The Study of Implementation and Assessment of a Cloud Computer Room. Pai-shu Huang, Shih-hao Shen. WuFeng University, Taiwan

Transcription

1 The Study of Implementation and Assessment of a Cloud Computer Room Pai-shu Huang, Shih-hao Shen 0178 WuFeng University, Taiwan The Asian Conference on Technology in the Classroom Abstract: The so-called computer laboratory has various requirements for which cover a number of different combinations of operating systems and applications. The traditional method installed more than one combination and used separate and independent partitions of the disk in a personal computer. Applications performed on a single host are almost neither high throughput nor busy. Single host does not require a lot of system resources most of the time. Hence, virtualization is a new technology evolved from the software simulator. A virtual machine operates many running instances together using aggregated resources across shared resource pools between many servers. This brings manageability benefits. Allocated an instance to a user, he can remotely control his virtual host via the RDP protocol and so on. The circumstance that the CPU, memory, and others are fairly shared to each instance not only can increase CPU usage but also can provide high-performance servers to meet the user's burst working because resources have remained capacity in the resource pool. The purpose of this study is to develop a cloud computer laboratory. After that, Davis' Technology Acceptance Model is used to evaluate our system. The corresponding questionnaire of this study has been used to collect data to analyze users' beliefs, attitude, and intentions that may impact on system operating. Key words: Cloud computing, remote desktop, Technology Acceptance Model 139

2 1. Introduction Because of the constraints of wired network, people cannot move freely on the internet and therefore set limit to the users. However, the development of today s information technology has produced many portable computing resources with wireless networking such as Tablet PCs, smart phones, etc. The qualities of portability, wireless networking, and other innovative technologies combined together have made personalized mobile offices for users. The computer learning classes make many different combinations of operating systems and applications due to the requirement of different classes. The traditional method is to install more than one combination in every personal computer. When a single application on a single host is performed, the average CPU usage is usually about 20% most of the time, meaning that the computer is under the situation of low loading or idle state. However, it is much more possible that an individual operate many applications at the same time. Therefore, we cannot choose computers with low performance. This is a dilemma between service maintenance budget and users learning efficiency as well as satisfaction. With virtualization technology, this dilemma may be solved to some extent. The virtualization technology allows a server to share resources to many users, which additionally equips a computer with access of remote control. Thus, it is necessary and enough to have a computer laboratory connected to the internet and showed the remote desktop. We can install a set of the guest operating system (guest OS) that equips with appropriate applications for each student/learner in a virtual machine. A user controls his remote desktop to connect to the virtual host in a snapshot. While in general a CPU with higher performance would cost more power consumption, operating the virtual machine can mutually share resources and save power. If we use virtualization technology, we can purchase a high-performance server and share the CPU usage to users with fair and efficiency. This not only can increase CPU usage, but the high-performance also satisfies users burst needs and operations by remaining capacity in the resource pool. An additional benefit of this method is simplification of the computer lab management and maintenance. While in the traditional method where a manager of the lab has to manage and maintain hundreds of personal computers, the manager of a cloud computer lab do the choirs only on a single server. The PC users use by connecting to the internet, and the manager only needs to manage on a Server to assign a user to one or more snapshot. The front-end computers for users only need to carry loading required for network traffic of the remote desktop and display updates. So the required resource is very low. As to the management of the device, it is not heavier than before due to reduce of re-purchase costs and maintenance costs. Our study is to build a cloud computer laboratory and assess how this method is accepted by users/computer learners. Therefore, we adopt Davis Technology Acceptance Model (TAM) (Davis et. al. 1989) to evaluate the cloud computer laboratory s acceptance. 140

