Design of M-Learning Platform based on Cloud Computing

Transcription

1 Design of M-Learning Platform based on Cloud Computing 1 Yan Ma, 2 Lunpeng Liu, 3 Tianping Dong, 4 Anping Zhao 1, First Author College of Computer and Information Science, Chongqing Normal University, Chongqing, China, mayan@cqnu.edu.cn *2, Corresponding Author College of Computer and Information Science, Chongqing Normal University, Chongqing, China, mayan@cqnu.edu.cn 2, College of Physics and Electronic Engineering, Chongqing Normal University, Chongqing, China, liulunpeng_87@163.com 3, 4 College of Computer and Information Science, Chongqing Normal University, Chongqing, China, dongtianpingdtp@126.com Abstract With the development of computer and network technology, as well as the popularity of the various intelligent mobile terminals, M-learning as a new learning method emerges as the times require. How to help users better obtain and make full use of M-learning resources is one of the hot topics today. Through analyzed key technologies such as wireless communication network technology, virtualization technology, data storage technology, data processing technology of cloud computing, a M-learning platform based on cloud computing was designed, which can help users obtain and make use of mobile learning resources. To introduce structure layers of the platform model and proposed several mobile learning modes based on platform and figured out the broad development prospects of the platform. What s more, the platform had been fully considered the planning, deployment, security and management, operation and optimization of the platform model, which can provide an efficient, practical and good learning environment for learners to study at anytime and anywhere. Keywords: Cloud computing, M-learning, Platform, Mobile internet, Wireless communication 1. Introduction M-learning (mobile learning) is a complex which contains wireless communication, computer network, mobile terminal as well as a variety of data storage and processing [1, 2]. With the rapid development of educational information technology, M-learning has already become a new learning method, which has obvious advantages in education and teaching [3, 4]. However, various technical reasons hinders the development of M-learning, instead cloud computing can provide technical support. Then in the support of cloud computing, bottleneck problem in M-learning can be solved, which will promote the better and faster development of the M-learning [5, 6, 7]. M-learning is essentially based on wireless communication technology, the computer network and multimedia technology, uses intelligent devices, such as mobile phone, personal digital assistant, notebook computer, to carry out the interactive teaching activities, and education, science and technology information exchange conveniently and flexibly [1, 8, 9]. With the characteristics, such as taking their ease, whenever and wherever possible, away the traditional classroom condition s constraining, learners free themselves from the puzzlement of space, learn more actively [10, 11]. The purpose of the research is to develop and use the advanced learning resources, and then promote the effectiveness of learners' learning optimization [12, 13]. The present M-learning mode mainly includes two types: one is the M-learning based on the short message service; another is M- learning through wireless network and intelligent terminal [2, 14, 15]. The tools for supporting the mobile learning mainly include intelligent mobile phone, personal digital assistant, notebook computer, etc. The M-learning tools which compares to the traditional desktop computer and laptop, has the following characteristics: (1) Portability. That is the small equipment and shape, light weight and to carry easily. (2) Wireless. That is the device without connection and to exchange data directly through the wireless transmission technology. International Journal of Advancements in Computing Technology(IJACT) Volume4, Number19,October doi: /ijact.vol4.issue

2 (3) Mobility. The mobile learning tools have mobility based on the above attributes, and users make use of these functions in mobile. The Mobile Internet Services support for M-learning by some large telecommunication companies, provide learning services for users with modern wireless communication technology. Presently, 3G, as known the third generation mobile communication network technology, refers to the cellular mobile communication technology which supports high speed data transmission. And the 3G service can simultaneously transmit voice and data information, such as video phone calls, instant messaging and etc. 3G, rather than 2G, can better realize wireless roaming in global. And it processes various forms of media, such as images, music, and video etc, and various information services include the web browsing, conference calls, e-commerce and so on. It is worth noting that, the peak of download speed can reach 3.6Mbit / s. In practice, mobile Internet service, which are provided by Chinese domestic operators, reflect the mobile Internet support mobile learning [16, 17]. However, in the current mobile learning environment, there are a lot of problems, such as the lack of technical support into the teaching, the mobile terminal data processing ability is limited, and the network storage space is insufficient and so on. As a result, the promotion of mobile learning is largely limited. In this paper, through analyzed key technologies such as wireless communication network technology, virtualization technology, data storage technology, data processing technology of cloud computing, a M-learning platform based on cloud computing was designed, which can help users obtain and make use of mobile learning resources. To introduce structure layers of the platform model and proposed several mobile learning modes based on platform and figured out the broad development prospects of the platform. What s more, the platform had been fully considered the planning, deployment, security and management, operation and optimization of the platform model, which can provide an efficient, practical and good learning environment for learners to study at anytime and anywhere. 2. Proposed M-learning platform Cloud Computing is a new method of using resources on the Internet, can provide the calculation on demand for public users through heterogeneous, autonomous service on the Internet. In essence, cloud computing service is a basic public service provided through the Internet, and users can resource acquisition, storage and compute through cloud service. As shown in figure 1, Cloud computing is a producer-consumer model, cloud computing system using Ethernet and fast network will be the number of clusters are connected together, the user through the Internet for cloud computing system provides various services for data processing. Figure 1. The Network Architecture of Cloud Computing However, the development of cloud computing is not limited to the PC, along with the vigorous development of mobile Internet, cloud computing service, based on mobile phone and other mobile terminal, has emerged. As far as the twenty-ninth statistical report on Internet development in China of CNNIC published, the number of Chinese mobile phone users reached 356 million, percentage of total Internet users to 69.3%, and increased people compared with the previous year. As we can see, the use rate on people applying the mobile device is higher and higher, and the mobile Internet will 241

