The Role of Cisco Virtual Internet Routing Lab in … Role Of Cisco Virtual Internet Routing Lab In Network Training Environments Bradley Herbert 1 Chapter 1 Contents 1. Introduction

The Role of Cisco Virtual

Internet Routing Lab in

network training

environments

Research Proposal

Author

Herbert, Bradley Mark - herbm001

Division

School of Information Technology & Mathematical Sciences Bachelor of Information Technology (Honours)

Supervisors

Wigley, Grant Brian

July 2015

Australia

Version 1.1

The Role Of Cisco Virtual Internet Routing Lab In Network Training Environments

Bradley Herbert

1 Chapter 1

Contents

1. Introduction ............................................................................. 6

2. Literature Review ..................................................................... 1

2.1 Teaching Methodologies ........................................................................................... 2

2.1.1 The role of practical-based education in networking training ............................ 2

2.1.2 Using Network Simulators for education in networking ..................................... 7

2.2 Networking Learning Platforms ............................................................................ 11

2.2.1 Types of Education Platforms ............................................................................ 11

2.2.2 Physical Equipment ............................................................................................ 13

2.2.2 Cisco Packet Tracer ............................................................................................ 18

2.2.3 GNS3 ................................................................................................................... 27

2.2.5 Common Open Research Emulator (CORE) ....................................................... 29

2.2.6 Miscellaneous Platforms .................................................................................... 32

2.2.7 Cisco Virtual Internet Routing Lab ..................................................................... 34

2.3 Summary .................................................................................................................. 39

3. Methodology ............................................................................ 1

3.1 Outline of Current Research Methodologies .......................................................... 1

3.2 Experimental Design ................................................................................................. 2

3.2.1 Recruitment Procedures ...................................................................................... 2

3.2.2 Overview of the experiment ................................................................................ 4

3.2.3 Implementation ................................................................................................... 5

References ..................................................................................... 6


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Declaration

I declare that this thesis titled, ‘The Role of Cisco Virtual Internet Routing Lab in network

training environments’ is, to the best of knowledge, original work and that all sources used in

this thesis is acknowledged using IEEE referencing. This thesis, or the research therein has

not been previously submitted by me for any assessment to any educational institution or

university.


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Acronyms

ACRONYM WORD

VIRL Cisco Virtual Internet Routing Lab

STP Spanning Tree Protocol

UNISA University of South Australia

CORE Common Open Research Emulator

RAM Random Access Memory

LTS Long Term Support

OSPF Open Shortest Path First

BGP Border Gateway Protocol

IP Internet Protocol

TCP Transmission Control Protocol


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Glossary

WORD MEANING

SPANNING-TREE PROTOCOL A network protocol that shutdowns links on

a switch intended to be used as backups to

prevent loops from occurring.

SWITCH A device specially designed to forward

frames on a computer network. A smart

hub.

SWITCHING A switch making decisions on where to

send traffic based on source/destination

MAC addresses.

ROUTING A router making decisions where to send IP

packets based on source/destination IP

addresses. Rewrites MAC addresses.

VIRTUALISATION Virtualisation is the allocation of

computing resources to so-called guest

operating systems to allow multiple

operating systems to run on a single

machine.

EMULATION Software that converts instructions

designed on one type of CPU to that of the

host system, enabling the program to run.


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Abstract

Teaching advanced network concepts is challenging because it often involves teaching

complex concepts not easily understood by students. To help improve students’

understanding, simulators are often used in network training environments but the literature

supports the premise that using simulators can be inadequate to enhance understanding. Three

factors influence this. Firstly, the students’ perception of the simulator. Secondly, the

technical application of the simulator i.e. how good is it at simulating the network? Is it

limited? Thirdly, the use of the simulator and how the learning is assessed or improved.

Cloud computing, decentralised lab environments and virtualisation can reduce costs,

maintenance and enhance student learning of networking. Often, these relied on real

equipment because virtualisation of Cisco devices was poor. The Cisco Virtual Internet

Routing Lab (VIRL) provided the feature set to fill in the limitations in current simulation

tools such as limited functionality and the reliance on physical equipment. While Cisco VIRL

is a useful tool for testing network designs, no research has been done to demonstrate its

effectiveness and role in a networking training environment. A practical approach is

necessary, according to the literature and should be supplemented with a theoretical approach

for understanding. This paper presents current research on simulators and concludes that no

tool is adequate for learning advanced networking and that Cisco VIRL is a possible tool to

address this issue.


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1. Introduction

Cisco Virtual Internet Routing Lab (VIRL) is a new software package released by Cisco in

December 2014 designed to virtualise a networking environment[1] [2]. This is beneficial for

technicians testing a network design before it is rolled out onto a production network1. The

nature of Cisco VIRL gives it potential to be used in training environments by Cisco certified

instructors for teaching advanced networking concepts to students and trainees with diverse

learning needs.

Teaching subjects like networking can be challenging because of the different learning needs

of the students. For example, some students live in remote areas and may not be able to get to

the educational institution to perform hands-on activities, some students have disabilities that

may impact their ability to interact with physical equipment, others become frustrated or lose

focus when doing repetitive tasks such as cabling a physical network every time they do a

practical exercise and some students prefer a theoretical approach. Nevertheless, the current

research demonstrates that there are two forms of learning, essential for learning advanced

networking concepts. Firstly, there is abstract conceptualisation, which is developed through

lecturing and memorising of important concepts. Secondly, there is active experimentation

which is best developed through a practical approach [3].

Delivering the first learning method through lecturing is easily achieved and is tradition in

most universalities worldwide. But delivering the second method is challenging and often

poorly delivered. In third-world countries such as Ethiopia, hands-on practicals are rare

because of insufficient funds and resources[4]. Implementing a practical lab is often

expensive and time-consuming [5]. Use of the equipment is often restricted or shared by a

1 A network that transmits traffic for the operational day-to-day running of a company, government or home.


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number of students. As a result, inexpensive simulation-like tools such as Cisco Packet

Tracer are used as an alternative[4]. But use of simulation tools, such as Packet Tracer may

lead to a perception by students and instructors that students cannot apply the problems to

real-world examples[6]. These simulators also lack a great deal of real-world functionality,

that is, how the software installed on servers behaves in a real environment. This restricts the

student to a narrow subset of networking concepts and, therefore, may fail to provide the

student with a full perspective of how networks operate in reality.

While these problems have been extensively addressed in the literature [6-10], often the

research has only aimed to solve one or two of the aforementioned problems. In the paper

titled, ‘Assessing the Effectiveness of Remote Networking Laboratories’, the role of practical-

based labs in remote educational environments is explored. Now while a remote lab improves

accessibility to the lab environment and enhances realism, it does not solve the financial

problems or the concerns associated with maintenance[5]. Likewise, software tools often lack

realism, degrading a student’s learning experience[9]. Consequently, no solution appears

solve the challenges faced in teaching advanced networking in training environments.

In early 2015, development of Cisco Virtual Internet Routing Lab (or better known as VIRL)

progressed. This new tool not yet explored in the literature offers unique features not

available in previous software based tools. In particular, Cisco VIRL was designed to test

configurations of Cisco equipment in a virtual environment. In simple terms, Cisco VIRL

effectively runs an almost identical version of the operating system found in enterprise Cisco

routers and switches using virtualisation2. In theory, this means that Cisco VIRL offers a

2 Virtualisation is the allocation of computing resources to so-called guest operating systems to allow multiple

operating systems to run on a single machine.


