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 Networks Issue 14, January 2011    1 
http://www.inspire.anglia.ac.uk/networks-issue-14
Remote Laboratories and Reusable Learning Objects 
in a Distance Learning Context  
Abstract 
This paper is an investigation into the use of 
virtualisation techniques and remote laboratory 
facilitation for networking, systems, forensic and security
-based modules with specialist computing lab resources 
within the Computing and Technology Pathways, 
allowing students to study elements of those modules in 
a distance learning context. The research explores the 
benefits of bringing a cloud computing approach to use 
of specialist lab resources, where students are able to 
use virtual machines so that a student’s computing 
resources can be accessed from anywhere and can be 
considered as truly portable. 
Keywords 
virtualisation, remote, virtual, laboratory, Web. 
Adrian Winckles (adrian.winckles@anglia.ac.uk), Kalina Spasova (kalina.spasova@student.anglia.ac.uk), Tim 
Rowsell (tim.rowsell@anglia.ac.uk), Faculty of Science and Technology 
 2    Networks Issue 14, January 2011 
1. Background 
Building on the success of work carried out with Peterborough Regional College (PRC) on remotely 
delivering Computer Network Principles (EJ23001S) on a distance learning basis, the primary aim of this 
research is to develop further the use of virtualisation (as explained below) techniques and remote 
laboratory platforms for modules within the Computer Science pathway, allowing students to study 
elements of those modules in a distance learning context. 
The lessons learnt from the PRC experiment suggest that where properly supported and maintained, 
students are not averse to using non-conventional learning methods (especially where students can do 
laboratory type work at a time and place of their own choosing). Two of the areas that need to be 
researched carefully are the support and reliability issues, which as the experiment with PRC showed 
cause the greatest problems. 
2. Aims and Objectives 
To research and develop a software solution for one or more modules within the Computing & 
Technology portfolio of modules, with significant specialist lab computing requirements to deliver 
an alternative distance learning solution. 
To trial a minimum of two differing software solutions in modules (including the solution above) 
requiring significant traditional computing laboratory resources to analyse the effectiveness of such 
solutions alongside the traditional delivery. 
2.1 Longer Term Aims 
Long term goal of developing a part time distance learning BSc Computer Science, as well as 
leading a contribution to developing distance learning aspects for master’s and foundation degrees. 
Potential to use this type of technology wherever specialist laboratory computing resources might 
alternatively be replaced with a virtualisation solution (see Section 5.3) that students can install on 
a reasonable laptop or desktop computer system. 
3. Virtualisation 
The concept of virtualisation embraces a lot of various areas of IT – virtual machines and server, 
application, desktop, data, database and network virtualisation (Fisher & Thacher, 2009). Importantly, what 
actually makes this technology so portable is the concept behind it: to create abstract computer resources 
which are only virtual software versions of something rather than really existent (Michocka &  
Shwartsman, 2008). 
To be more specific – ‘virtualization enables one server or computer to act as many’ (Chu, 2008). ‘Instead 
of keeping your important programs on separate servers so that if one application or server fails, the other 
applications aren’t affected, virtualization software lets you run many applications on the same 
server’ (Robb, 2008). 
A further explanation is given by J. Borck (2002) in his article ‘Virtual virtuosity’, where he says that 
‘virtualization or virtual machine technology is a partitioning technique and introduces a software layer that 
effectively enables multiple, independent operating environments to make use of a single set of static 
resources’. An important concept to note is that of the virtual machine (VM), where an installed operating 
system believes that it is running on actual hardware. 
Virtualisation has been successfully used to teach a wide range of IT disciplines, such as: 
Servers and desktop OS’s 
Distributed Application Development 
Databases 
Networks 
Fisher & Thacher (2009) 
 