3 become an integral part in people's daily life, work and learning. The combination of cloud computing and mobile Internet will also become the hot IT industry in the future. To design and develop Mobile learning platform Based on cloud computing will provide an efficient, practical, good learning environment for learners to study at anytime and anywhere. One of the important wireless network technologies is wireless local area network. [6] Before the construction of the wireless communication network, the whole link calculation should be made. According to the on-site survey result, carrying out the link calculation is in order to ensure the quality of communications. The design procedure of wireless communication network is as follows: Firstly, to research the customer demand, clear network covers the objective, and analyze the object and the users number, and from exploration get the on-site environmental parameters, transmission and point resources, etc. Next, determine the wireless communication network cover methods, according to the environmental parameters for link budget, on the basis of preliminary results, to ensure the access point location and quantity. Then on the reasonable frequency planning, avoid frequency interference, striving to minimize interference. Again, based on the users' demand we should plan communication capacity. Capacity planning and frequency planning are connected and restrict between each other, ascension capacity will increase interference and reduce interference will reduce the network capacity, actually the purposes of the program is to find the global optimization combining site between the capacity and the interference. Finally, commission the actual test on wireless communication network, to optimize and adjust the network to achieve an optimal performance. Definitely, all steps are mutual, indivisible relationship, so before a project operating the design planning should be considered synthetically. Ensure budget the link cost after the deployment of the wireless communication network. Set the output power of transmitter for Pt, space path attenuation PL (d), cable and the loss of all kinds of devices Ls, antenna gain for Gt, receiving antenna gain for Gr, the receiver receive power level below the Pr available formula is: Pr Pt Gt PL( d) Ls Gr (1) According to the formula can be calculated from the receiving signal level everywhere, and then confirm AP coverage. The wireless local area network signal transmission loss is as follows. The outdoor environment using free space propagation model, the transmission path loss formula is: L 0 ( db ) lg( d ) 20lg( f ) (2) L0 is free-space transmission loss; d is transmission distance, the unit is km; f is the working frequency, the unit is GHz. Indoor wireless transmission attenuation factor model, the model loss formula is: d PL( d)[ db] PL( d0 ) 10NMF lg( ) (3) d0 where PL( d0) 20lg(4 d0 / ) (4) Generally take d0=1m, when frequency is 2.45GHz, the value is 40 db. NMF is path loss exponent based on test multi-floors. Figure 2. The Model of Cloud Computing Service 242

