Review Questions and Answers on Cloud Overview 1. was known to be a solution for the following problems: a. of Enterprise applications b. Disaster – failure due to unplanned demand . Increasing Capital investment on IT Infrastructure Explain the nature of the problem and how cloud computing is able to address them. See answer for a) http://www.latisys.com/blog-post/enterprise-cloud-services-solve-it- scalability-problems See answer for b) http://www.iland.com/solutions/disaster-recovery/ http://searchdisasterrecovery.techtarget.com/feature/Disaster-recovery-in-the-cloud- explained http://www.onlinetech.com/404 See answer for c) http://www.opengroup.org/cloud/cloud/cloud_for_business/roi.htm 2. Briefly describe the ways that cloud computing are both similar and different to . In the mid 1990s, the term Grid was coined to describe technologies that would allow consumers to obtain computing power on demand. Ian Foster and others posited that by standardizing the protocols used to request computing power, we could spur the creation of a Computing Grid, analogous in form and utility to the electric power grid. Researchers subsequently developed these ideas in many exciting ways, producing for example large- scale federated systems (TeraGrid, Open Science Grid, caBIG, EGEE, Earth System Grid) that provide not just computing power, but also data and software, on demand. Standards organizations (e.g., OGF, OASIS) defined relevant standards. More prosaically, the term was also co-opted by industry as a marketing term for clusters. But no viable commercial Grid Computing providers emerged, at least not until recently.

So is “Cloud Computing” just a new name for Grid? In information technology, where technology scales by an order of magnitude, and in the reinvents itself, every five years, there is no straightforward answer to such questions.

Yes: the vision is the same—to reduce the cost of computing, increase reliability, and increase flexibility by transforming from something that we buy and operate ourselves to something that is operated by a third party. But no: things are different now than they were 10 years ago. We have a new need to analyze massive data, thus motivating greatly increased demand for computing. Having realized the benefits of moving from mainframes to commodity clusters, we find that those clusters are quite expensive to operate. We have low-cost . And, above all, we have multiple billions of dollars being spent by the likes of Amazon, Google, and to create real commercial large-scale systems containing hundreds of thousands of computers. The prospect of needing only a credit card to get on-demand access to 100,000+ computers in tens of data centers distributed throughout the world—resources that be applied to problems with massive, potentially distributed data, is exciting! So we are operating at a different scale, and operating at these new, more massive scales can demand fundamentally different approaches to tackling problems. It also enables—indeed is often only applicable to—entirely new problems.

Nevertheless, yes: the problems are mostly the same in Clouds and Grids. There is a common need to be able to manage large facilities; to define methods by which consumers discover, request, and use resources provided by the central facilities; and to implement the often highly parallel computations that execute on those resources.

3. What are the factors contributing to the surge and interest in cloud computing? There are three main factors contributing to the surge and interests in Cloud Computing: 1) rapid decrease in hardware cost and increase in computing power and storage capacity, and the advent of multi-core architecture and modern consisting of hundreds of thousands of cores; 2) the exponentially growing data size in scientific instrumentation/simulation and Internet publishing and archiving; and 3) the wide-spread adoption of Services Computing and Web 2.0 applications.

4. Give a summary of comparison between Grid Computing and Cloud Computing with respects to the architecture, security model, business model, programming model, virtualization, data model, compute model to provenance and applications.

5. Briefly define the following basic techniques and technologies that represent recent related advances in architecture, parallel processing, , Internet technology, and information services: a. High-performance computing (HPC) system b. High-throughput computing (HTC) system c. Peer-to-peer (P2P) network d. Computer cluster versus computational grid e. Service-oriented architecture (SOA) f. Pervasive computing versus Internet computing g. versus virtual infrastructure h. Public cloud versus private cloud i. Radio-frequency identifier (RFID) j. Global positioning system (GPS) k. Sensor network l. Internet of Things (IoT) m. Cyber-physical system (CPS)

6. An increasing number of organizations in industry and business sectors adopt cloud systems. Answer the following questions regarding cloud computing: a. List and describe the main characteristics of cloud computing systems. b. Discuss key enabling technologies in cloud computing systems. c. Discuss different ways for cloud service providers to maximize their revenues.

7. Compare the similarities and differences between traditional computing clusters/grids and the computing clouds launched in recent years. Consider all technical and economic aspects as listed below. Answer the following questions against real example systems or platforms built in recent years. Also discuss the possible convergence of the two computing paradigms in the future. a. Hardware, software, and networking support b. Resource allocation and provisioning methods c. Infrastructure management and protection d. Support of services e. Operational and cost models applied

(a) Hardware, software and networking support As cloud platforms are built on top of datacenters, the hardware resources of cluster/grid could be part of a larger computing cloud. Cloud typically needs some kind of web service or software like a Web browser. Also, components of a cloud may be more sparsely distributed, which needs a wider network support. (b) Resource allocation and provisioning methods Cloud resources are dynamically provisioned by datacenters upon user demand while clusters are not. Additionally, cloud system provides computing power, storage space and flexible platforms for upgraded web-scale application services. (c) Infrastructure management and protection Cloud computing relies heavily on the virtualization of all sorts of resources, and it needs stronger protection than cluster/grid. (d) Supporting of utility computing services Cloud computing inherently supports utility computing services, just like electricity, while cluster/grid are usually deployed by individual enterprises and do not provide to public as utility. (e) Operational and cost models applied Cloud is more cost-effective than cluster/grid. Besides the advantages brought by virtualization, the customers of cloud do not have to buy infrastructure before using it. Also, QoS and SLA add extra requirement on the operational and cost models. In the future, the two computing paradigms can be converged. For example, there could be no so-called cluster. Everything is based on a comprehensive cloud. In this comprehensive cloud, a customer could request compute, storage and network resources as much as a traditional cluster. Thus, clusters are included in the cloud.

7.1 Compare the similarities and differences between traditional computing clusters/grids and the computing clouds launched in recent years.

8 Discuss the major advantages and disadvantages in the following areas: a. Why are virtual machines and virtual clusters suggested in cloud computing systems? b. What breakthroughs are required to build virtualized cloud systems cost-effectively? c. What are the impacts of cloud platforms on the future of the HPC and HTC industry?

9 Characterize the following three cloud computing models: a. What is an IaaS (Infrastructure-as-a-Service) cloud? Give one example system. b. What is a PaaS (Platform-as-a-Service) cloud? Give one example system. c. What is a SaaS (Software-as-a-Service) cloud? Give one example system.

10 Briefly explain each of the following cloud computing services. Identify two cloud providers by company name in each service category. a. Application cloud services b. Platform cloud services c. Compute and storage services d. Collocation cloud services e. Network cloud services