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sense of realism and unlike Packet Tracer is not a cut-down version of the Cisco operating

system.

Unfortunately, although Cisco VIRL has the potential to replicate a real networking

environment, its impact, whether positive or negative on student education is unclear. The

literature does not make any mention of VIRL because it was not released until December

2014. This thesis investigates Cisco Virtual Internet Routing Lab (VIRL) and its application

and role in an academic environment to teach advanced networking concepts. Because

Packet Tracer and physical equipment may not necessarily provide students with a sound

understanding of computer networks, it is important to assess the feasibility and practicality

of using Cisco VIRL for this purpose.

Cisco Virtual Internet Routing Lab is technically better than Packet Tracer in terms of its

functionality and feature set. However, this does not necessarily mean that the students’ and

trainees learning will be improved. This is because a student’s perception of the tool can

negatively impact their education [11].

The following research question is posed and will be investigated:-

“What role does Cisco Virtual Internet Routing Lab play in network

training environments to help students and trainees understand advanced

networking concepts?”

It is hypothesised that Cisco VIRL plays a significant role at enhancing the realism of the

simulated networking environment, increasing engagement and helps students understand the

behaviour of production networks. This hypothesis will be tested by conducting an

experiment on a group of networking students and several staff members enrolled at the

University of South Australia, which aims to test their perceptions of the tool, their use of the


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tool and to measure their understanding of key networking concepts after they have used the

tool to determine how well the tool has helped develop their learning of networking concepts.

In the next chapter, the arguments and counter-arguments will be examined in light of the

literature available. Chapter 3 specifies the methodology and the processes to be undertaken

to answer the research questions.


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2. Literature Review

This section presents previous research in respect to teaching networking, including; the

importance of a practical learning approach, the weaknesses of relying too much on a

theoretical approach, the student’s perceptions of various simulators, the importance of

developing skills for the workplace, an overview of network simulation tools including how

they should be used to improve learning.

The first section outlines research in respect to the use of a practical teaching method and

why it is essential for student’s learning. The subsection provides an overview of network

simulators, including their benefits and weaknesses and why they fail to improve learning.

The same subsection also outlines the perceptions of using simulators, which although

positive, do not indicate successful learning and understanding. The second part of the

literature review is a comparison of various types of networking simulators, tools and

platforms that could be used to teaching networking and why each solution is inadequate to

achieve this goal. The first subsection briefly lists and categorises the different kinds of

platforms. The second subsection outlines the benefits and weaknesses of using physical

equipment. The third subsection outlines the benefits and weaknesses of using Cisco Packet

Tracer. The fourth subsection outlines GNS3, its benefits and its weaknesses. The fifth

section explores the Common Open Research Emulator, including its weaknesses and

benefits. The sixth section outlines various other platforms and summarises key benefits and

weaknesses of each tool, or why they are not suitable for a training environment. The seventh

section summarises VIRL, including its advantages and disadvantages and how this tool will

be further explored in the research. The third and last major section of this literature review is

a summary that summarises the literature review and emphasises the gap in the literature.


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2.1 Teaching Methodologies

This section presents current research on studies, suggesting that a practical approach is

essential for developing soft skills, such as problem solving. The weaknesses of the

theoretical-only approach will be outlined, as well as the perceived or real learning

difficulties faced by students who are not familiar with a practical environment and how this

may impact their performance in industry. In conclusion, the section will outline why a

combination of both theoretical and practical learning is supported by the literature and

strongly recommended. The drawbacks of relying too much on simulators will also be

addressed in this section.

2.1.1 The role of practical-based education in networking training

This section presents previous research on the effectiveness of the traditional lecturing

approach to teach subjects such as networking and engineering and identifies the weaknesses

of this approach. This subsection also outlines why a practical-based approach needs to be

supplemented with lectures for effective understanding of networking concepts.

A study by Holvikivi, J suggests that undertaking practical exercises are essential for students

to develop motor skills and to enhance the areas of the brain that drives problem solving and

analytical thinking[4]. Unfortunately, practical exercises alone often rely on a student’s

mental model of technology and their imagination[6] [12]. The abstract concepts of

networking have to be understood using imaginative processes or illustrations[6]. This

requires a careful balance between a theoretical and practical approach.

In third-world countries including China and Ethiopia, the money or infrastructure for a

practical lab does not exist. Often, learning networks relies on lectures, exams and limited use

of Packet Tracer. But the effectiveness of Packet Tracer has been questioned by several


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academics which perceive Packet Tracer of making students too reliant on step-by-step

processes[6]. A comparison between western educational institutions and those in third-world

countries such as China showed interesting trends of vastly different learning methods. In

countries where practical learning is not used, those students would often struggle with

practical-based tasks and would require additional support to get through it, but the students

did perceive practical learning to be beneficial. The study suggested that use of lecturing and

exams without a practical approach may lead to bad learning habits such as rote learning or

failure to apply the content. The study by Holvikivi, J confirmed this hypothesis. When

international students enrolled into an education institution in the United States, interesting

observations were made. For instance, the international students struggled to get started with

the labs and without additional support, would rarely complete them. The study investigated

why this divide existed and found that it is likely due to the absence of technology in the

homes of third-world countries. At a young age, children in western countries learn from

others around them by observing them and using technology such as turning on/off lights and

watching technology work[4]. When children go to school, they use computers and

technology in a lab environment, learning about the technology and becoming familiar with

it. This influences how they think and learn about technical subjects[4]. In comparison,

Ethiopians, for example, do not grow up experiencing technology and consequently this

impacts their understanding of technical subjects i.e. engineering and information technology.

This may lead to them struggling to start the labs. The study also implies that experience in

using technology enhances understanding. In the absence of technology, third-world students

did not have the same experience as western students and this leads to learning difficulties.

Also, lack of practice on the labs may present learning challenges because of less experience.


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Because students not familiar with technology may struggle with practical labs, this possibly

also suggests that they may not be able to apply their skills in the workplace. Therefore, the

study strongly recommends that these international students be given additional practical

experience to give them the level of understanding required[4]. From the study, we can

deduce the following:-

A) South American students are taught networking using a theoretical approach.

B) South American students, according to the study, struggle to apply content to labs.

C) The workplace requires hands-on use of the real equipment

D) Therefore, South American students are not prepared for the workplace.

E) Therefore, this method of training is not effective.

From the study, we also deduce the following:-

A) North American students have grown up experiencing technology.

B) North American students are educated using lectures and labs.

C) North American students easily apply concepts to the labs due to prior experience

with technology.

D) Therefore, they have skills preparing them for the workplace.

E) Therefore, this method of learning is effective

In conclusion, it follows by logical reasoning that both a practical and theoretical approach is

the preferred approach to provide the best learning outcomes. There is another advantage to

practical training as well. Employers are wanting employees with skills in using physical

networking equipment[13].

According to a literature review recorded in a New Zealand paper titled, ‘Does Embedding an

ICT Certification Help Align Tertiary Programs with Industry? A Study of CCNA


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Perceptions’, the majority of employers believed skills in Cisco were important or beneficial

to have and that CCNA skills had a large impact on successful employment[13]. The same

paper highlights the need for a teaching tool that will allow instructors to focus on key

learning areas perceived as important by industry. However, in many cases, the instructor is

constrained to the labs by Cisco and customising or creating new labs is a challenge[9].