3 2. Benefits of the Virtualization Technology The Virtualization technology in the computer industry is defined as a heterogeneous platform building the operational interface of software and/or hardware. In short, virtualization technology may be the machines, systems or software running on a to allow the environment they operated. Originally an environment with different operating system, diverse software, application is integrated on a single server, called a virtual machine. Integrated in a single environment to run a separate operating system, hardware resources have share such as CPU utilization, memory, and software installation and so on. In accordance with the operation of virtual machines to achieve efficient use of resources, this reduces server idle time, improving utilization and system portability. Web services are an inevitable trend based on the constant development of clientserver architecture. With the increasing various services provided by network servers, a server can share resources to many users, but the more users and services provided, the heavier the server load. Therefore, there goes cluster computing technology. Cluster computing makes a server, a single high-performance computer, dispersed into many computers which have moderate performance by mutual support on the network. In addition, it allows the clustering nodes to move toward the end users to reduce the waste of the bandwidth. Even the users move their locations in the network, they can always access to the nearest clustering resources. However, the web services nowadays still rely on server-side systems development which makes impossible to satisfy every person s needs. Hence, it is necessary for individuals to have a personalized computer to install whatever programs they need. When considering the usage of a personal computer, you will find there exist many unused computing and storage resources. Therefore, it has become the latest business model to combine virtualization technology that turns cluster computing resources into many virtual computers and put to use via the access of remote desktop. Much of the remote desktop access nowadays, however, is connected through specific applications. Whether or not the applications can be instilled in a user s computer is unknown, and this makes the feature of using the device everywhere and anytime impossible. This existing difficulty leads to our research interest. 141

4 This study has confirmed the purpose to determine the scope of the study and then proceeded with the erection of the "research platform" experiment shown in Figure 1. Figure 1. The client-server research platform 3. The Theoretical Bases for the Study The study is an action research that emphasizes the researchers intentional intervention (building a cloud computer laboratory), assessment (questionnaires based on TAM), and feedback as well as researchers reflection. The study has three stages. The first stage is to build an environment of a cloud computer laboratory which utilizes virtualization technology. The second stage is to allow the users (participants) to operate under this environment. The last stage is to collect the users beliefs, attitude, and the intention of use by a questionnaire developed based on TAM, as Figure 2. Figure 2. the Davis Technology Acceptance Model TAM developed and modified according to the theory of rational behavior. This model is quite useful in understanding individuals usage regarding to information technology. The model has two important constructs as follows: 1. Perceived usefulness (PU): meaning that a user subjectively thinks of the technology in terms of its use to work and the future. 2. Perceived ease of use (PEOU): meaning a user s perceived degree of the ease of use of the technology. In this model, we take into consideration users grades (age), gender, and computer capacity as the background factors. 142

5 4. The implementation process Implementing a cloud computer laboratory may be beneficial to between students, teachers, and technicians. User's satisfaction, involvement, and participation may assess the influences. We have three stages to lead users to involve this system as follow. 4.1 The first stage: building a cloud computer laboratory Instance App. App. App. Guest O.S. (Linux) Guest O.S. (Windows) Guest O.S. Virtual Machine (XenServer) Hardware Figure 3. different operating systems and applications set on the virtual machine. First, we constructed the back-end servers and virtual machines on the server architecture. Many of the images of the installed operating system and applications set on the virtual machine, shown in Figure 3. The overall resources can save more, and managers are also better able to facilitate the processing of error and exception occurs. Image files on the virtual machine will be equipped with the need to start, as an instance. The remote desktop server, a program, runs on each instance. The student's computer is the RDP client. That is using the remote desktop users. The entire installation is complete, so that both ends can connect and operate. Back-end server is not only set up a virtual machine, but with many instances of running. Hence that different users do choose to belong to the "desktop" in accordance with the "identity conditions" different The second stage: helping users learn and operate under the environment of the cloud computer laboratory After building the cloud computer laboratory, students taking relevant computer classes were introduced to the cloud computer laboratory and its technology, and were asked to learn how to use the remote desktop to enhance self-learning and extracurriculum practice. Our study included three classes and about 105 participants. These students took part in this stage for about 18 weeks (one semester) The third stage: assessing the acceptance of the cloud computer laboratory through a questionnaire based on Technology Acceptance Model The last stage is to assess the cloud computer lab s acceptance. Therefore, we adopted TAM shown in the following to develop a questionnaire. This is an on-line questionnaire that is made by Google Documents. We save it in as Figure

6 Figure 4. Our on-line questionnaire. 5. Result and Discussion 5.1. The Assessment We developed a questionnaire according to Lee et al.(2003) and Ajezn(1989) to collect primary data. This questionnaire aimed at understanding participants experiences of using remote desktops on virtual computers. Background questions were included such as subjects grades(q1), sex(q2), and computer ability(q3 to Q6). The questionnaire used Likert scale to measure users experiences in terms of 144

