International Journal of Computer Science Research and Application 2012, Vol. 2, Issue. 1 (Special Issue), pp. 31-41 ISSN 2012-9564 (Print) ISSN 2012-9572 (Online) © Author Names. Authors retain all rights. IJCSRA has been granted the right to publish and share, Creative Commons 3.0

INTERNATIONAL JOURNAL OF COMPUTER SCIENCE RESEARCH AND APPLICATION www.ijcsra.org

Enhanced Virtual E-Learning Environments Using Cloud Computing Architectures Eugen Zaharescu ”Ovidius” University of Constanta, Romania, [email protected] Str. Cismelei nr.17, Bloc 1A, Sc. A, Ap. 32, Constanta 900482, +40770785741, [email protected]

Abstract This paper presents the essential information about the most complex software systems and platforms managing enhanced educational virtual spaces that can integrate adaptive hypermedia units, video-conference support, mobile devices, etc.. In the description of these modern e-learning technologies, their most important features are revealed, like communications across disciplines, collaboration and team capabilities based on Web infrastructure. These enhanced education services use shared cloud computing approaches or methods and provide an optimized e-learning management to generate creative and intelligent decision. The basic architectural concepts and principles are imported from grid computing and cloud computing systems (e.g. Microsoft Azure, IBM Smart Cloud, IBM Tivoli- Live Monitoring Infrastructure Services, IBM Computing on Demand (CoD)™”). World-class social networking services and online collaboration tools, including file sharing, Web conferencing, and instant messaging are described subsequently (e.g. IBM LotusLive™)”. Also, the basic concepts and principles of virtual e-learning environments for e-universities are presented, following the taxonomy: e-learning management systems (Claroline, Desire2Learn, eFront-Open-Source web-based Learning Management System, LAMS Learning Activity Management System, SharePointLMS, JoomlaLMS-Joomla platform-based LMS); open source course management systems (Moodle, Dokeos, ILIAS, Sakai); virtual e-learning environments (Sloodle-Second Life and Moodle merge, Blackboard, WebCT, FirstClass, CyberExtension); cloud computing architectures for enhanced education services (IBM Cloud Academy program).

Keywords: Cloud Computing, Enhanced E-Learning Services, E-Learning Management Systems, Intelligent Virtual E-Learning Environments.

1. Introduction Cloud computing technologies have changed the way applications are developed and accessed. They are aimed at running applications as services over the Internet on a scalable infrastructure. Many applications such as word processing, spreadsheets, presentations, databases and more can all be accessed from a web browser, while the software and files are housed in the cloud. Clouds are developed to address Internet-scale computing problems where some assumptions are different from those of the Grids. Clouds are usually referred to as a large pool of computing and/or storage resources, which can be accessed via standard protocols via an abstract interface. Clouds can be built on top of many existing protocols such as Web Services (WSDL, SOAP), and some advanced Web 2.0 technologies such as REST, RSS, AJAX, etc. In fact, behind the cover, it is possible for Clouds to be implemented over existing Grid technologies leveraging more than a decade of community efforts in standardization, security, resource management, and virtualization support. Educational institutions can take advantage of cloud applications to provide students and teachers with free or low-cost alternatives to expensive, proprietary productivity tools. Browser-based applications are also accessible with a variety of computer and even mobile platforms, making these tools available anywhere the

32

International Journal of Computer Science Research and Application, 2(1):31-41

Internet can be accessed. This paper presents a cloud computing based solution for building a virtual and personal learning environment which combines a wide range of technology, and tools to create an interactive tool for science education. The system allows exchange of educational content and integrate different pedagogical approaches to learning and teaching under the same environment.