4 At present the three main cloud computing service models including: SAAS (software as a service), PAAS (platform as a service), IAAS (infrastructure as a service). Cloud computing as a new calculation method, has its own unique technology in data calculation, data storage, data management and programming model, etc. As shown in figure 2. IAAS layer is the foundation for cloud computing. Through the establishment of large-scale data center, IAAS layer for the upper cloud computing services provides massive hardware resources. Meanwhile, in support of virtualization technology, IAAS layer can realize on-demand configuration of hardware resources, and provide personalized infrastructure services. PAAS layer, as the middle layer of the core services, provide a simple and reliable distributed programming framework for the upper layer application, and shield the complexity of the bottom system which based on the underlying information resources scheduling operations, managing data. With the popularity of data-intensive applications and the increasing scale of large data, PAAS layer needs to have the capacity of the storage and processing massive data. SAAS layer is aim to the cloud computing end-users and provide software application services which is based on Internet. With the maturity and standardization of Web services, HTML5, Ajax, MASHUP and other technology, SAAS applications have developed rapidly in recent years. Three types services of cloud computing involved in the following specific key technologies. As described in the following table 1. Table 1. Comparison of IAAS, PAAS, SAAS Service content Service object Key technology Application Users who needed Virtualization technology, Data Amazon EC2, IAAS hardware resources management technology, etc. Eucalyptus, etc. Data processing technology, Resource Google app engine, PAAS Program developer management and scheduling technology, Hadoop, etc. etc. SAAS Enterprise or users who need software application Software application, Web services, User management, etc. Google apps, Salesforce CRM, etc As can be seen, cloud computing involves extensive technology. As far as the M-learning platform, cloud computing through the virtualization technology can achieve the optimal use of resources, can according to the change of customers' needs, distribution according to one's needs, realize the dynamic load balance. The objects of virtualization technology can range from servers, storage and network to the platform, application and other aspects. Cloud computing uses the distributed storage way to store data, its distributed architecture can let as many as one million sets of cheap computers work together, can guarantee that data store high availability, high reliability and economic efficiency of platform. Cloud data processing center processes and analyses a set of data, using the parallel computing way, with multiple processors to solve the same problems, to provide the highly effective service to users. 3. Proposed mobile learning platform model Figure 3. The M-Learning Platform based on Cloud Computing 243

5 Under support of the cloud computing, this paper designs a mobile learning platform model, as shown in figure 3. (1) The Physical Layer Under the cloud computing environment, the physical layer includes computer cluster, network interconnection apparatus, database resources, as well as all kinds of learning resource database free in network. Computer cluster only partly provides learners with super computing power, most simply provides the storage function. There are large quantities of scrap computers, which do not fit the requirement of the times for single use, but they are completely feasible as the platform of the physical layer. This not only in economy saves the costs in building cloud platform, and uses the old and useless resources rationally. In the design of this platform, the physical layer put together the dispersed computers form a cloud cluster server which provides super function, using distributed technology and virtualization technology.[8, 16, 18] Through the wireless network, the cloud can provide computing and storage service for learners. (2) Virtual Resource Layer In cloud computing, virtualization is a key technology. [9] Virtualization is a general term, in computer aspect usually refers to the computing element operate in virtual resources rather than on the basis of a real. Virtualization technology can enlarge the capacity of the hardware, simplify software configuration process again. The CPU virtualization technology can be single CPU simulation of multi-cpu parallel, allow a platform to run multiple operating systems and applications can be run in a separate space, each other is not affected. Using virtual technology can make hardware and software services, learning resources into a virtual resource pool, and the users get high performance computing, data storage space, download and application of learning resources through the network from the virtual resource layer. Virtual resource layer can improve the efficiency of the Mobile terminal for learners. (3) Resource Management Layer Resource management layer is core management layer designed by M-learning platform based on cloud computing, which is responsible for resource management on the M-learning platform. On one hand, manage task submitted by users. The task the user submitted is created to different image files and deploys to each node according system design. The layer dispatches timely according to the load status of each node in the task of processing, seals the task on the node loading much larger, and transfers to the idle or insufficient system. On the other hand, manage the system resource, including screening and upload learning resource, the user information management, and network maintenance. (4) The Application Layer The application layer provides the entrances of using various services conveniently for every learner. Through a mobile network access users can enjoy online demand, off-line download, data storage, high performance computing, application software and other services. At the same time it can use portability and other characteristics of the cloud computing platform, to provide API port for the access of other clouds server, which cannot only expand more resources and service support for the learning, but also can realize the sharing of resources between different fields. (5) The User Layer In M-learning model, the mobile equipment the user holding must be able to log in to the Web browser. According to the statistical data shows, using rate of mobile intelligent devices increases annually, the client can mainly achieve the using function of the cloud platform service. The user layer includes three modules: the interactive control module, the user evaluation module, the teacher instructs module. Cloud servers provide database for users: resource database, evaluation database, guidance database. Administrators can manage the database platform by the interactive control module; Instructors can guide the learners by the teacher instructs module, and expand mobile learning resources to resource database and guidance database by the interactive control module; Users study by the interactive control module and the teacher instructs module, evaluate the learning effect by the user evaluation module, then administrators conduct real-time updates to the cloud database according to the interaction and feedback, as shown in figure

