin client devices throughout the UT enterprise that are being used to connect to the private cloud
infrastructure.
Technology
Private Cloud
The term “private cloud” has been defined several ways. Consider the following examples:
“Cloud computing is Internet-based computing, whereby shared resources, software, and information are provided
to computers and other devices on demand, like the electricity grid (Wikimedia, 2010).”
“Private cloud (also called internal cloud or corporate cloud) is a marketing term for a proprietary computing
architecture that provides hosted services to a limited number of people behind a firewall (TechTarget, 2009).”
VLab is all of this. As you’ll see in more detail below, there is a great deal of technology, both hardware
and software, driving the virtual lab environment. But none of this is seen by student. They simply browse to a web
page, begin accessing compute resources as needed, and then close the page when they’re done, freeing up those
resources for the next person.
Virtual Machine
Before we go any further it is important to understand what a virtual machine is and how it differs from
traditional computers. Wikipedia defines virtual machines as either system virtual machines or process virtual
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machines (Wikimedia Foundations, Inc., 2010). In this document I will only be discussing system virtual machines
which, from this point forward, will be referred to as either “virtual machines” or simply “VMs”. To understand
what virtual machines are, let’s first take a brief look at how traditional, physical computers work.
There are two primary components to a computer: hardware and software. Hardware is anything that you
can touch such as the, keyboard, mouse, or hard drive. Software refers to any program that makes the computer do
something. Today, most computers are first loaded with operating system software such as Microsoft Windows or
Apple OS X. The operating system controls interaction between the various hardware components (such as a video
card and memory) and applications that are installed (such as a word processor or statistical package). Below is a
simple visual showing the relationship between hardware, operating system software, and application software.
Figure 1 - Logical layers of a traditional computer
With traditional computers, we see one physical machine (hardware) running one operating system and one
or more applications. With a virtual machine however, we separate the hardware, add a virtualization layer (also
known as a hypervisor) and gain the ability to run multiple operating system instances on a single piece of hardware.
We are effectively turning one physical machine in to several computers. In the virtualization world, the new model
looks like this:
Now that we’ve established our definition of a virtual machine, let’s look at some of the technology we use
to build and manage them for VLab.
VMware View
VMware View is at the core of VLab. This product is used for provisioning, managing, and brokering
virtual machines. The importance of these concepts is described below. View has a significant advantage over
competing products such as Microsoft Terminal Services and Citrix because of its unique approach to virtualization.
Rather than taking a single operating system and application configuration, slicing it up, and sharing
“sessions” between multiple users, View gives each user his/her own virtual machine. In fact, it presents the ability
to provide a brand new virtual machine to each user every time they access the virtual lab. This is a fully automated
process, relieving pressure from the IT support staff. This configuration is one we rely on heavily in order to ensure
the best possible experience for our students.
Each virtual machine is complete with an operating system, a set of applications, and a custom
configuration to match the needs of the college or specific course. The hardware (processor, memory, and storage)
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resources are shared between active virtual machines and are allocated dynamically. The ability to be infinitely
flexible in configurations while managing the entire environment with a single tool is what made View our product
of choice.
Figure 2 – Logical layers of a virtual machine
Provisioning
Provisioning refers to the process of creating and destroying virtual machines. VMware View allows an IT
administrator to rapidly create one or hundreds of virtual machines in a matter of minutes. View relies on templates
to create collections of virtual machines called pools. Each pool can use a unique template giving the VMs it
contains the specific attributes required by the users who will be entitled to use them. These attributes include but
are not limited to operating system, application suite, and the amount of hardware resources that can be allocated.
Once a pool is created, provisioning is a fully automated process. Virtual machines can be automatically destroyed
when a user is done with them and new VMs can be generated in their place.
Managing
Managing the lifecycle of computers can be a daunting task. A significant amount of IT resources are spent
reinstalling operating system and application software in traditional computer labs. Updates often require planned
outages and a great deal of redundant human effort. The following is a quote from the Gartner group about total cost
of ownership of a traditional PC: “For a large company, the cost of purchasing a desktop PC may be only $1,200,
but, kept for four years, the total cost of ownership (TCO) could be as much as $5,867 per year, according to
(Gartner, Inc., 2010)” VMware View provides a single management interface to manage all virtual machine pools.
Templates can be updated offline and used to rebuild pools of VMs with minimal effort and no user downtime. This
feature frees IT resources to work on higher level, strategic initiatives, dramatically reduces TCO of individual
machines, and improves student experience.
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Brokering
By definition, the virtual machines in our private cloud are all housed behind the university firewall. This
protects the devices from malicious software and unauthorized access. The View Connection Broker provides a
means for authenticating the user against Microsoft Active Directory, verifying their entitlement(s), and managing
the session traffic between their end-point device and the virtual machine.