2. Defining Cloud Computing Paradigm The major players in the field of Cloud Computing are Google, Microsoft, Amazon, Yahoo, IBM and Intel. Cloud Computing applications are mainly intended to help companies and individuals to stretch resources and work smarter by moving everything to the cloud. One of the biggest promoters of the cloud computing is Google that already owns a massive computer infrastructure (the cloud) where millions of people are connecting to. Today, the Google cloud can be accessed by Google Apps intended to be software as a service suite dedicated to information sharing and security. Google Apps covers the following three main areas: messaging (Gmail, Calendar and Google Talk), collaboration (Google Docs, Video and Sites) and security (email security, encryption and archiving). Microsoft is developing a new Windows platform, called Windows Azure, which will be able to run cloud based applications. Amazon extended its AWS (Amazon Web Services) suite with a new component called Amazon Elastic Compute Cloud (or EC2), that allows to the users to rent from Amazon processing power to be used to run their own applications. The EC2 users rent out from Amazon virtual machines that can be accessed remotely. The cloud is an elastic one just because the user can start, stop and create the virtual machines through the web service. There are three predefines sizes for the virtual machines that can be rented: small, medium and large, depending on the physical hardware performances. One of the many possible definitions for Cloud Computing may be the following: Cloud Computing is a large-scale distributed computing paradigm, driven by economies of scale, in which a pool of abstracted, virtualized, dynamically-scalable and managed Computing power, Storage capabilities, Software platforms and Services are delivered on demand to external customers over the Internet (Armbrust et al. 2009). The main characteristics of Cloud Computing as a specialized distributed computing paradigm are the following (Brunette and Mogull 2009):
Scalability and elasticity. Cloud resources can be dynamically ("on-demand") delivered in real-time on a fine-grained and self-service basis. Users are able to re-provision with technological infrastructure resources;
Economies of scale. It is claimed to be free of charge or low cost even for hardware upgrades. Capital expenditure is converted to operational expenditure in a public cloud delivery model. The cost of licensing different software packages is moved to the data center level and there is no need to upgrade the local system when new service packs or patches are released. Also the infrastructure is centralized in low cost locations (such as real estate, electricity, etc.);
Abstract entity. It can encapsulate and deliver different levels of services to customers outside the Cloud. The services can be dynamically configured (via virtualization or other approaches) and delivered on demand.
Accessibility to software enables machines to interact with cloud software in the same way the user interface facilitates interaction between humans and computers. Users can reach the same result by using any Internet connected device having minimum software requirements. Cloud computing systems typically use REST-based API (Application Programming Interface).
Device and location independence enables users to access systems using a web browser regardless of their location or what device they are using (e.g., PC, mobile phone). Devices with minimal hardware requirements could be successfully used as cloud clients. As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, there is no need to download or install a specific software, only the Internet connection is required, in order to become part of the Cloud;
High reliability is achieved because multiple redundant sites are used. In case of client computer crashes, almost no data are lost due to centralized storage into the multiple cloud resources. Thus well-designed cloud computing are suitable for business continuity and disaster recovery.

33

International Journal of Computer Science Research and Application, 2(1):31-41


Improved security is achieved due to centralization of data, increased security-focused resources, etc. In comparison with the traditional systems, cloud security is better, because providers are able to devote more resources to solving security issues that many customers cannot afford. However, the complexity of security is greatly increased when data is distributed over a wider area or greater number of devices and in multi-tenant systems that are being shared by unrelated users. Private cloud installations are in part motivated by users' desire to retain control over the infrastructure and to avoid losing control of certain sensitive data or lack of security for stored kernels.
Improved efficiency and utilization for under-used systems (only 10–20% often utilized). Increased peakload capacity is achieved with no need to engineer for highest possible load-levels on the client side;
Constant performance monitoring. Most of the consistent and loosely coupled architectures are implemented using web services as the system interface.
Maintenance of cloud computing applications is easier, because they do not need to be installed on each user's computer. They are easier to support and to improve, as the changes reach the clients instantly. On the other side, few Cloud Computing disadvantages could be indentified:
overall performances may be affected by the Internet connection transfer rate;
data center subscription fee may be more expensive than the private hardware costs, on a long term basis;
data security require a high level QoS (Quality of Service) management and the need for backups is critical. In Cloud Computing architectural stack Provider Side Management complexity is increasing to maximum while User Side Management complexity is decreasing to zero for Software as a Service (SaaS) layer.