Learning about computer networking using the practical teaching method can also be

beneficial for employers in terms of providing transferrable skills. According to a study cited

in ‘‘Does Embedding an ICT Certification Help Align Tertiary Programs with Industry? A

Study of CCNA Perceptions’, some participates indicated that learning to configure a Cisco

router or switch provided them with the ability to transfer those skills to routers and switches

offered by third-party vendors[13]. Others also made mention of the importance of using

other hardware such as the Cisco ASA Appliance, which is not in the CCNA curriculum[13].

Tools provided by Cisco such as Packet Tracer cannot provide an unlimited array of

simulated hardware devices. Consequently, the literature is suggesting the importance of

functionality that extends beyond the CCNA framework. Troubleshooting skills were also

viewed as very important in the study[13]. However, troubleshooting requires skills that

takes time to develop and usually, this involves practice in a simulated environment.

Interestingly, those in industry, according to the aforementioned study, listed cabling a

network as important, switching, VLANs, wireless LANs and equipment configuration [14].

Some alternative simulation tools that will be discussed further in this chapter do not support

VLANs or switching. The study suggests a perception that having CCNA qualifications may

lead to improve communication with experts in industry and lead to better understanding.

Furthermore, troubleshooting networks leads to improved skills in communication, teamwork

and problem solving[13]. Because of the perceived industry need for networking skills, this


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motivates the discussion of evaluating a software tool that replicates the behaviour of a

physical network lab and by doing so makes networking courses more accessible and

available.

The study mentioned in ‘From theory to practice: Adopting the engineering approach’[4],

problem solving is considered an important skill in both academia as well as industry that has

to be practiced using a hands-on practical approach[4, 13]. A theoretical approach involving

lecturing and exams is not sufficient for providing real-world problem solving, experience

and transferral skills[4, 13]. Consequently, the graduate is ill-prepared for the workplace

because he fails to fulfil industry expectations.

Therefore, it is clear from the literature that a curriculum that incorporates a practical

component is absolutely essential for the development of in-demand industry skills such as

problem solving and troubleshooting. Unfortunately, implementing a practical lab to provide

the necessary practical is challenging in terms of costs and maintenance[15]. Without prior

experience, students from impoverished nations may not have the sufficient background to do

the practicals without additional support[4]. In the case of networking laboratories, these

cannot be easily modified to support the individual learning needs of the student, creating

additional learning barriers[9]. The current research does not address these issues in sufficient

detail.


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2.1.2 Using Network Simulators for education in networking

This section explores the role of using networking simulators as an education tool in

networking training courses and evaluates the effectiveness of using simulators to help

students and trainees understand advanced networking concepts.

Simulators are frequently used by instructors to demonstrate concepts and to reinforce

concepts taught in lectures[16]. One of the widely used tools in networking education is

Cisco Packet Tracer. This tool, often referred to as a ‘network simulator’[8] is considered by

Frezzo et. al. to not be a complete network simulator because it does not simulate the entire

network stack[15]. The same paper suggests that a simulation environment alone is

inadequate unless the students have a developed way of thinking and an understanding of the

conceptual concepts. A similar view is mentioned in the paper titled, ‘Using a Network

Simulation Tool to engage students in Active Learning enhances their understanding of

complex data communications concepts’. This paper suggests that the simulator must be used

to provide feedback and recognition of mistakes and suggests that use of the simulator for

demonstration purposes is unlikely to improve learning outcomes[16]. The learning outcome

generated by simulators might be perceived and not truly enhancing learning at all. Students

often use simulators to finish the set activity with as least amount of effort as possible. But as

noted in the paper, ‘Using a Network Simulation Tool to engage students in Active Learning

enhances their understanding of complex data communications concepts’, this is not the goal

of the simulator. Instead, the simulator should be used to improve understanding[17]. A

survey was conducted on a number of lecturers at Malaysian Polytechnic Institutions suggests

that, while students can easily follow the lab sheet to complete the assigned tasks, they

struggle with any slight variation to the lab-sheet and struggle to apply what they have

learned[6]. One lecture in the survey commented that it seems that the students learned


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nothing and the data from the survey suggests that the simulator tool, Packet Tracer, provided

no actual improvement to learning because it was used to complete the tasks and not to

encourage deeper thinking[14, 16].

According to a survey in the paper titled, ‘Survey on the Challenges Faced by the Lecturers

in Using Packet Tracer Simulation in Computer Networking Course’, some of the

interviewed lecturers made some quotes concerning the learning of the students who used the

simulation tool.

“Students are not able to answer the questions or execute any basic

configuration instructions learned at the initial stages of the course; it

seems as if the students have never learned them. It forces us to repeat

and repeat the process, this is time-consuming. Students only manage to

follow laboratory instructions, step-by-step but they fail to understand the

concept or theory used in the laboratory activity. This problem is

prominent for the topics like routing protocol, subnetting and ACL.

Students only memorize the instructions or the theories learned without

really knowing the actual time or circumstances that the instructions or

theories should be applied.” (Polytechnic Lecturer 2: CCNA, Program

Head, Resource Lecturer, in Survey on the Challenges Faced by the

Lecturers in Using Packet Tracer Simulation in Computer Networking

Course, p. 13, emphasis added)[6]


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The paper, ‘Using a Network Simulation Tool to engage students in Active Learning

enhances their understanding of complex data communications concepts’ emphasises that

getting a student to configure a device will not improve understanding or enhance

learning[16]. Evidence for this seemed was also supported by the statement of the lectures in

the paper, ‘Survey on the Challenges Faced by the Lecturers in Using Packet Tracer

Simulation in Computer Networking’ that suggested that key networking concepts had to be

repeated to students[6]. When the simulator is used for the purposes of illustrating a student’s

lack of understanding, errors, misconceptions and getting them to fix the problems by

applying learned knowledge, a deep understanding was obtained, according to the study[16].

Though the education of networking is not addressed, Dr. Teresa Coffman in the paper titled,

‘Using Simulations to Enhance Teaching and Learning: Encouraging the Creative Process’

suggests that simulation experiences should be realistic to allow the student to apply

knowledge to a given problem or scenario. Simulation experiences, according to Coffman, T,

improves both education and application of knowledge to a specific problem[17]. Students

involved in the simulation should be delegated roles and feel as though they are taking

responsibility for their learning while in that role. Simulations also improve experience,

problem solving skills and improved student awareness[17]. Therefore, it is how the tool is

used rather than what tool is used, that leads to better learning outcomes[16].

Simulators play several roles in the education of networking concepts. Firstly, they mimic, as

close as possible, the behaviour of real networks[5]. Secondly, they provide the tools for

those working in industry to refresh their skills. Thirdly, they provide a platform for students

to troubleshoot networks, problem-solve and to engage in deeper thinking[16] [17]. Fourthly,

they provide (somewhat limited) networking packet and traffic analysis[16]. Fifthly, they

provide a cost effective supplement or alternative to expensive physical labs[5].


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Even though simulators provide a sense of realism and allow traffic analysis, these aims of

the simulators are limited[9]. In general, simulators only replicate a limited number of

features found on physical network devices[18]. Furthermore, as newer technologies become

available, the simulator has to be reprogrammed (or updated) to support the new features[5].