 
 Networks Issue 14, January 2011    3 
3.1 Virtualisation Models 
A traditional computer architecture has an operating system installed on top of a hardware platform (as 
shown in Figure 1.), with applications installed on top of the operating system. Within a virtualised system, 
the hardware layer is emulated, and an operating system is built upon that virtual hardware and 
applications on top of the operating system. In such a way, it is possible for one system to run many 
different virtual systems, as shown in Figure 2. 
Figure 1. Traditional Computer Model vs Virtualised Architecture (VMWare, 2010) 
Figure 2. Hardware Emulation and Multiple VM’s (VMWare, 2010) 
4. Relevance to the Student Experience and Learning and Teaching Strategy 
There are changing demographics in these financially troubled times where more ‘home’-based students 
will opt to travel to their nearest university (up to 60 miles is not unknown) to be able to embark on a higher 
education course. For those students undertaking technology-based courses such as engineering or 
computing, this inevitably means that there is much more of a burden to attend laboratory-based classes 
in addition to conventional lectures (which all students attend), both in terms of the travel required and the 
extra carbon footprint/travel costs involved. 
From a widening participation standpoint, technology-based courses have not always been candidates for 
adoption or for delivering in a distance learning context for traditional face-to-face teaching universities. 
Part-time students, those with additional needs, care commitments or from non-traditional university 
backgrounds will have greater opportunity to engage at times convenient to themselves whilst being able 
to maintain their other needs crucial to effectively balancing their lives. 
5. What Constitutes a Remote or Virtual Laboratory? 
5.1 Remote/Distance Laboratory 
According to the Oxford Dictionary the definition for a laboratory is ‘a room or building for scientific 
experiments, research, or teaching, or for the manufacture of drugs or chemicals’. For Computer Science 
 4    Networks Issue 14, January 2011 
students, these facilities need equipment like networked computers, routers, switches and specific 
software applications so that the teaching process can be as productive, fruitful and realistic as possible 
(Machotka, Nedic & Gol, 2007). 
The use of a physical computer lab until recently was the only way to apply in practice the theoretical 
knowledge gained in the classroom. This, however, causes limitations such as time and space restrictions, 
supervision, high costs for maintenance and scheduling for the use of the resources (Nedic, Machotka & 
Nafalski, 2003). All of these can be avoided with the implementation of a distance laboratory solution, 
which is a system that provides ‘efficient user operations, machine and platform independence, secure 
operations, graphical user interface capabilities, high processing bandwidth, and low cost 
maintenance’ (Steidley & Backnak, 2005). 
Interestingly, according to Border (2007) there is not a significant difference in the study process between 
users who learn through onsite experience and those using distance laboratories since ’the Internet has 
enabled conducting of real experiments at any time at any location’ (Machotka, Nedi & Gol, 2007). 
Additional research has revealed that there is ambiguity over what constitutes a remote laboratory. In 
different studies it has been referred to as a web lab (Ross et al., 1997), virtual lab (Ko, 2000) and 
distributed learning lab (Winer, 2000). Despite the confusion, after analysing the different types of 
laboratories, Ma and Nickerson (2006) concluded that the uniting factor between all variations of these 
systems is that they ‘are characterized by mediated reality’ and ‘experimenters obtain data by controlling 
geographically detached equipment’. 
5.2 Virtual Laboratory 
According to Wiseman, Wong, Wolf and Gorinsky (2008), a virtual laboratory is a ‘facility where students 
can access real laboratory equipment remotely’. However, new technologies have furthered the above 
statement and have enabled the manipulation not only of real-world equipment but of its virtualised 
analogies as well, which gives a more specialised meaning of the term ‘virtual lab’. Leitner and Cane 
(2005) support it by saying that ‘any local computer hosting a simulation’ is considered a virtual lab. They 
elaborate even further and use the term to describe a computational grid, used for solving computational 
problems with geographically distant resources. 
5.3 Benefits of Using Virtual Labs 
 
Comparative List of Advantages and Disadvantages of Real, Virtual Remote, 
Laboratory Type Advantages Disadvantages 
Real realistic data 
interaction with real 
equipment 
collaborative work 
interaction with 
supervisor 
time and place 
restrictions 
expensive 
supervision required 
requires scheduling 
Virtual good for concept 
explanation 
no time and place 
restrictions 
interactive medium 
low cost 
idealised data 
lack of collaboration 
no interaction with real 
equipment 
  
Remote 
  
interaction with real 
equipment 
calibration 
no time and place 
restrictions 
realistic data 
medium cost 
only ‘virtual presence’ in 
the lab 
 