Figure 1: Traditional IT Architectural Stack vs. Cloud Computing 3-layered Architectural Stack. Cloud computing systems are implemented and structured over 5 (3+2) layers. They have 3 service layers (Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS)) and 2 complementary functional layers (Client Layer and Server/Fabric Layer). Client Layer is placed on top of the stack-like structure, while Server/Fabric Layer is placed at the bottom of the same structure, as the basic or fundamental physical layer (figure 2): 1) Client Layer may be any computer hardware device (e.g. regular PCs, notebooks, mobile phones, PDAs or any other similar equipments) and/or computer software application (operating systems, web browsers) that relies on cloud computing for application delivery and that is in essence useless without it.

34

International Journal of Computer Science Research and Application, 2(1):31-41

2) Software as a Service (SaaS). Cloud application layer deliver software as a service over the Internet, eliminating the need to install and run the application on the customer's own computers and simplifying maintenance and support. Software as a Service (SaaS) delivers special-purpose software that is remotely accessible by consumers through the Internet with a usage-based pricing model. Salesforce is an industry leader in providing online CRM (Customer Relationship Management) Services. Live Mesh from Microsoft allows files and folders to be shared and synchronized across multiple devices. Partial taxonomy: Google App, Microsoft Dynamics CRM online, Microsoft Live@edu, Business Producivity Online Suite, Exchange Hosted Services, Microsoft Office Web Apps, CampusEAI, EducationERP.net, Campus Management, Jaspersoft, Coupa's e-Procuiement. 3) Platform as a Service (PaaS). Cloud platform services deliver a computing platform and/or solution stack as a service, often consuming cloud infrastructure and sustaining cloud applications. It facilitates deployment of applications without the cost and complexity of buying and managing the underlying hardware and software layers. The Platform Layer adds on a collection of specialized tools, middleware and services on top of the unified resources to provide a development and/or deployment platform. For instance, a Web hosting environment, a scheduling service, etc. Platform as a Service (PaaS) offers a highlevel integrated environment to build, test, and deploy custom applications. Generally, developers will need to accept some restrictions on the type of software they can write in exchange for built-in application scalability. An example is Google’s App Engine , which enables users to build Web applications on the same scalable systems that power Google applications. Partial taxonomy: Google App Engine, Microsoft Azure Services, Amazon SimpleDB, Microsoft SDS, Oracle Higher Education Constituent Hub, Amazon SQS, Dynamsoft, Force.com, Microsoft Dynamics CRM online. 4) Infrastructure as a Service (IaaS). Cloud infrastructure services deliver computer infrastructure – typically a platform virtualization environment – as a service, along with raw (block) storage and networking. Clients can access these resources as a fully outsourced service. The amount of resources consumed (and therefore the cost) will typically reflect the level of utility computing activity. Infrastructure as a Service (IaaS) provisions hardware, software, and equipments to deliver software application environments with a resource usage-based pricing model. Infrastructure can scale up and down dynamically based on application resource needs. Typical examples are Amazon EC2 (Elastic Cloud Computing) Service and S3 (Simple Storage Service) where compute and storage infrastructures are open to public access with a utility pricing model. Eucalyptus is an open source Cloud implementation that provides a compatible interface to Amazon’s EC2, and allows people to set up a Cloud infrastructure at premise and experiment prior to buying commercial services. Partial taxonomy: EducationERP.net, Amazon S3-EBS- EC2, Eucalyptus, Microsoft, Oracle Coherence, Rackspace, RightScale, 3Tera App Logic, EnStratus, Flexiscale, GoGrid, CloudStatus, CampusEAI.