Because networking often incorporates propriety devices such as Cisco, it is not feasible for a

simulator to replicate all the necessary components, resulting in a limited system[18]. As a

result, in terms of realism and network analysis, simulators can only provide a limited

environment. Even a paper, ‘Pedagogical evaluation of simulation tools usage in network

technology education’ states that simulators cannot replace real equipment[5].

The other problems with simulators is that many of them are designed for research purposes

or testing and are not designed for education[5] [9]. Their difficulty makes them an

impractical solution.

Network simulators such as CORE, GNS3, Packet Tracer and even Cisco VIRL [19] [9] [7]

are not merely simulators, though they may appear to be such. Cisco VIRL and GNS3 use

emulation/virtualisation to fully replicate the Cisco IOS, providing a full feature-set[18].

Packet Tracer contains additional features not found in a traditional network simulator and

CORE integrates both emulation and simulation to replicate the networking experience[19].

Because they differ significantly from software-based simulators, they will be discussed in

the next section. It is important to note that emulation and virtualisation helps overcome the

limitations of simulators in terms of realism and functionality. The problem is finding an

emulator or virtualisation solution that replicates routing, switching and which can do such

things lawfully. Prior to 2015, no such solution existed, though Cisco Virtual Internet

Routing Lab potentially supports these features.


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2.2 Networking Learning Platforms

In this section, several networking learning platforms will be discussed and, although they

are used for network training, the limitations of each tool will be outlined.

2.2.1 Types of Education Platforms

The following table is constructed from the data available in the literature.

Tool Category Examples Use Cases Limitations

Physical Lab N/A Full sense of realism Cost / Maintenance

Visualisation Tools Cisco Packet Tracer Practice Networking Limited commands

Software Simulators NS-2 Protocol simulation Difficult to use

Emulation /

Virtualisation

GNS3, Core, VIRL Testing Networks No Switching

Table 1 Network Learning Platforms Comparison


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Network Simulation tools can be categorised as followed:-

2.2.1.1 Physical Lab

According to the literature, there are two types of physical labs [20]. They are:-

I. Centralised: Students connect to, or use physical equipment at their educational

institution to practice their networking skills and/or to learn networking.

II. Decentralised: Students use their own equipment to practice their networking skills.

2.2.1.2 Software Simulators / Visualisation Tools

Software simulators and/or visualisation tools available include [7] [9] [12]:-

J-SIM

NS

Partov

NetSims

Cisco Packet Tracer (also a visualisation tool)

2.2.1.3 Emulation / Virtualisation

Virtualisation or emulation software is used to replicate the realism of Cisco devices [1] [19]

[21].

Cisco Internet Virtual Routing Lab

GNS3

Common Open Research Emulator (CORE)


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2.2.2 Physical Equipment

In tertiary education institutions like universities, it is not uncommon for separate physical

networks to be setup to allow students to practice on real-equipment. This greatly enhances

realism and accurately replicates the networking environment. Unfortunately, physical

equipment presents a number of technical and learning challenges. Firstly, the costs to

purchase and maintain physical equipment is high [5]. The hardware becomes out of date

within a few years and constantly needs to be replaced, adding to maintenance and

downtime. Secondly, there is the on-going electricity costs to power a separate physical

network that utilises probably less than 5% of the total resources[18]. The remainder

resources are not used, however, a separate network is necessary for security and stability of

the university’s production network. Due to budget restrictions, many universities often

interconnect the practice networks with real production networks to cut down on costs. This

design decision means that it is difficult to allow the student to practice with key elements of

the network[9]. Thirdly, to save costs, limited equipment is purchased and students work in

teams to configure the network. Now while teamwork provides useful skills, it follows that

some students will get less experience than others[7] [20]. Select students may hog the

equipment and some students may not get the hands on experience they need. Fourthly, using

physical equipment may not lead to understanding. In the paper titled, ‘Design Patterns for

Learning and Assessment: Facilitating the Introduction of a Complex Simulation-Based

Learning Environment into a Community of Instructors’, the author argues that physical

equipment alone is not enough to provide understanding. Therefore, the use of physical

equipment needs to supplemented with a software visualisation tool, for example, Packet

Tracer[15]. Assistant Professor, Sheikh Raashid Javid in his paper, ‘Role of Packet Tracer in

learning Computer Networks’ also argues that Packet Tracer’s features play a key role in the


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education of students learning computer networking[8]. Therefore, physical equipment must

be supplemented with visualisation tools such as Packet Tracer.

The literature supports the premise that use of physical equipment is necessary for the

education of students learning advanced networking concepts [5, 13, 22]. Furthermore,

experience in using physical equipment is perceived as a useful skill in the workplace and

improves the chance of successful employment[23]. Unfortunately, physical equipment is

both time-consuming and costly to maintain [9] [5] [18] . The author, Woratat

Makasiranondh et. al in the paper, ‘Pedagogical evaluation of simulation tools usage in

network technology education’ gives an illustration of how much it might cost to provide

students access to physical equipment. If a student is supplied with access to one router and

one Cisco switch, the costs could be $50,000 Australian dollars per student. In addition to the

initial purchasing cost, there is also the on-going costs associated with maintenance and

support. It is suggested that practical labs would require at least 20 hours per week of

attention to keep maintained. Wear and tear may result quicker because students are

constantly connecting and disconnecting cables each time a practical exercise is ran and this

increases replacement costs because of higher failure rates. There is also the on-going

demand to keep up with the latest software installed on the router or switch. The IOS needs to

be updated frequently, which adds to costs and administrative overhead. Eventually, the

router or switch may not support the latest version of the IOS and will need to be replaced

[5].


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Setting up the physical equipment in preparation for the lab and cleaning up after the lab

often wastes critical learning time and this degrades a student’s production [24]. There needs

to be a way of managing the equipment and to allow remote access of the equipment[22]. For

example, configurations need to be wiped after each session to provide a fresh configuration

for each exercise. Consequently, management software needs to be configured to allow this

process to occur automatically, adding to the costs.

In many cases, universities use a web-based front-end to physical equipment called NDG

NetLab [22]. This solution provides remote access and management of physical equipment at

any time of the day. After each session, configurations are wiped and/or restored to provide a

fresh environment for each subsequent student [3]. NetLab provides a number of advantages

including; reduced administration of the lab environment, the infrastructure to establish a

virtual network lab hosted in a cloud infrastructure, accessible from anywhere, allocation of

resources only when they are needed and automation of tedious configuration tasks. Student

perceptions of NetLab are also positive with many indicating that it helps improve their

learning [3].

Use of NetLab does have its disadvantages. Firstly, the solution is high-maintenance and

expensive[10]. Secondly, NetLab uses fixed topologies and because physical equipment

topologies cannot be easily redesigned, it is not possible to tailor NetLab to the diverse

learning needs of students [3]. Thirdly, NetLab is not user-friendly for people with special

requirements such as blindness or vision-impairment[10]. Most western countries such as

Australia requires the education institutions to make reasonable adjustments to ensure that

people with disabilities have equal access to the education environment. Fourthly, NetLab has

used the Java runtime to provide access to the underlying technologies. This means that

NetLab cannot be used on tablets or smartphones due to their lack of Java support. Sixthly,


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because students are not seeing and interacting with the physical equipment, key tasks such

as cabling are not done, resulting in less experience [3]. Therefore, NetLab is not the best

solution for overcoming the technical and financial issues associated with using real

equipment.