Table 1. Comparative List of Advantages and Disadvantages of Real, Virtual, Remote Laboratories 
(Nedic, Machotka & Nafalsk, 2003) 
 Networks Issue 14, January 2011    5 
From Table 1, the comparison of advantages and disadvantages of different types of laboratories by 
Nedic, Machotka and Nafalski (2003), it can be determined that the virtual laboratory is a worthwhile 
solution because of its interactivity and high availability. Previous research at the Rochester Institute of 
Technology (Lawson & Stackpole, 2006), using student satisfaction surveys on virtual labs, found that 
where students were using a virtual lab solution, they achieved 8% better scores on average than those 
students learning the traditional way. 
5.4 Selection of Research Platforms 
From the broad investigations carried out, the remote virtual lab can teach students to use a wide range  
of operating systems and applications to observe/monitor network traffic and to configure various 
computing scenarios without necessarily being on campus. However, as any developing technology, there 
are many obstacles that need to be solved, such as high cost, standardisation and implementation effort, 
but as every service worth having they would be overcome because of the high demand and advancement 
of virtualisation. 
A summary of the solutions investigated is shown in Table 2 and two solutions were selected for use with 
the study. Netlab was selected, as it was already in use and could easily be expanded for certain modules 
and deployment for students. Compared to the other five solutions, Virtual Computing Laboratory (VCL) 
was selected in terms of flexibility, scalability and the broad range of uses it can be put into. It is designed 
to run on a large number of platforms, from blade-servers to lab computers, and to make use of almost all 
virtualisation technologies available, which makes it unique compared to the other five. In addition, it is the 
only one which has been put into such an extensive employment. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Table 2. Comparison between VCL and Other Similar Solutions 
Virtual 
Remote 
Laboratory 
Flexibility and 
Scalability 
Price Implementation 
Effort 
Student Satisfaction 
and Achievements 
VLabNet 
(Powell, 2007) 
Flexible and 
scalable 
Relatively cheap Significant 
difficulties 
High satisfaction and 
practical experience in 
particular subject 
RLES 
(Border, 2007) 
Flexible and 
scalable 
Affordable Manageable Satisfaction and 
practical experience in 
particular subject 
NetLab Depends on 
funds 
Expensive Easy (external 
implementers) 
High satisfaction and 
practical achievements 
in particular subject 
Wisconsin-
Whitewater 
(Villanueva & 
Cook, 2005) 
Flexible and 
scalable 
Cheap Easy Satisfaction and 
practical achievements 
in particular subject 
Techlabs 
(Correia & 
Watson, 
2007). 
Flexible and 
scalable 
Affordable cost Difficult High satisfaction and 
invaluable recourse 
VCL 
(Vouk, 2009) 
Extremely 
flexible and 
scalable 
Varies from 
expensive to 
really affordable 
Manageable 
(experimental) 
High satisfaction and 
broad scope of users 
 
 6    Networks Issue 14, January 2011 
5.4.1 NetLab  
This is a commercial product used widely as an educational tool for Cisco-related courses. NetLab allows 
lecturers and students alike to interact with real lab equipment (see Figure 3) located elsewhere through 
the Internet over a Graphical User Interface (GUI) written in Java (See Figure 4). Virtualisation is used to 
provide the equivalent of lab PCs to interact with the lab equipment. One of the real powers of Netlab is 
the scheduling ability of booking lab equipment 24/7 (as shown in Figure 5). 
Figure 3. Netlab Architecture (Netlab, 2010)    Figure 4. NetLab Academy GUI (Winckles, 2010) 
Figure 5. User Session Booking (Winckles, 2010) 
5.4.2 Virtual Computing Lab 
One of the major virtual lab solutions which has become more than just an ‘in house’ project is VCL – 
Virtual Computing Lab. Adopted by Apache as an incubator project and used extensively by its developers 
at North Carolina State University (NCSU), more than 60,000 virtual machine allocations per semester are 
utilised (Vouk, 2009). What makes VCL appealing is explained by Vouk (2009) in his paper devoted to the 
usage of VCL technology, where it is described as follows: 
A further explanation of the concept of VCL can be found on the official VCL website, which says that: 
“Virtual Computing Laboratory (VCL) is an award-winning open source implementation of a secure 
production-level on-demand services-oriented technology for wide-area access to solutions  
based on real and virtualized resources, including computational, storage, networking and  
software resources.” 
 Networks Issue 14, January 2011    7 
 
Figure 6. Concept of VCL (Apache VCL, 2010) 
 
As seen in Figure 6, VCL is a highly scalable open-source system that covers a wide range of 
technologies, which makes it easy for customisation for any particular needs. 
 
