Cloud Computing

Unit1 : Introduction to Cloud Computing -Question Bank How does cloud computing aim to provide computing resources in a fully virtualized manner? What is utility computing and how does it relate to cloud computing? Define cloud computing and its unique characteristics according to different sources. What are the key characteristics of cloud computing according to the University of California Berkeley report? How does the National Institute of Standards and Technology (NIST) characterise cloud computing? How do Armbrust et al. define cloud computing? What are some common characteristics of a cloud computing environment? With diagram explains the roots of cloud computing.  How has cloud computing realised the long-held dream of delivering computing as a utility? How did the shift from mainframes to utility computing influence the development of cloud computing? What is the role of Web services, service-oriented architectures, and Web 2.0 in the context of cloud computing? How ha...

 Q1: What is the concept of virtualization in the context of electricity and computing? A1: Virtualization refers to the abstraction of underlying infrastructure or resources, allowing users to access and utilize them without having to understand the details of their internal workings. In the context of electricity, virtualization allows us to plug in electric appliances without having to worry about power generation or distribution. Similarly, in computing, virtualization enables the creation of virtual machines or environments that hide the complexities of the underlying hardware and infrastructure. Q2: How have technologies like cluster, grid, and cloud computing contributed to virtualization and utility computing? A2: Technologies such as cluster, grid, and cloud computing have aimed to provide access to large amounts of computing power in a fully virtualized manner. They aggregate resources from distributed components, such as processing, storage, data, and software, and offer...

 Typically migration initiatives into the cloud are implemented in phases or in stages. A structured and process-oriented approach to migration into a cloud has several advantages of capturing within itself the best practices of many migration projects.  After due study and practice, we share the Seven-Step Model of Migration into the Cloud as part of our efforts in understanding and leveraging the cloud computing service offerings in the enterprise context. In a succinct way,  The Following Figure captures the essence of the steps in the model of migration into the cloud,  while the above Figure captures the iterative process of the seven-step migration into the cloud.  Cloud migration assessments comprise assessments to understand the issues involved in the specific case of migration at the application level or the code, the design, the architecture, or usage levels. In addition, migration assessments are done for the tools being used, the test cases as well a...

Given that cloud computing is a “techno-business disruptive model” and is on the top of the top 10 strategic technologies to watch for 2010 according to Gartner,7 migrating into the cloud is poised to become a large-scale effort in leveraging the cloud in several enterprises.  “Cloudonomics” deals with the economic rationale for leveraging the cloud and is central to the success of cloud-based enterprise usage.  At what IT costs would one want to migrate into the cloud?  While all capital expenses are eliminated and only operational expenses incurred by leveraging the cloud, does this satisfy all strategic parameters for enterprise IT?  Does the total cost of ownership (TCO) become significantly less as compared to that incurred when running one’s own private data center?  Decision-makers, IT managers, and software architects are faced with several dilemmas when planning for new Enterprise IT initiatives. 1.10.1. Why Migrate? There are economic and business reas...

Cloud computing has been an attractive proposition both for the CFO and the CTO of an enterprise primarily due its ease of usage. This has been achieved by large data center service vendors or now better known as cloud service vendors again primarily due to their scale of operations. Google, Amazon, Microsoft, and a few others have been the key players apart from open source Hadoop built around the Apache ecosystem As shown in Figure  the cloud service offerings from these vendors can broadly be classified into three major streams: the Infrastructure as a Service (IaaS), the Platform as a Service (PaaS), and the Software as a Service (SaaS). While IT managers and system administrators preferred IaaS as offered by Amazon for many of their virtualized IT needs, the programmers preferred PaaS offerings like Google AppEngine (Java/Python programming) or Microsoft Azure (.Net programming).  Users of large-scale enterprise software invariably found that if they had been using t...

  As shown in Figure, the promise of the cloud both on the business front (the attractive cloudonomics) and the technology front widely aided the CxOs to spawn out several non-mission critical IT needs from the ambit of their captive traditional data centers to the appropriate cloud service.  Invariably, these IT needs had some common features: They were typically Web-oriented; they represented seasonal IT demands; they were amenable to parallel batch processing; they were non-mission critical and therefore did not have high security demands. They included scientific applications too. Several small and medium business enterprises, however, leveraged the cloud much beyond the cautious user. Many startups opened their IT departments exclusively using cloud services—very successfully and with high ROI.  Having observed these successes, several large enterprises have started successfully running pilots for leveraging the cloud. Many large enterprises run SAP to manage their o...

The promise of cloud computing has raised the IT expectations of small and medium enterprises beyond measure. Large companies are deeply debating it.  Cloud computing is a disruptive model of IT whose innovation is part technology and part business model—in short a “disruptive techno-commercial model” of IT.  This tutorial chapter focuses on the key issues and associated dilemmas faced by decision makers, architects, and systems managers in trying to understand and leverage cloud computing for their IT needs. Questions asked and discussed in this chapter include:  when and how to migrate one’s application into a cloud;  what part or component of the IT application to migrate into a cloud and what not to migrate into a cloud; what kind of customers really benefit from migrating their IT into the cloud; and so on.  We describe the key factors underlying each of the above questions and share a Seven-Step Model of Migration into the Cloud.

Despite the initial success and popularity of the cloud computing paradigm and the extensive availability of providers and tools, a significant number of challenges and risks are inherent to this new model of computing. Providers, developers, and end users must consider these challenges and risks to take good advantage of cloud computing.  Issues to be faced include user privacy, data security, data lock-in, availability of service, disaster recovery, performance, scalability, energy-efficiency, and programmability. 1.8.1 Security, Privacy, and Trust The information security as a main issue: “current cloud offerings are essentially public ... exposing the system to more attacks.” For this reason there are potentially additional challenges to make cloud computing environments as secure as in-house IT systems. At the same time, existing, well understood technologies can be leveraged, such as data encryption, VLANs, and firewalls. Security and privacy affect the entire cloud computing...