In order to provide education support for long-distance education students, physical

equipment must be made remotely accessible. This can be inherently risky in terms of

security and ensuring that the infrastructure cannot be accessed by unauthorised people [3].

Best design practice recommends that production and training networks be separated from

each other to minimise disruption, but this presents management and cost issues.

Furthermore, it is possible that untrained students might damage the equipment, adding to

replacement costs [8] [24]. Another issue that might arise is that students may not be able to

access the remote lab because of a slow Internet connection [20]. Solutions to address these

problems involve spending a lot of money and funding for practical labs from the government

is usually limited[22].

To reduce the purchasing, maintenance and operating costs of a local and/or remote

laboratory, several approaches have been done over the years. One of the approaches is to use

virtualisation to help reduce the actual hardware being used [9] [18] [3] . The issue with

virtualisation, especially in times past, was that it required a platform that would accurately

virtualise Cisco equipment. Until recently, the only viable solution was GNS3. But its lack of

features to support all of the CCNA curriculum meant that he had to be supplemented with

physical equipment and/or Packet Tracer[24]. The second approach outlined in the paper,

‘Exploring virtual environments in a decentralized lab’ also uses virtualisation but uses a

decentralised lab model to reduce the strain of resources on the campus infrastructure[20].

This means that virtual machines are ran on student’s home computers rather than on a


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remote server at the campus. As a result, the costs are lower because instead of a centralised,

high costing lab, the resources are used on each student’s local computer. Because of recent

advancements in home computing, most computers have sufficient RAM to run the virtual

machines needed to complete the lab exercises. While the virtual machines provide packet

sniffing and intrusion detection tools, the use of VMWare Player or VirtualBox alone is not

enough to virtualise Cisco equipment. A decentralised lab solution also assumes high-end

computer systems to run the virtual machines and additional work by students to setup on the

virtual machines with the added risk of confusion or failure to complete the labs because of

errors. To overcome this problem, the paper used a centralised lab as a backup to provide

students with continuous access. This would lead to reduced costs as the hardware would not

overstressed by many students but only used in the event of a system failure. However,

according to a survey, approximately 89% of all students preferred the decentralised lab

solution, rather than a centralised lab. One of the reasons for the decentralised lab approach

was because of the connection to the campus lab environment was too slow[20].

It is clear that every solution has a trade-off that greatly impacts the learning outcomes of

students.


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2.2.2 Cisco Packet Tracer

Cisco Packet Tracer, a simulation and software visualisation tool, is provided freely by Cisco

to students enrolled in a network academy program [24]. According to a study by Holvikivi,

J, Packet Tracer is sometimes used in improvised nations as a substitute for using real

equipment[4]. This because it uses minimal hardware resources, runs on a variety of

platforms and is very cost effective [7] [15] . Cisco Packet Tracer has an array of advantages

over the use of physical equipment. Firstly, it is easier to install and use of it virtually costs

nothing in contrast to physical equipment that costs thousands [5]. Secondly, unlike

traditional network simulators, Packet Tracer’s visualisation features and simulation mode

greatly helps students visually see the packet movement through the network and this

arguably leads to improved learning [7] [8]. Thirdly, unlike physical equipment, Packet

Tracer requires very little amounts of disk space and RAM because it is only mimicking the

environment. No actual packet transmission is occurring [9]. Fourthly, because Packet Tracer

does not actually use any physical network devices, there is no risk of damage or disruption

occurring to the network [15]. Fifthly, Packet Tracer also provides the tools to allow

instructors to set assessments, assignments, tests and activities. In addition, it is possible to

use Packet Tracer for collaborative projects [8].

As noted in the paper, ‘Pedagogical evaluation of simulation tools usage in network

technology education’, Packet Tracer is virtually free in comparison to local or remote

practical labs that potentially costs thousands of dollars to build and maintain [5].

Furthermore, Packet Tracer is portable3 and can be deployed at home for additional practice.

Packet Tracer is not only a networking simulator. It combines an array of features such as a

3 Portable means that it can be used anywhere and does not have to run on a server or in a lab environment.


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command line interface, visual learning systems and an easy to use graphical user

interface[7].

While Packet Tracer is sometimes used as a substitute for physical equipment, the Cisco

Packet Tracer Datasheet warns that Packet Tracer should never be used to replace physical

equipment[25].

The verbatim quotation from the Packet Tracer Cisco Data Sheet reflects this:-

“Packet Tracer supplements physical equipment in the classroom by

allowing students to create a network with an almost unlimited number of

devices, encouraging practice, discovery, and troubleshooting…” (Cisco

Packet Tracer Data Sheet, emphasis added, p. 1)[25]

A similar quotation in the same data sheet confirms that Packet Tracer is not

designed to replace physical equipment.

“… Although Packet Tracer is not a substitute for real equipment, it

allows students to practice using a command-line interface…” (Packet

Tracer Data Sheet, emphasis added, p. 2)[25]

Despite this, the Cisco Packet Tracer Data Sheet does provide some perceived benefits of

using Packet Tracer, for instance, its ability to use an (almost) unlimited number of devices

for troubleshooting, practice and discovery [25].


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According to a survey undertaken by Mohd Syahrizad Elias and Ahmad Zamzuri Mohamad

Ali, an interviewed senior lecturer who teaches networking at the Malaysian Polytechnic

Institutions was quoted as saying:-

“Students have fun doing the PT Simulation as compared to using the

actual equipment. The former helps in terms of starting the configuration,

but it gets more and more difficult when they reach higher concept levels.

The actual equipment has a better reputation in making students

understand. If they follow the lab sheet they should be able to demonstrate

the effectiveness of the PT simulation through a lot of practices, but they

are not able to do their own troubleshooting. They prefer to ask their

friends or lecturer, rather than thinking about ways to resolve the issue at

hand. The flaw of the PT Simulation is actually very scarce. I think this

issue is more apparent in certain topics like routing protocol, where the

students find it hard to apply what they have learned. ” (Polytechnic

Lecturer 5: CCNA, Senior Lecturer quoted in study in ‘Survey on the

Challenges Faced by the Lecturers in Using Packet Tracer Simulation in

Computer Networking Course’, pp. 13, emphasis added)[6]

Similar views were expressed by other quoted lecturers in the study [6]. It is also mentioned

in the paper, ‘Using a network simulation tool to engage students in active learning enhances

their understanding of complex data communications concepts’ that use of Packet Tracer

alone provides no demonstrated proof that learning is improved, questioning the premise that

the visualisation tools aid in understanding and learning. The paper does, however,

demonstrate that if Packet Tracer is used to encourage deep thinking and learning, then the


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tool is effective and useful[17]. Assistant Professor at R.K University, India, Sheikh Raashid

Javid has different views, arguing in his paper, ‘The Role of Packet Tracer in learning

computer networks’ that Packet Tracer is necessary for learning computer networks because

it provides; assessment of student activities, visualisation features designed to improve the

learning of students[8] and a cost-effective supplement to physical equipment[8]. Similarly,

the paper, ‘Visual Learning Tools for Teaching/Learning Computer Networks: Cisco

Networking Academy and Packet Tracer’, also supports the premise that Packet Tracer

provides necessary visualisation tools that are required to understand the complex

networking concepts that are not visible on a physical network [7] [24]. Both these papers

recommend the use of Packet Tracer as a supplement to physical equipment and not as a

replacement [7] [8].


