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5.5 APROXIMACIONES TEORICAS AL TRATAMIENTO DEL TAMBO DE RUELAS

El Tambo de Ruelas como posibilidad

5.5 APROXIMACIONES TEORICAS AL TRATAMIENTO DEL TAMBO DE RUELAS

WiFiVL II was evaluated with students in

BSc in Computer Science at the University of St Andrews. The evaluation detailed here took place during a laboratory session for CS3102 in

802.11 protocols and utilised the WiFiVL II for exploratory learning. a worksheet that was used in previous laboratory

Appendix 1.4 was provided to students as a guide to the new user interface. During the laboratory session,

class. The majority of attacks were a type denial of service attack consisted

to tie up the simulator resource. The resulting output from WiFiVL II including graph g XML result construction, streaming to the RIA, event set

within usability guidelines for response time of systems the URL providing invalid parameters to the WiFiVLServlet. Students were also interested

WiFiVL II. Many students’ experiments involved varying receiver strengths and different routing protocols. Whilst most of the routing protocols were unfamiliar to th

online resources such as Google, Wikipedia and the WiFiVL I host site.

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Chart showing the distribution of packet types. This is an example of the chart that is configured scenario in WiFiVL and shows how students can alter variables in

the simulation to derive different statistical results

An example output is shown in Figure 52 and sample usage by students in 5.7.3.

Supervised Evaluation Sessions for WiFiVL II

n several laboratory sessions for both undergraduate and postgraduate students. This sessions where the students provided evaluation data.

Supervised Laboratory Session of WiFiVL II

evaluated with students in a 3rd year module (CS3102) delivered as part of the degree BSc in Computer Science at the University of St Andrews. The evaluation detailed here took place during a laboratory session for CS3102 in May 2008. The laboratory session focused on the IEEE 11 protocols and utilised the WiFiVL II for exploratory learning. The students were provided with a worksheet that was used in previous laboratory sessions involving WiFiVL I.

was provided to students as a guide to the new user interface.

malicious attacks were consistently crafted by a large proportion of the class. The majority of attacks were a type of denial of service through large simulation requests. Each ed of adding many nodes and frequent, large data transfers in an attempt to tie up the simulator resource. The resulting output from WiFiVL II including graph g

XML result construction, streaming to the RIA, event set-up and playback in the RIA was consistently within usability guidelines for response time of systems [266]. Other attacks consisted of modifying the URL providing invalid parameters to the WiFiVLServlet.

in the various routing protocols that were exposed to them through WiFiVL II. Many students’ experiments involved varying receiver strengths and different routing protocols. Whilst most of the routing protocols were unfamiliar to them, research was performed using online resources such as Google, Wikipedia and the WiFiVL I host site.

This is an example of the chart that is configured scenario in WiFiVL and shows how students can alter variables in

n several laboratory sessions for both undergraduate and postgraduate students. This

3rd year module (CS3102) delivered as part of the degree BSc in Computer Science at the University of St Andrews. The evaluation detailed here took place May 2008. The laboratory session focused on the IEEE The students were provided with sessions involving WiFiVL I. The document in

malicious attacks were consistently crafted by a large proportion of the of denial of service through large simulation requests. Each of adding many nodes and frequent, large data transfers in an attempt to tie up the simulator resource. The resulting output from WiFiVL II including graph generation, up and playback in the RIA was consistently . Other attacks consisted of modifying

in the various routing protocols that were exposed to them through WiFiVL II. Many students’ experiments involved varying receiver strengths and different routing em, research was performed using

The students easily constructed scenarios with increasing complexity and showed great interest in the protocols and software. Such complexity in simula

interface available was the HTML form.

The WiFiVL II question only occupies a quarter of the worksheet but became the focal point of the laboratory session. The students were keen to experiment with the s

the scheduled one hour session and continuing to provide informal feedback and creating new scenarios.

Figure 53: SUS and educational value in a laboratory session using the WiFiVL II was 61% and average educational value was 70%

Figure 53 shows a positive reaction to the use of WiFiVL II with a third of the responses giving a high educational value and usability rating of 71

5.7.2

Supervised Laboratory Session

WiFiVL II was evaluated with students in postgraduate module

degree MSc in Advanced Computer Science at the University of St Andrews. The evaluation detailed here took place during a laboratory session for CS

The students were provided with the worksheet shown in stress test the system by the students.

observe the system over an extended period. The number of requests is shown in system remained stable, with no crashes or service

time. 0 10 20 30 40 0 - 10 11 - 2021 P e rc e n ta g e o f re sp o n se

s System Usability Scale Educational Value

95

The students easily constructed scenarios with increasing complexity and showed great interest in the protocols and software. Such complexity in simulations had not been seen in WiFiVL I where the only interface available was the HTML form.