Client Layer Collaboration E-Learning Processes

Administration Research Applications

Server / Fabric Layer Figure 2:

Cloud Computing structuring layers

35

International Journal of Computer Science Research and Application, 2(1):31-41

5) Server or Fabric Layer contains the raw hardware resources, such as computing resources, storage resources, and network resources. These computer hardware and/or computer software products are specifically designed for the delivery of cloud services, including multi-core processors, cloud-specific operating systems and combined offerings. The complete Cloud Computing taxonomy can be found in a technical report from Cloud Security Alliance Organisation (Brunette and Mogull 2009).

3. Cloud Computing for E-learning The architectural pattern of Cloud Computing-based E-learning systems follows the layered structure of services (Saas, PaaS, and IaaS) and abstract/virtualized resources offered by Cloud Computing (figure 2). Studying the related work in this domain, one may found several interesting achievements and implementations. A brief analysis of these systems is presented here. Several modern Cloud Computing-based e-Learning applications that can use IaaS for dynamic assignable storage and compute resources were proposed by (Dong et al. 2009a). They describe a general and simple architecture with monitoring, policy and provision modules. BlueSky cloud framework (Dong et al. 2009b), developed by Xi’an Jiaotong University (China), enables physical machines to be virtualized and allocated on-demand for e-Learning systems. The BlueSky framework is focused on delivering IaaS and has some architectural layers dealing with physical resources, provisioning, monitoring and user interface but no security layer for user access policies. Virtual Computing Laboratory (VCL) (Vouk et al. 2008), developed by North Carolina State University (USA), enables students to reserve and access virtual machines (VMs) with a basic image or specific applications environments, such as Matlab and Autodesk. VCL does not offer collaboration features, but offers (IaaS and PaaS) platforms which could be used to host collaboration systems (SaaS) on top of it. Snow Leopard Cloud (Cayirci et al. 2009) provides PaaS for North Atlantic Treaty Organization (NATO) to run its various military exercises and mission events. In addition, Snow Leopard is used to run web 2.0 applications, such as video teleconferencing, voice over IP, and remote management, over handheld devices and terminals. As Snow Leopard Cloud is targeted towards military usage, it has a multi-level security and the network infrastructure is encrypted.

Figure 3:

Cloud Computing architectural levels for E-learning

36

International Journal of Computer Science Research and Application, 2(1):31-41

Figure 4:

“Campus Hybrid Cloud”-IBM Cloud Computing Solutions for E-learning

The Google App Engine provides a Java web framework. It is based on the servlet container Jetty and BigTable for data storage. Applications written for Google App Engine are scaled automatically by Google. Finally, IBM proposes its own hybrid cloud computing solution for E-learning in higher education domain as shown in figure 4.

4. Private Cloud Computing Architecture for E-learning A basic architecture for Private Cloud Computing-based E-learning systems follows the same layered structure of services (Saas, PaaS, and IaaS) and abstract/virtualized resources (figure 5).

Figure 5:

The E-learning system basic architecture using a Private Cloud Computing design

37

International Journal of Computer Science Research and Application, 2(1):31-41

In order to effectively respond to E-learning demands, the emerging Private Cloud should feature important attributes like reliability of services, scalability, elasticity and metered-by-use self-service. The main technologies used to build the Private Cloud are shown in figure 6 and table 1.

Figure 6:

The main Microsoft technologies used in Private Cloud-based E-learning system

Table 1: Microsoft Virtualization Technologies used in Private Cloud Computing Architecture Technological Scope Basic Private Cloud Advanced Private Cloud Virtualization Virtualization Server Hyper-V 2008 R2 Virtualization Server Hyper-V 2008 R2 Virtualization SCVMM (System Center Virtual SCVMM (System Center Virtual Management Machine Manager) 2008 R2 Machine Manager) 2008 R2 SSP (Self Service Portal) 2.0 DDTK (Dynamic Datacenter ToolKit) AdvancedManagement Configuration Manager and Orchestration Operations Manager Service Manager Data Protection Manager Opalis

Figure 7:

The Advanced Private Cloud architecture for E-learning systems

38

International Journal of Computer Science Research and Application, 2(1):31-41

The deployment model of private cloud computing can be used to design complex and virtual e-universities starting from an existing infrastructure. The proposed private cloud architecture is implemented on top of the heterogeneous hardware already present within university campus (figure 8). It consists of three computer collections/clusters (Education/Instruction Domain, Research Laboratory and Administrative Server Cluster), using separate IP subdomains within different locations of education institution. The Education/Instruction Domain computers may use a Linux operating system (e.g. Ubuntu) and may have KVM (Kernel-based Virtual Machine) installed, whereas the other clusters may have Debian OS and Xen configured. The computers from Education/Instruction Domain and Administrative Server Cluster are used by students and staff for teaching and administrative purposes while, the Research Laboratory servers are used for research and development purposes. All the computer collections/clusters are managed by a Cloud Middleware Management System (CMMS), as shown in figure 9. The CMMS is divided into several layers for extensibility and maintainability, while Monitoring, Management and Security components are incorporated across all layers to ensure high reliability and secured services, as described in the following paragraphs:
User Interface Layer provides various access points to users and/or administrators of the cloud system CMMS;
Business Layer regulates resource supply and demand to comply to economically use and Service-Level Agreements (SLA). This layer enables users to reserve VMs (Virtual Machines) in advance and manage their personal VMs (Virtual Machines);
System Layer monitors daily operations of the CMMS, such as submitting jobs, managing user accounts and monitoring Quality of Service (QoS);
Resource Interface Layer deals with the physical hardware. It provides interfaces and plug-ins to various virtualization, database and distributed systems as well as other technologies, such as Xen, Amazon EC2, Amazon S3, and Nagios; Monitoring & Management Component ensures the reliability of each layer in the cloud. This component allows system administrator to monitor and to initiate activities of each layer, in case of failures, conflicts with SLA (Service-Level Agreements) objectives, under- or over-utilized resources.
Security and Identity Management Component ensures the privacy, recovery, integrity and security of user data and transactions, on all system layers. It is based on an open source software package for cloud single sign-on across or within organizational boundaries (Shibboleth System) is a standards based. It allows users to make informed authorization decisions for individual access of protected online resources in a privacypreserving manner. Education / Instruction Domain Intel Xeon Processors E7 Platforms

Cloud Middleware Management System

Intel Itanium Processors 9000 Platforms

Research Laboratory Servers

Intel Xeon Processors E5 Platforms

Administrative Server Cluster

Figure 8:

Cloud Computing architecture for E-learning

39

International Journal of Computer Science Research and Application, 2(1):31-41

Monitoring & Management Component

Security & Identity Management Component

Cloud Middleware Management System

Figure 9:

Cloud Middleware Management System for E-learning

5. Managing E-learning Processes within Cloud Computing Architecture Cloud computing provides virtual e-universities with a fundamentally different model of operation among Elearning processes. This new model takes advantage of the maturity of web applications and networks and the rising interoperability of computing systems to provide IT services. Cloud providers specialize in particular applications and services, and this expertise allows them to efficiently manage upgrades and maintenance, backups, disaster recovery, and failover functions. As a result, e-university consumers of cloud services may see increased reliability, even as costs decline due to economies of scale and other production factors. With cloud computing, e-universities can monitor current needs and make on-the-fly adjustments to increase or decrease capacity, accommodating spikes in demand without paying for unused capacity during slower times. Cloud computing scalability is another key benefit to higher education, particularly for research projects that require vast amounts of storage or processing capacity for a limited time. Aside from the potential to lower costs, e-universities gain the flexibility of being able to respond quickly to requests for new services by purchasing them from the cloud. Cloud computing allows e-universities and Elearning services providers to make IT costs transparent and thus match consumption of E-learning services to actual demand. Cloud computing encourages E-learning organizations and providers to increase standardization of protocols and processes so that the many pieces of the cloud computing model can interoperate properly and efficiently. An advanced Learning Management System (LMS) deployed on a Cloud Computing Architecture has a significant role and complexity in e-learning environment and must comply with the following requirements:
Compatibility and ability to collaborate with other LMS;
Performance and extendibility of the whole environment;
Reusability and compatibility of e-learning content with existing standards: SCORM (Sharable Content Object Reference Model), IEEE Learning Object Metadata (LOM), IMS GLC (IMS Global Learning Consortium) Learning Resource Metadata Specification, ARIADNE (Alliance of Remote Instructional Authoring and Distribution Networks for Europe) Metadata Specification, AICC (Aviation Industry Computer-Based Training Committee) Metadata Specification;
Creation of Hypermedia Reusable Learning Object (HRLO) from different input learning content format (PDF, MPEG, MS Office, JavaScript, PHP, SCORM, IMS Content Package, etc.);
Support for the common content creation tools (Dreamweaver, Adobe Flash, PowerPoint, Word);
Content management ability such as electronic filling and file management;
Fast content creation, distribution, integration and authorizing tools;