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The author took a screenshot of the Packet Tracer user interface. The screenshot provides an

illustration of the visualisation tools in action.

Figure 1 Packet Tracer UI - Simulation Mode

The red cross on the blue envelope indicates a ping failure and the point in the network

where the failure occurred.


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In the survey in the paper titled, ‘Survey on the Challenges Faced by the Lecturers in Using

Packet Tracer Simulation in Computer Networking Course’, the general consensus among

the interviewed lecturers was that Packet Tracer suffices when basic concepts and topologies

are being simulated. But as more advanced concepts are introduced into the course, the labs

become much more difficult when done using Packet Tracer[6]. As outlined in the paper, ‘A

practical study on networking equipment emulation’, a simulation (including Packet Tracer)

is an incomplete model of the real thing and has limited functionality[18]. A number of

commands used on real Cisco equipment do not work properly or at all in Packet Tracer.


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To demonstrate this, the author of this thesis took a still snapshot of the Packet Tracer

interface.

Figure 2 Packet Tracer CLI - No Debug Command

This command, while a valid command on Cisco enterprise routers and switches does not

work on Packet Tracer. As you see in the image above, the command line displays the text,

‘Invalid input detected at ‘^’ marker.’ This indicates that the command, ‘debug dhcp detail’

is not a valid command. This is because this command is not available on Packet Tracer.

Because Packet Tracer has a limited subset of all the Cisco IOS commands, some education

institutions have used an alternative solution, GNS3, to simulate networking using software

virtualisation [9] [26].


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In addition to the technical limitations of Packet Tracer, some studies have indicated a

perception among lecturers that use of Packet Tracer, while fun and convenient for students,

may lead to bad study habits, such as blindly following the steps on the lab sheet, rote-

learning and a failure to apply the material or troubleshooting advanced networking

problems[6]. However, in the same study, one lecturer perceived no difference between a

student using Packet Tracer and using real equipment:-

“There has been no remarkable difference between students’ use of the

PT simulation and the actual equipment. Laboratory activities can be

done well by making reference to the lab sheet provided. Only a number of

students have problems in doing the Skills Test, where they can only do it

if they are helped, in some way. They are able to apply theories and lab

activities but stumble when it comes to perform the troubleshooting; if they

have problems, then normally the problems will be resolved with the

lecturer’s assistance.” (Polytechnic Lecturer 4: CCNA, Senior Lecturer

quoted in study in ‘Survey on the Challenges Faced by the Lecturers in

Using Packet Tracer Simulation in Computer Networking Course’, pp. 13,

emphasis added)[6]

It is clear that there is a perception that using physical equipment is preferred to simulation

tools such as Packet Tracer[6] [9] [5]. One study suggests lack of exposure to the physical

technology may result in learning difficulties in the future and subsequently lead to a lack of

confidence with using physical hardware in the industry[4]. Use of simulation tools also

requires for the learner to have some contextual background of the topic to understand the

concepts. This involves imagination to understand what is really happening[6]. Students who


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do not have this background may fail to learn anything from the tool[4]. A study by

Armstrong, H and Murray, I at Curtain University, Perth, Australia outlines the challenges

vision-impaired or blind people have with learning information technology courses. In

particular, the research found that Packet Tracer is not usable by vision-impaired students.

Consequently, its visualisation tools are useless [10]. Recent versions of Packet Tracer have

limited screen reader support, but the design of the application fails to address the issues

mentioned in the paper.


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2.2.3 GNS3

GNS3 is network emulation software widely used as a supplementary tool for teaching

advanced networking concepts. It uses the Dynamips emulator to emulate a selected number

of Cisco devices. Dynamips was originally developed by Christophe Fillot [24]. The

advantages of using GNS3 are firstly that it is an open-source project [9] [24] . This means

that it can be used at no cost. Secondly, unlike simulators, GNS3 emulates the Cisco IOS,

creating a complete replication of the functionality of Cisco devices, enhancing realism [9]

[24]. This also enables GNS3 to connect to a physical network, to other virtual machines and

to the host computer, allowing the use of real networking tools like Wireshark or ZenMap to

be used for a full simulation experience [9]. Thirdly, GNS3 runs on a home computer and is

an ideal supplement for students working remotely, or for supporting long-distance education

[9] [20]. Fourthly, all commands available on real equipment is available in the emulated

environment because an actual operating system is being emulated. Fifthly, GNS3 can share

the resources of multiple computers to enhance performance and to support many virtual

routers [24].

Several disadvantages or problems arise when using GNS3. Firstly, it can only emulate select

Cisco devices [24]. The Cisco catalyst switches are not included. Therefore, a student cannot

use GNS3 to learn switching concepts such as spanning-tree or VLANs. This eliminates

almost a quarter of the CCNA curriculum. Secondly, GNS3 is very poor in terms of

performance and requires a lot of hardware resources [24]. However, in the paper titled,

‘Comparison between physical devices and simulator software for Cisco network technology

teaching’, the author suggests that most modern computer should be powerful enough to run

it and that distribution between machines can be used, if necessary [24].


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Thirdly, while GNS3 is open source and free, the software requires a valid Cisco IOS image.

Without it, the software itself is useless. Because of licensing restrictions, GNS3 is

prohibited from including an IOS image with the software. It is also possible that even if a

student has authorisation to download and use a Cisco IOS image, the Cisco licensing

agreement restricts how that image might be used. A quotation of a portion of the software

license agreement implies that it may not be lawful to use the Cisco IOS image with GNS3:-

“… Cisco Systems, Inc. ("Cisco") and its suppliers grant to Customer

("Customer") a nonexclusive and nontransferable license to use the Cisco

software ("Software") in object code form solely on a single central

processing unit owned or leased by Customer or otherwise embedded in

equipment provided by Cisco.” (Cisco Software Licence Agreement, pp. 1,

emphasis added)[27]

It is important to note that Cisco only grants a 'non-exclusive and non-transferrable’ license.

This means that Cisco control how the Cisco IOS is to be used, and it is clear from the text

that the image is not be transferred to someone else, may only be used on customer owned

computers or on Cisco equipment with the software already embedded. There is no

authorisation that permits the use of the software in emulation platforms. Whether or not, the

use of the Cisco IOS with GNS3 is lawful or not is currently a grey area. A discussion of the

issue at The Cisco Learning Network online forums indicated that various people were

divided over the issue [28]. This uncertainty on the legality of using the Cisco IOS with

GNS3 indicates that GNS3 is not a viable alternative to Packet Tracer and/or physical

equipment due to the risk of being sued or prosecuted.


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2.2.5 Common Open Research Emulator (CORE)

The Common Open Research Emulator (CORE) is a freely-available, open-source network

simulator and emulator [19]. According to the paper, ‘Comparison of CORE network

emulation platforms’, CORE is unique in that it is considered both an emulator and

simulator. The software emulates the OSPF, OSPFv3 and BGP routing protocols using a

form of process isolation [19] [29]. Layer-2 protocols are simulated in software and CORE

uses the hardware resources of the operating system to process the network traffic [19]. This

means that CORE may run on low, inexpensive hardware.