6. Research Methodologies 
To take the project forwards a number of different threads of research were to be undertaken: 
Prototyping Typical Virtual Lab Environment – customised to Anglia’s requirements 
Experimentation using Remote Lab solutions offering standard lab activities and  
assignments solutions 
Experimentation using virtualisation to offer diverging solutions to remote access issues 
Quantitative and qualitative analysis of three independent cohorts’ use of such technologies and 
their experiences. 
These involved both established modules, external partners and research project students in several 
different categories. 
Three module cohorts to utilise Netlab and virtualisation 
EJ230001D – Computer Network Principles 
EJ330009S – Network Technologies 
“One of the primary goals of VCL is to deliver a dedicated computer environment to a user for  
a limited time through a web interface. This computer environment can range from something as 
simple as a virtual machine running productivity software to a machine room blade running high end 
software (i.e. a CAD, GIS, statistical package or an Enterprise level application) to a cluster of 
interconnected physical (bare metal) computer nodes.” 
(Apache VCL, 2010) 
 8    Networks Issue 14, January 2011 
EJ315013S – Network Management 
Prototype project to implement typical Virtual Lab Solution – VCL 
External cohort trialling Netlab for Cisco Certified Network Associate (CCNA) curriculum 
Computer Network Principles and Network Technologies were used to road test the principle of the remote 
laboratory with active cohorts. Network Management was used to test the use of virtualisation techniques 
in both assignments and lab sessions. 
7. Module Delivery Utilising Virtual Machines 
There were several different approaches modelled in the EJ314008S Network Management module: 
Stand alone 
Networked VM’s 
Hybrid VM and Real Equipment 
For the stand alone solution, each student is allocated a sample template for a virtual machine to use (this 
could be a minimal Windows 7 or Windows XP installation or a blank template to install a dedicated 
operating system image). Generally, all that is required is the digital file (an ISO file format), which is used 
to ‘burn’ a CD/DVD. This could be a good starting point for modules like Computer Systems, where at 
present students learn to install operating systems direct onto an empty hard drive in a physical computer. 
For Network Management and similar modules such as Computer Systems, Network Computer Systems, 
Databases Design and Administration and Web Server Engineering, where the interactions between 
computing components need to be explored (client server relationships, for example, such as a web client 
to a web server), it is possible using VM technology to have two independent installed virtual machine 
appliances running on a host computer (so there is no need to dedicate two physical hardware devices to 
demonstrate the concept). By using internal virtualisation technologies, such as network bridging/switching 
technology, two or more virtual machines can be networked together so that these interactions could be 
carried out as a scenario on a remote virtualisation server and accessed with some form of graphical user 
interface. Or by ‘bridging’ the virtual appliances together they could be used on a student’s own 
workstation/laptop (see Figure 7).  
Figure 7. ‘Bridging’ VM Connectivity (Winckles, 2010) 
 
 Networks Issue 14, January 2011    9 
Within technical modules like EJ315013S Network Management, additional scenarios might require the 
virtualising of complex integrated systems managing dedicated hardware (which in some cases might only 
be one system). A scenario for this might be to install these VM’s on some form of remote access server, 
which can then give access to dedicated hardware (ref VCL vs Netlab and Figure 8). 
          ‘Real’ Equipment 
Figure 8. External VM Connectivity (Winckles, 2010) 
Another scenario is to try and use virtual appliances to remove all hardware restrictions whatsoever. For 
example, with networking hardware some Cisco Router software can be run on an open source 
virtualisation solution but this can have license implications (there is still a need to purchase operating 
system licenses) or use alternative open source appliances such as Vyatta to demonstrate the same sort 
of functionality. 
8. Cohort Questionnaire Results 
A total of 45 students were involved in the research, resulting in over 780 hours of online activity  
between them. A total of 20 students responded to the survey, with some very positive results (registering 
84% and above in almost all responses) with some very useful feedback in some key areas to guide  
future development. 
 
 10    Networks Issue 14, January 2011 
 
8.1 Table 3. Post Study Questionnaire (Closed Rating Questions) 
 
 
 