40

International Journal of Computer Science Research and Application, 2(1):31-41












Modular structure including tools for e-learning content installation, development and management; XML support to work with different systems and easily integrate metadata for e-learning ontology creation; Database support with advanced search and header hiding ability Video Conferencing support and chat tool Survey campaign support Management of studding groups and debate forums Online assessment module Calendar, backup support and whiteboard Multi-Language support Some of the most widely used open source Learning Management Systems (LMS) are briefly described in Table 2: Table 2: Advanced Open Source Learning Management Systems Deployed on Private Cloud Architecture LMS Compatibility System Requirements Apache, MySQL, and PHP Moodle Linux, UNIX, Windows, Mac OS X, http://www.moodle.org/ FreeBSD, and any other system that supports PHP Apache, MySQL, and PHP

ATutor http://www.atutor.ca/

Complies with W3C WCAG 1.0 and W3C XHTML 1.0; supports content developed in IMS or SCORM.

Dokeos http://www.dokeos.com/

Supports SCORM import and LDAP. Data can Apache, MySQL, and PHP be imported using CSV or XML files.

OLAT http://www.olat.org/ Microsoft Windows, Mac OS X, Linux, Solaris, and UNIX. Conforms to SCORM, IMS QTI, and IMS Content Packaging.

Java 1.5, Tomcat 5, MySQL 4.1, Apache 2.0 and OpenFire3.3

Bodington http://www.bodington.org

Shibboleth, Linux, Microsoft, Mac OS X, or UNIX

Apache, MySQL, and PHP

Claroline http://www.claroline.net/

Microsoft, Linux/GNU, Mac OS X; complies SQL Server, IIS, .NET, Java 1.5, Apache, MySQL, and PHP with SCORM and IMS/QTI.

.LRN http://www.dotlrn.com/

LORS Central, Curriculum, LORS Management, .LRN Ecommerce, Project Manager, Page Editor, Staff List, Syllabus, Expense Tracking

Sakai Complements commercial software like http://www.sakaiproject.org/ WebCT, Blackboard, ANGEL Learning, and Desire2Learn.

Apache, MySQL, and PHP

Apache, MySQL, PHP, and Java

5. Conclusions The idea behind Cloud Computing is to deliver Infrastructure as a Service (IaaS), 3), Platform as a Service (PaaS), and Software as a Service (SaaS) over the Internet on a scalable level, using an easy pay-per-use business model. The Cloud Computing technologies can be exploited to build the next generation of platformindependent tools and scalable data storage for E-learning systems. This set of technologies can distribute applications across a wider set of devices and can make great reduction in the overall cost of computing. Even a virtual and personal learning environment can be implemented, using a combination of a wide range of services available in the cloud. The proposed Private Cloud-based E-learning system enables educational content design and monitoring, and has a service oriented architecture that simplifies the management and increases the effective utilization of the cloud resources.

41

International Journal of Computer Science Research and Application, 2(1):31-41

Acknowledgment This paper was accomplished as part of the research project no. 551/2009 granted by Romanian CNCSIS.