Like Packet Tracer, CORE uses a drag and drop graphical user interface where virtual

network devices such as routers and switches are dragged onto the main pane and then

connected using virtual cables.


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The author took a screenshot of the core graphical user interface as a demonstration of what

it looks like:-

Figure 3 CORE GUI - No Nodes Added

CORE also simulates wireless networks, a feature that is commonly unavailable in many

simulation platforms [29] [19]. Unlike Packet Tracer, CORE can also physically connect to a

real network, but a separate network interface has to be reserved for CORE as it is

unavailable for use by the host system [29].

Internally, CORE runs an open-source routing engine called Quagga to provide the router

nodes with the ability to route packets using static routes or select dynamic routing protocols

such as BGP or OSPF [19] [29]. CORE can also use other simulators such as NS by using


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configurable Python scripting to enhance the functionality of the software [19]. The research

paper emphasises that CORE is ideal for scalability, supporting many nodes and has the

ability for nodes to be distributed across one or more physical machines [19]. Though, the

documentation suggests is that because the nodes are a simulation, the performance of CORE

depends on the amount of traffic being sent or received through it and not the number of

nodes [29]. In an educational environment, the amount of network traffic transmitted in a lab

is very low [18]. CORE is beneficial of helping students draw and understand network

topologies, routing configuration and operation and operation of the IP/TCP stack. The

problem with CORE is that it does not use Cisco devices. Even though the command line for

the routers is very similar to the Cisco IOS, it is not identical. Because EIGRP is a Cisco-

propriety routing protocol, CORE does not support it. A managed switch cannot be setup in

CORE unless CORE is physically connected to an external network where a real (or

virtualised) Cisco switch is installed. Therefore, although CORE has some beneficial

features, it lacks the support for Cisco devices and, therefore, is unlikely to help students

learn networking. Functionality and modelling requires programming knowledge of Python,

resulting in CORE being somewhat complex and not suitable for learning networking

courses [5]. The other problem with CORE is that it may only run on Linux or FreeBSD. It

does not run on Windows [29]. X11 forwarding can be used to access the graphical user

interface running on a remote server, allowing Windows users to use the software [29].

There has been little research on evaluating CORE for use in an academic environment.

Therefore, its effectiveness on student learning outcomes is unclear. Nevertheless, its lack of

support for switching or Cisco devices indicates that it is probably not the most suitable

solution. Interestingly, CORE can be installed on a Cisco VIRL server since the VIRL sever

runs Ubuntu 14.04 LTS, which CORE will run on [29].


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2.2.6 Miscellaneous Platforms

This section outlines and presents previous research on numerous simulation tools.

2.2.6.1 List of Miscellaneous Simulators

Some examples include:-

NetSims – Used to teach CCNA

iNetSim – An accessibility network simulation tool [10].

2.2.6.2 The Role of Network Simulators

According to the paper, ‘Simulation Tool for Active Learning of Introductory Computer

Networks’, various simulators exist for simulating networks including; Emulab, PlanetLab,

Open Network Lab and IREEL. These simulators often need to be connected to physical

equipment to work effectively and, therefore, are not suitable for use in a training

environment. Similar simulators, such as opnet, ns2, ns3, glomosim, OMMNet++ are

designed for researching network behaviour, rather than device configuration and

troubleshooting. These simulators are also complex because they require extensive

programming knowledge to simulate the network and are not user-friendly [30].

One of the important aspects of learning networking is the use of tools such as Wireshark to

learn and troubleshoot networks [9]. Third-party simulators, cnet and the scale simulation

framework lack the ability to be used with Wireshark.

Boston NetSim is a Windows-based network simulator that, according to K. Wan Mohd

Ghazali and R. Hassan, simulates more functionality than Cisco Packet Tracer. However, the

full version of the software must be purchased at a cost and is not freely provided to students.

This simulator also includes exercises to assist the student with their studies. Unlike both

Packet Tracer and GNS3, Boston NetSims is a Windows application and will not run natively


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on Linux systems4. The paper, ‘Simulation Tool for Active Learning of Introductory

Computer Networks’ recommends GNS3 and Packet Tracer and implies that these

simulatiors are preferred to the Boston NetSims simulator [30].

Therefore, none of these simulator tools are viable to be used by students for learning

networking because they do not help improve understanding of networking but are more

designed for research purposes [30].

4 It is unclear if it works with Wine / PlayOnLinux. However, this increases the level of difficulty and time

wasted.


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2.2.7 Cisco Virtual Internet Routing Lab

Cisco Virtual Internet Routing Lab (VIRL) is a software tool that simulates computer

networks. Its primary use case, according to the vendor documentation, is to test network

designs prior to the design being rolled out on a real network. Nevertheless, the design of

VIRL is not unlike a simulator which students could potentially use to learn advanced

networking concepts. Virtualisation technologies enable resources to be shared, but

virtualisation of propriety cisco equipment was difficult. GNS3 lacked support for layer-2

switching capabilities, so its application in learning environments was limited. Cisco VIRL

now supports layer-2 switching [1].

The user interface for Cisco VIRL is below. The screenshot was taken by the author on a

Mac computer.

Figure 4 Cisco VIRL Pane


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In many ways, the interface is similar to Packet Tracer because devices such as routers and

switches can be dragged and dropped onto the main pane and connected using virtual cables

as shown in the figure[2].

Like GNS3, the operating system powering the Cisco devices is virtualised and from the user

perspective appears to be real. In fact, the VIRL topology can be branched out and connected

to a real network[1]. In theory, this means students could use SSH to connect to routers and

switches using a real computer in the lab via the VIRL network.

Cisco VIRL can also support the aims mentioned in the literature. For instance, Cisco VIRL,

by design, can support both a centralised and decentralised lab. This is because routers and

switches created in VIRL can be branched out to an external layer-2 or external layer-3

network [2]. Cisco VIRL is designed to be integrated into a virtualisation infrastructure

powered using VMWare vSphere, though this requires additional configuration [2].

Subsequently, this allows VIRL to be used to set up a laboratory-as-a-service [2] [3].

Because it is running in a cloud environment, this means that VIRL can potentially be used

as a software-cloud service and hosted externally, eliminating the need to maintain physical

servers. Cisco VIRL is powered by OpenStack, the Linux KVM hypervisor and Ubuntu

14.04 LTS, allowing further customisation of the server to support the learning needs of

students. Also, Cisco VIRL replicates all the functionality and commands of physical

equipment.


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To demonstrate this, the author took a screenshot of the VIRL output.

Figure 5 Cisco VIRL - DHCP Debug Command

The output is DHCP client activity debugging is on (detailed)

The command completes successfully.


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However, on Packet Tracer, the command fails.

Figure 6 Debug Command Fails (Packet Tracer)


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There are some drawbacks with using Cisco VIRL. Some of these will be explored further as

part of the research of this paper. Firstly, the maintenance and cost of setting up the hardware

to host the Cisco VIRL server, though this can be overcome using cloud computing [1] [2]

[3]. Secondly, running a virtual network (known as a ‘simulation’) requires an extensive

amount of resources. The physical hardware alone requires full-blown hardware assisted

virtualisation if VIRL is installed in a virtual environment to function [2] [31].

The recommended minimum RAM for Cisco VIRL is 8GB and 50GB of disk space, but

meeting these requirements does not guarantee VIRL will work because the amount of

computing resources needed to run VIRL depends on the number of simulations running[31].