6 Figure 4. The M-Learning Interactive Model based on The Platform (1) Personal autonomous learning mode based on learning resources. In the cloud servers, the teaching management set up mobile learning resource and mobile learning support tools for learners. M-Learning resource database includes: video live, demand, download courseware, text material and so on. In the process of moving teaching, the teacher can set up teaching question-answering system. The learners can choose the suitable way or method to go on personalized autonomous learning at their own favorite time and place. [10] For example, through the smart phones students can download learning courseware in the lawn and also can watch the video live in network coverage areas. (2) The team cooperation study mode based on network platform. In the M-Learning, learners can through team cooperation, conducted discussions to study. The participants can constitute freely according to oneself circumstance, using their different characteristics for complementary in order to achieve the best effect of learning. For example, the learners in an area can spontaneously organize up through the mobile devices to extend study or the students who join an activity at the same time can complete the course assignments altogether. (3) The virtual community mobile learning mode. In M-learning platform based on cloud computing is helpful for the integration of the huge teaching resources in the network and providing a virtual learning community for mobile learners. In virtual learning environment, learners do not need to know the true identity learning companions, and they can participate in mobile learning freely. The learners can freely express their views, taking advantage of the time gap in life, and enhance the learning initiative. More importantly, cloud servers can continually up-grade hardware and storage space that can provides a basic guarantee for teaching managers to set up the capacity of super learning resource, offers a strong support to develop various teaching activities for teachers in the virtual community. Due to the openness of physical media, mobile learning platform will face more security issues. We need to pay attention to the following questions. In link layer of wireless network [11], we need to consider the combination of 802.1x authentication and guard against common attacks for packets such as Flood, Null Data and Weak IV. At present i security mechanism was used extensively in the security standards and China WAPI safety standards have gradually mature, the requirements of the mobile learning platform for data transmission will be met. The management of this platform using wireless management system dynamically manages the user IP, MAC address, user name, AP and the security policies. Furthermore, to realize the good management of the user, it can rapidly query each user's information and records in the system. Mobile learning platform based on cloud computing is helpful for personnel training in universities, enterprises and government [17], and it's also helpful for the whole society realizing of lifelong learning. There are enormous business opportunities in the telecommunications industry. Major communications service providers are committed to the transformation of their respective platforms for potential customers to develop new mobile cloud computing services program. [12, 18] Operators will accelerate the deployment of large-scale mobile network infrastructure, expand the mobile network bandwidth and reduce the flow of mobile devices use fee at the same time. The optimization of the platform is an ongoing process. M-learning platform needs more content support, which need to play the advantages of clouds, continuously improve the structure and content of the platform according to effect evaluation of m-learning, to design a rational m-learning environment and to develop more effective m-learning resources. [13] 245

7 Instructors can use the following method to evaluate learners mobile learning effect. [14] For example in a class, set the number of students who use the platform to learning for n; Through the test, set the number i student s test results for X. Definition: i X n i 1 n X i (5) S n i 1 ( X X) i n 2 (6) Xi X Zi (7) S Known by the definition, S is the standard deviation of the overall results of the students. Zi reflects the difference between score and the average score of student i is several times of the standard deviation. Raw score which is tested in different times converted into standard scores, then it can be compared with each other, and evaluate the m-learning effect. For example, through using the platform to learning, in two different tests a student test scores are 90 and 80, standard scores are 2 and 2.5. It shows that the standard score of the second is higher than the first, so the student has made a progress. Otherwise, the student s performance is on the downgrade. 4. Conclusion Under the support of wireless communication technology, platform based on cloud computing as a learning supported system, has the feasibility of design and development. [15, 18] M-learning can improve the learners enthusiasm of active learning, and promote resources sharing of the whole society, having the broad development prospects. In addition, in order to realize the aim of education socialization and lifelong education, research and development the whole society M-learning mode is imperative, it needs more study concept and related technical support. To develop the platform is a systematic project, only fully considered the planning, deployment, security and management, operation and optimization of mobile network and cloud servers, can achieve the operational, manageable platform desired by the user. 5. Acknowledgement This work is sponsored by Chongqing Higher Education Educational Reform (NO: ) and Chongqing Education Committee (KJ090809) and Chongqing Natural Science Fund (KJ120617). 6. References [1] Chenglin Ye, Fuyin Xu, Ju Xu, Mobile Learning Research Overview, E-education Research, no. 3, pp , [2] Chengyun Huang, Mingzhang Zuo, Xianhai Rong, Design of Mobile Learning System Base on Cloud Computing, China Educational Technology, vol20, no. 8, pp , [3] Minghui Wang, Analysis of Hot Technologies and Applications of Mobile Internet, Business & Operation, no. 4, pp , [4] Jianhua Sun, The Future of Computing in the "Cloud" Talking about the Cloud Computing and Mobile Learning, Modern Educational Technology, vol19, no. 8, pp , [5] CHEN Quan, DENG Qianni, Cloud computing and its key techniques, Journal of Computer Applications, vol29, no9, pp , [6] Yang Shi, Modern Communication Technology and Service, Posts & Telecom Press, China,

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