References Cayirci, E., Rong, C., Huiskamp, W., Verkoelen, C. (2009): Snow Leopard Cloud: A Multi-national Education Training and Experimentation Cloud and Its Security Challenges. In: Proceedings of the 1st International Conference on Cloud Computing (CloudCom 2009), Beijing, China Dong, B., Zheng, Q., Yang, J., Li, H., Qiao,M. (2009a): An E-learning Ecosystem Based on Cloud Computing Infrastructure. In: Advanced Learning Technologies, 2009. ICALT 2009. Ninth IEEE International Conference on. 125 –127 Dong, B., Zheng, Q., Qiao, M., Shu, J., Yang, J. (2009b): BlueSky Cloud Framework: An E-Learning Framework Embracing Cloud Computing. In: Proceedings of the 1st International Conference on Cloud Computing (CloudCom 2009), Beijing, China (165–171). Foster, I., Zhao, Y., Raicu, I., Lu, S. (2008): Cloud Computing and Grid Computing 360-Degree Compared. In: Proceedings of the Grid Computing EnvironmentsWorkshop (GCE’08), Austin, Texas, USA 116-120 Vouk, M., Averritt, S., Bugaev, M., Kurth, A., Peeler, A., Schaffer, H., Sills, E., Stein, S., Thompson, J. (2008): “Powered by VCL” – Using Virtual Computing Laboratory (VCL) Technology to Power Cloud Computing. In: Proceedings of the 2nd International Conference on the Virtual Computing Initiative (ICVCI’08). Technical Reports: Armbrust, M., Fox, A., Griffith, R., Joseph, A.D., Katz, R., Konwinski, A., Lee, G., Patterson, D., Rabkin, A., Stoica, I., Zaharia, M. (2009).: Above the Clouds: A Berkeley View of Cloud Computing. Technical Report UCB/EECS-2009-28, Univ. of California at Berkeley Brunette, G. & Mogull, R. (2009). “Security Guidance for Critical Areas of Focus on Cloud Computing,” Cloud Security Alliance. http://www.cloudsecurityalliance.org/guidance/csaguide.v2.1.pdf Internet Sources: Fully Automated Installation (FAI). http://www.informatik.unikoeln.de/fai/ GoogleAppEngine: Google’s PaaS infrastructure.http://code.google.com/appengine/ JMeter: Apache JMeter. http://jakarta.apache.org/jmeter/ Libvirt: virtualization API. http://libvirt.org/ LDAP: Lightweight Directory Access Protocol http://tools.ietf.org/html/rfc4510 Nagios: Nagios: IT-infrastruktur monitoring tool. http://www.nagios.org/ OLAT: Online Learning And Training. http://www.olat.org/ Qumranet: KVM: White Paper. http://www.linux-kvm.org/ Shibboleth:: A Single-Sign-On Solution. http://shibboleth.internet2.edu/ TimeEdit. http://www.timeedit.com/

A Brief Author Biography Eugen ZAHARESCU, (Ph.D. in Electronics and Telecommunications), graduated the Faculty of Electronics and Telecommunications (Applied Electronics), Polytechnic University of Bucharest in 1981. Here, he prepared and presented in 2003 his Ph.D. thesis: “Extending Mathematical Morphology for Colour Images and for Logarithmic Representation of Images”. Also, he graduated the Mathematics & Informatics Faculty–Bucharest University and he received “Diplome Internationale de Management”-Universite des Sciences Sociales-Toulouse, France (1995). Now he is Associate Professor at “OVIDIUS” University of Constanta, Romania. During the past 20 years he delivered higher education courses in highlevel programming languages, operating systems and networking, web technologies and data base. Since 2008 he joined every year the International Conference on Virtual Learning community and presented here 4 papers concerning Elearning technologies.

Copyright for articles published in this journal is retained by the authors, with first publication rights granted to the journal. By the appearance in this open access journal, articles are free to use with the required attribution. Users must contact the corresponding authors for any potential use of the article or its content that affects the authors’ copyright.