Assuming that one simulation uses 8GB of RAM to run, a class with 25 students all running

one simulation each would require a server with 200GB of RAM.


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2.3 Summary

Learning computer networking concepts requires both understanding of abstract concepts and

experimentation. Understanding abstract concepts is easily achieved through the traditional

lecturing style of teaching. But developing a student’s experience and soft skills, such as

problem solving and teamwork, requires a hands-on practical approach. As concluded in the

study by Holvikivi, J, a practical approach is necessary to help students develop motor skills

and to apply the theoretical material. Both a theoretical and practical approach to teach

networking concepts. Unfortunately, implementing practical networking equipment costs

thousands of dollars, so is often not affordable by many education institutions. The use of

network simulators, including Packet Tracer helps solve this problem with the trade-off of

reduced functionality and realism. Hardware resources in a lab are underutilised but have to

be separate from production networks for security and safety reasons. Virtualisation

technologies allow resources to be shared but isolated from each other, reducing the overall

costs in terms of purchasing and maintenance. While virtualisation virtualises desktop and

server operating systems quite well, virtualisation of network operating systems such as those

that run on Cisco routers and switches is done very poorly. GNS3, an open source tool, only

emulates select Cisco devices excluding switches and this emulation is very demanding on

hardware resources. The Common Open Research Emulator (CORE) emulates layer-3

protocols but uses operating system resources to maximise efficiency but it accurately

simulate Cisco devices. A decentralised lab approach uses students’ home computers to

provide the hardware resources, reducing costs. Unfortunately, this requires additional work

by students to setup, adding complexity. Furthermore, the virtualisation software lacks the

capability to simulate Cisco routers and switches. Cloud computing technologies enable


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education institutions to deliver ‘Laboratory-As-A-Service’ to students using NDG NetLab

combined with vSphere. NetLab is costly and does not run on mobile devices easily.

Cisco Virtual Internet Routing Lab (VIRL) provides full virtualisation of Cisco routers and

switches, incorporating the full functionality of a Cisco networking environment. This tool

appears to incorporate the functionality that is missing or poorly implemented in the other

tools analysed and provides a promising solution to teaching networking. However, its role in

a network training environment has not been researched. Neither has the student perceptions

of this new tool been taken into consideration. As a result, this thesis aims to investigate

Cisco VIRL’s role in a network training environment by undertaking research on a number of

select staff and students at UniSA.


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3. Methodology

In this section, the methodology for the experiment will be outlined. The first subsection will

outline the current methodologies and outline why a particular methodology has been chosen

for this research. The second subsection will outline the experimental design, providing

details on the nature of the experiment, the people involved and kind of data collected during

the experiment and the implementation. This subsection will consist of a recruitment

procedures section that will outline how the participates will be chosen, an overview of the

experiment that will provide a summary of the experiment and what will be done and

implementation will provide details such as the location and how it will be implemented. The

experiment has been approved by the UniSA Ethics Committee and may proceed.

3.1 Outline of Current Research Methodologies

The research will consist of both quantitive and qualitive research methods. The form of

research will involve observational methods and evaluation methods. Both the understanding

and perceptions of the participant will need to be gathered to assess the effectiveness of the

tool. In order for the tool to be effective, it must be perceived by students as a useful tool that

helps them learn. This information will be obtained from students through a questionnaire

evaluating their perceptions of the tool. Secondly, perceptions alone do not prove that the

tool actually assisted in developing their learning[16]. Therefore, each participant will be

issued a pre-test to assess their understanding of computer networking concepts. They will

then be given a post test, testing similar concepts to see if the tool has helped them learn.

The exercises undertaken by students will require deep thinking and application of content

used in previous networking courses to help develop deep learning[16]. If deep learning is


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observed and demonstrated in the tests, then it follows that the tool assisted their learning and

is a promising tool for teaching networking.

Because assessment of theoretical knowledge does not necessarily cover all aspects of

learning, the student will be observed to see how he reacts to mistakes and how they use their

knowledge and experience and the tool to correct the mistakes.

Other forms of research includes; testing their perceptions, testing how many mistakes they

make with the tool, or testing did they complete the lab. However, these research

methodologies do not truly determine if VIRL is a good tool for education. It simply answers

the question that a student can blindly follow instructions. Furthermore, mistakes or slow

reaction times in the application does not imply poor learning or poor understanding. At the

commencement of this project, it was proposed that each student would do one lab but on

three separate platforms. This is not only a slow process but it has the tendency to create a

learning effect that can result in confirmation bias.

3.2 Experimental Design

3.2.1 Recruitment Procedures

Participants will consist of approximately 30-60 people, comprising of both students and

staff at the University of South Australia (UniSA). The students will be selected from a pool

of networking students studying the third year of an undergraduate networking degree. The

staff members will be selected from a pool of staff members that are experienced in teaching

the Cisco Networking Academy program (CNA). Because the students are studying

networking, it is anticipated that they will have some background in computer networking

and will be suitable for the study. A screening test will be unnecessary.


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To minimise possible disruption to staff and students, the experiment will be scheduled

during the students’ routine practical class and held in the practical laboratory on the UniSA

campus.

The participates will be contacted by a recruitment email sent out by the school of

Information Technology & Mathematical Sciences (ITMS) to ask them if they would like to

participate. Those that consent to the experiment will compose of the total sample size for

this experiment.


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3.2.2 Overview of the experiment

The experiment will assess the students’ and staff members learning outcomes of using a

network simulator to complete a series of practicals similar to those done by CCNA Security

students. This will be done using both quantitive and quantitative research methods to assess

the participants’ learning outcomes.

The experiment will be broken down into four sections:-

1) Each participant will complete a preliminary set of multiple choice questions

assessing their understanding of computer networks

2) Each participant will then (attempt) to complete the series of activities using the

network configuration tool. During this time, the investigator will record numerical

data in respect to their performance and this will constitute the quantitative data.

3) Each participant will then complete a series of multiple choice questions to see if the

tool has helped them develop a better understanding of networking.

4) Each participant will fill out a shot questionnaire, evaluating their perceptions of

using the tool. This will constitute the quantitive data.

This experiment has been approved by the UniSA Ethics Committee and complies with

Australian ethics regulations. Although private or personal information will not be collected

during the experiment, the participants’ desktop will be captured using video capture

software so that their activities may be observed by the researcher. All participants will be

made aware of this prior to the start of the experiment.


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5 Chapter 3

3.2.3 Implementation

The experiment will involve each participant filling out printed questionnaires as well as

using a computer to interact with the simulated networking environment. The experiment

will be held in a practical networking lab on a UniSA campus. The experiment is estimated

take between 1-2 hours. A pilot version of the experiment will be ran prior to the experiment

being undertaken to ensure that the experiment is reasonable and can be achieved in the time

allocated.

Except for technical issues, or ambiguity with the questions, the investigator will not provide

any help to any participate, since this will make it too difficult to accurately determine the

learning outcomes.

Practical activities will cover networking topics such as STP, switching, routing protocols

and basic troubleshooting.


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6 Chapter 3

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Documents

The Role of Cisco Virtual Internet Routing Lab in … Role Of Cisco Virtual Internet Routing Lab In Network Training Environments Bradley Herbert 1 Chapter 1 Contents 1. Introduction