The WiFiVL II question only occupies a quarter of the worksheet but became the focal point of the laboratory session. The students were keen to experiment with the software with most staying beyond the scheduled one hour session and continuing to provide informal feedback and creating new

and educational value in a laboratory session using the WiFiVL II. SUS aver was 61% and average educational value was 70%

shows a positive reaction to the use of WiFiVL II with a third of the responses giving a high educational value and usability rating of 71-80%.

Supervised Laboratory Session of WiFiVL II

as evaluated with students in postgraduate module (CS5109) delivered as part of the Computer Science at the University of St Andrews. The evaluation detailed here took place during a laboratory session for CS5109 in November 2008.

The students were provided with the worksheet shown in Appendix 1.8. There were limited attempts to stress test the system by the students. This practical ran for a week, which presented an opportuni observe the system over an extended period. The number of requests is shown in

with no crashes or service interruptions, and provided no decrease in response 21 - 30 31 - 40

41 - 50 51 - 60

61 - 70 71 - 80 81 - 90 User Rating

System Usability Scale Educational Value

The students easily constructed scenarios with increasing complexity and showed great interest in the tions had not been seen in WiFiVL I where the only

The WiFiVL II question only occupies a quarter of the worksheet but became the focal point of the oftware with most staying beyond the scheduled one hour session and continuing to provide informal feedback and creating new

. SUS average score

shows a positive reaction to the use of WiFiVL II with a third of the responses giving a high

) delivered as part of the Computer Science at the University of St Andrews. The evaluation detailed

. There were limited attempts to which presented an opportunity to observe the system over an extended period. The number of requests is shown in Figure 54. The and provided no decrease in response

90 91 - 100

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Figure 54: Usage of WiFiVL II over the week preceding a laboratory submission date of 2359 on 11/11/2008

A key success of the practical was the ability to use either a form or a point and click interface on the same system, allowing the student to choose the most suitable interface for their needs. The laboratory session also tested the ability of the statistics generation components of the system. The worksheet required an exploratory approach to learning in order to explain the changes generated in the graphs. One area for exploration was to investigate whether an increase or decrease in dropped packets occurred depending on the use of RTS/CTS signals.

0 50 100 150 200 250 300 350 400

Number of requests per day

Number of requests per day

The students were provided wi

Usability Scale (SUS) Likert scale for describing the interfaces available to them. Another evaluation sheet was provided to assess the

strongly encouraging and are summarised of the system and the maintenance of a high d for educational value is shown in

education of the IEEE 802.11 protocols by the students. The question numbers can be found in Appendix 1.6.

Figure 55: Distribution of SUS and educational value questionnaire 0 20 40 60 0 - 10 11 - 20 21 30 P e rc e n ta g e o f re sp o n se s User rating 0 - 10 System Usability Scale 0.0 Educational Value 0.0

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The students were provided with evaluation sheets. The evaluation sheets took the form of a System Usability Scale (SUS) Likert scale for describing the interfaces available to them. Another evaluation sheet was provided to assess the perceived educational value of using the system.

and are summarised in Figure 55. These results show an increase in the usability of the system and the maintenance of a high degree of educational consideration. The average rating for educational value is shown in Figure 56 and shows that WiFiVL II is seen as helpful in the education of the IEEE 802.11 protocols by the students. The question numbers can be found in

istribution of SUS and educational value questionnaire. Average score for SUS was 66% and for educational value 79%

21 - 30 31 - 40 41 -50 51 - 60 61 -70 71 - 80 81 -90 User rating 10 11 - 20 21 - 30 31 - 40 41 - 50 51 - 60 61 - 70 71 - 0.0 0.0 0.0 0.0 18.2 36.4 9.1 9.1 0.0 0.0 0.0 0.0 0.0 8.3 8.3 58.3

th evaluation sheets. The evaluation sheets took the form of a System Usability Scale (SUS) Likert scale for describing the interfaces available to them. Another evaluation The results were . These results show an increase in the usability The average rating and shows that WiFiVL II is seen as helpful in the education of the IEEE 802.11 protocols by the students. The question numbers can be found in

. Average score for SUS was 66% 91 - 100 80 81 - 90 91 - 100 9.1 9.1 18.2 58.3 8.3 16.7

Figure 56: Average rating from the students on the educational aspect of WiFi