VMware ESX
VMware ESX is a proprietary operating system that creates the hypervisor layer and makes virtualization
on the x86 server architecture possible. The University of Toledo has virtualized nearly fifty percent of its server
infrastructure over the last five years using this technology. At the time of this writing we have just over 260
virtualized servers running on approximately thirty-five physical devices and this number is growing all the time.
VMware View builds on the existing ESX infrastructure to build virtual machines. Because we already had
an existing ESX infrastructure for server virtualization, it was a relatively simple step to start vitualizing the desktop
and to build the VLab.
Conclusion
While opinions certainly differ on the role distance education will play in the future of education, I think it
is safe to say that its prevalence will continue to increase as it has in recent years. Educators will need to embrace
technology that empowers students to be efficient and effective learners outside of the classroom as well as in.
Building a private cloud infrastructure on VMware technology has proved to be an effective means of doing just
this. While there are technical limitations to every solution, we are finding that one of our biggest challenges is
keeping up with the demand for more infrastructure and more virtual machines. As an IT professional, this is the
best kind of problem to have.
Figure 3 below provides an overview of the components required to build VLab. It also illustrates the
process flow for both provisioning virtual machines (in red) and connecting to them (in blue).
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Figure 3 – VLab Architecture Design
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Figure 4 – Power Study Results
The following data are the result of a UT power study conducted by Jeffrey Coyne in Information
Technology with the help of UT electricians. The original data have been modified minimally for easier
display. All measured wattage has been rounded off to the nearest whole number. All costs have been
rounded to the nearest cent. Some columns that were not applicable to the topic at hand were removed.
Device Type
Wyse Terminal
Dell Optiplex 755
Dell Optiplex 755 Energy
Star
Power Off
2
7
Low
Utilization
13
49
High
Utilization
13
84
Screen
Saver
13.000
53.000
Monitor
Off
13
48
7
41
76
46.000
41
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Scenario Two: 24/7/365 student lab OR hospital
In both 24/7/365 computer labs as well as in the hospital, computers are often left on all the time. With
these assumptions in mind the following compares the Dell Optiplex 755 Energy Star with the Wyse
terminals used in our evaluation.
Dell Optiplex 755 Energy Star
Daily - Formula = High utilization + Low Utilization + Screen Saver + Idle (Monitor off)
$/Kilowatt
Hours
Kilowatts
hour
Total
High Utilization
6
0.076
0.075
0.034
Low Utilization
6
0.041
0.075
0.018
Screen Saver
12
0.046
0.075
0.041
Totals for one business
day:
24
0.094
Seven day
week:
7.000
Total for work week:
0.658
Weeks in a
Number of
One week
year
PCs
Total
Grand total for one
$17,117.10
year:
$0.66
52
500
Wyse V10L Terminal
Weekday - Formula = Standard Utilization
Hours
Kilowatts
Standard Utilization
Total for one business
day:
24
0.013
$/Kilowatt
hour
0.075
Seven day
week:
Total for work week:
One week
Weeks in a
year
Total for one year
terminals:
$0.16
52
24/7/365 Blade Center - Formula = Standard Utilization
Standard Utilization
24
4.266
Total
0.023
7.000
0.164
Number of
PCs
Total
500
$4,258.80
0.075
Days in a year:
7.6788
365.000
Total for one year
servers:
$2,802.76
Grand total for one
year:
$7,061.56
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References
Coyne, J (2008). University of Toledo: Research - Information Technology Department. Retrieved October 2008
from http://www.utoledo.edu/it/vlab
Honeyman and Miller (1993). "Agriculture distance education: A valid alternative for higher education?
Proceedings of the National Agricultural Education Research Meeting67-73. Retrieved from
http://en.wikipedia.org/wiki/Distance_education#cite_note-0
Coyne, J (2008). University of Toledo: Research - Information Technology Department.
Stevens, H (2008). “Gartner Says Effective Management Can Cut Total Cost of Ownership for Desktop PCs by
42Per cent” Gartner Press Releases. Retrieved from http://www.gartner.com/it/page.jsp?id=636308
TechTarget (2009). Cloud computing definitions. Retrieved from
http://searchcloudcomputing.techtarget.com/sDefinition/0,,sid201_gci1333074,00.html
Wikimedia Foundations, Inc., 2010. Virtual machine (VM). Retrieved October 4, 2010 from
http://en.wikipedia.org/wiki/Virtual_machine#Definitions
Wikimedia Foundations, Inc., 2010. Wikipedia cloud computing. Retrieved 7 April 2010, from
http://en.wikipedia.org/wiki/Cloud_computing
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