Question Positive 
Was Netlab and its associated equipment easy to use? 76.9% 
Was the level of interaction with laboratory components adequate? 89.4% 
How was the response time of the laboratory components? 84.2% 
Could the routers, switches and the ‘virtual’ PCs be remotely accessed 
once a valid username/password had been supplied and an appropriate 
time slot booked? 
84.2% 
Was the operation of the front end graphical user interface (GUI) for 
Netlab reliable? 84.2% 
Was the operation of the remote ‘lab’ equipment reliable? 84.2% 
Did the interactivity with ‘real’ networking equipment on a remote  
basis help you to better understand networking and systems concepts 
and theories? 
89.5% 
Was the support and feedback you received from the laboratory instructor 
and support staff useful? 89.5% 
Were the online instructions and paper documentation useful in 
supporting your use of Netlab? 94.7% 
Was the online lab exercise information useful when compared to the 
printed lab exercises given to students at the start of the semester? In 
particular, was the lab design accurate and relevant? 
84.2% 
Was there a ‘hands on’ feeling experienced when configuring/
troubleshooting the various lab configurations? 84.2% 
Was the equipment used in Netlab similar to equipment used in a real 
world, networking environment? Is it ‘state of the art’? 94.7% 
How satisfied were you with the laboratory experience gained in this 
virtual laboratory? 89.4% 
 Networks Issue 14, January 2011    11 
8.2 Table 4. Post Study Questionnaire (Open Questions) 
 
9. Conclusion 
From the promising survey results, it is clear that students are ready and willing to engage with  
virtual laboratory resources for a wide variety of benefits that can be achieved. However, they want  
such resources to be available alongside conventional learning so they can mix and match to  
their requirements. 
The biggest barrier to successful deployment of virtual lab resources is the support that must be available. 
If the system is not available for the students when they want to use it and no support is available in a 
meaningful timeframe, students might be turned off from using the facilities. 
The theoretical and practical approaches in the evaluation of virtual laboratories have resulted in reaching 
the conclusion that VCL would be an invaluable asset in combination with other specific teaching tools, 
such as Netlab, when some resources cannot be wholly virtualised (e.g. like the routers in Netlab). Whilst 
investigating the concept of VCL and contrasting it to other similar virtual remote laboratories, it turned  
out that the scalability and flexibility of VCL make it a more advanced solution in terms of its broad  
scope of utilisation. Additionally, its open source scripts can be used in different combinations of 
equipment and virtualised software, which means that it can be customised to fit any cost, availability  
or usability requirements the department might have. The prototype system has successfully 
demonstrated provisioning over the Internet utilising both Windows XP and Linux environments but still 
requires supervision. 
Several issues caused some concerns for future deployment. For a prototype system, deploying all the 
services on one hardware platform was fine, but for a future production deployment, dedicated systems for 
both the user front end provisioning system and another for the VM hosting would be required. Another 
Question/Statement Response Rate Comments 
Have you experienced any 
problems or issues? 
43% experienced 
problems vs 47% 
who did not 
Almost equal split 
What changes would  
you make? 
62% would make  
a change 
Changes include: 
Simultaneous connection to  
the resources 
Faster connection 
Virtualised the routers  
and switches 
Extended minimum session 
More online help 
Would you prefer a purely 
online solution or mixed 
(blended learning)? 
84.2% for blended 
compared to 5.2% 
for purely online 
  
Do you prefer using 
conventional hardware 
resources or combined 
virtualised and hardware-
based resources? 
42% preferred 
hardware and 47% 
preferred 
combination 
  
Does virtualisation aid 
learning without complex 
configuration/installation? 
79% felt it  
aided learning 
Especially if such technology can 
be made ‘portable’ 
 
 12    Networks Issue 14, January 2011 
area of concern is the security infrastructure necessary for students to utilise remote labs can be too 
restrictive and not dynamic enough to manage the incoming connections 
9.1 Key Recommendations 
Make virtualisation technology a core delivery in the Computing and Technology programs; adding 
the technology to all applicable modules makes the delivery of core Computing modules at partner 
institutions much easier, as the software image can be ‘portable’. 
Develop model for delivering ‘portable’ student assignments and lab work, which can be delivered 
locally or remotely using virtualisation technology. 
For dedicated VM delivery (dedicated VM per student), supported hardware and managed ‘front 
end’ on dedicated systems are required (for managing user sessions). 
By making more resources available generically using virtual machines, computer labs could in 
theory be used to offer functionality only seen previously in specialist labs. (However, the need for 
specialist labs still needs to underpin student learning, as noted by student survey responses.) 
9.2 Future Work 
The VCL platform prototype has showed much future potential but needs to be customised to 
deliver a stable provisioning front end so that students/lecturers can allocate and access virtual 
resources as required. 
Evaluate how support might be offered to students in the future for a successful 24/7 operation. 
Expand the ‘portability’ aspect of using virtualised lab facilities within all computing modules. 
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