7 perceived usefulness(q17-q24), ease of use(q9-q16), attitude(q25-q32), as well as their usage(q7-q8) (scale scores from 1 meaning very much disagree to 6 representing very much agree). In order to understand the psychometrics of the questionnaire, 105 junior college students were asked to participate in the pre-test. In the pre-test study, we assessed the consistency and validity of the questionnaire. We first conducted item analysis and confirmatory factor analysis (CFA). The intention of the pre-test is to modify the questionnaire to put through further testing Item Analysis The item analysis by SPSS 15.0 shows pretty good result that all items have achieved.70 factor loading. Thus we did not delete any item in this process. e18 e e20 e err1 grade Q18 Q19 Q perceived usefulness.51 Q err e3 Q3.75 e4.60 Q4 sex computer ability e5 Q e6 Q6.25 err perceived ease of use Q12 Q13 Q e12 e13 e Q15 e28 e15.57 Q28 behavioral use attitude Q29 Q30 Q e29 e30 e31 Q32 e32 err3.43 TAM model chi-square= degree of freedom=159; p-value=.000 gfi=.700; agfi=.604 rmsea=.124 Figure 5. The structural equation modeling of this study. 145

8 5.3. The confirmatory analysis of the pre-test The confirmatory factor analysis used structural equation modeling via AMOS 7.0 software to evaluate the measurement and structural models, as Figure 5. Items would be considered to delete if they meet the following situations: (a) the item s factor loading gets lower than.30 (Hair, Anderson, Tatham, & Black, 1998); (b) the internal consistency (Cronback s α) gets higher after deleting the item; (c) the item-tototal corrected correlation of the item is low; (d) the squared multiple correlation coefficients (SMC) is lower than.40 (Taylor & Todd, 1995). In addition, the deletion of any items should still take into consideration the suggestions of the theory (TAM) to maintain or modify the item. The goodness of fit statistics included chi-square(χ 2 ), goodness-of-fit index(gfi & AGFI), root mean square error of approximation (RMSEA)(Bagozzi & Yi, 1988). The result of the pre-test showed that some items of the questionnaire should be deleted. Items should be deleted including: four items representing perceived ease of use (Q9, Q10, Q11, and Q16), four items representing perceived usefulness (Q17, Q21, Q23, and Q24), three items representing attitude (Q25, Q26, and Q27), as well as one item representing usage (Q7). However, even deleting these items, the structure model still showed poor match between the items and observation data. 6. Conclusion: the researchers reflection Researchers reflection are that the reflection on the intervention; during the implementation stage, the researcher as a teacher did see the advantage of the virtualization technology in terms of computer laboratory management. However, the researcher as a teacher did not feel participants preference over this method during the semester. Therefore, it is important for the future study to take into consideration some factors such as students acceptance of innovative technology, the possibility of daily use of the technology, and the friendliness of the innovative technology. Reflection from the development and feedback of the questionnaire; the result of the pre-test of the questionnaire shows that the items do not properly match what we intended to assess. Hence, it is necessary to go back to the item generation process and modification in order to produce a questionnaire that is more suitable for our research intention. We are still on the way toward implementing a cloud computer environment which is friendlier and preferable and assessing the acceptance of virtualization technology. 146

9 References DAVIS, F.; BAGOZZI, R., and WARSHAW, R.,1989. User Acceptance of Computer Technology: A Comparison of Two Theoretical Models. Management Science, Volume 35, 1989, pp LEE, Y., KOZAR, K. A., and LARSEN, K. R. T., The Technology Acceptance Model: Past, Present, and Future. Communications of the AIS, Volume 12, 2003, pp AJZEN, I., Attitude Structure and Behavior. In A. R. Pratkanis, S. J. Beckler, & A. G. Greenwald (Eds.), Attitude Structure and Function, 1989, pp Hillsdale, NJ: Lawrence Erlbaum. HAIR, J. F., ANDERSON, R. E., TATHAM, R. L., and BLACK, W. C., Multivariate Data Analysis, 1998, P Englewood Cliffs, NJ: Prentice Hall. TAYLOR, S., and TODD, P., An Integrated Model of Waste Managient Behavior: A Test of Household Recycling and Composting Intentions. Environment and Behavior, Volume 27, 1995, pp BAGOZZI, R. P., & YI, T On the Evaluation of Structural Equation Models. Journal of the Academy of Marketing Science, Volume 16, 1988, pp

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