CU-MCA-SEM-II-Cloud Computing-Second Draft

MASTER OF COMPUTER APPLICATION SEMESTER-II CLOUD COMPUTING

First Published in 2021 All rights reserved. No Part of this book may be reproduced or transmitted, in any form or by any means, without permission in writing from Chandigarh University. Any person who does any unauthorized act in relation to this book may be liable to criminal prosecution and civil claims for damages. This book is meant for educational and learning purpose. The authors of the book has/have taken all reasonable care to ensure that the contents of the book do not violate any existing copyright or other intellectual property rights of any person in any manner whatsoever. In the event the Authors has/ have been unable to track any source and if any copyright has been inadvertently infringed, please notify the publisher in writing for corrective action. . 2 CU IDOL SELF LEARNING MATERIAL (SLM)

CONTENT Unit 1 – Cloud Computing Fundamentals........................................................................ 4 Unit 2 - Layers In Cloud Computing ............................................................................. 21 Unit 3 - Types Of Cloud Computing ............................................................................. 42 Unit 4 – Cloud Computing ............................................................................................ 65 Unit 5 – Cloud Computing Architecture ........................................................................ 75 Unit 6 - Cloud Service Management.............................................................................. 92 Unit 7 - Scalability ...................................................................................................... 103 Unit 8 - Microsoft Azure ............................................................................................. 114 Unit 9 - Resource Management ................................................................................... 142 Unit 10 - Virtualization ............................................................................................... 153 Unit 11 - Data Management ........................................................................................ 179 Unit 12 - Traffic Manager ........................................................................................... 194 Unit 13 - Cloud Storage .............................................................................................. 205 Unit 14 - Types Of Storage ......................................................................................... 215 Unit 15 - Security........................................................................................................ 226 3 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT 1 – CLOUD COMPUTING FUNDAMENTALS STRUCTURE 1.0 Learning Objectives 1.1 Introduction 1.2 Computing paradigms 1.3 Definition 1.4 NIST Model 1.5 Characteristics of Cloud Computing Model 1.6 Benefits of Cloud Computing 1.7 Cloud Computing Vs Cloud Services 1.8 Summary 1.9 Keywords 1.10Learning activity 1.11Unit end-Questions 1.12References 1.0LEARNING OBJECTIVES After studying this unit students will be able to:  Describe the basics of cloud computing  Analyse Sensors and Actuators and their differences  Describe the definition of IoT and its characteristics  Outline Functional block of IoT and communication models  Examine API 1.1INTRODUCTION Microsoft Azure is the company's cloud computing platform, which lets us access a wide range of services without having to buy or provide our own hardware. Azure offers quick solution creation and delivers the resources needed to complete activities that would be impossible to complete from an on environment. Azure's computing, storage, networking, and application services let us focus on developing great solutions instead of worrying about how the actual infrastructure is put up. 4 CU IDOL SELF LEARNING MATERIAL (SLM)

This chapter teaches you the basics of Azure so that anyone can get started designing solutions straight away. It focuses on the Azure platform capabilities when we are most likely to have to know instead of every functionality and service accessible. This chapter also includes various walkthroughs for creating Vm and virtual networks, websites, and storage accounts, among other things. Real-world advice is frequently offered to help us get through our Azure experience. The book examines standard tools for designing and implementing Azure-based solutions in addition to covering essential Azure capabilities. The book concludes by describing a few basic business scenarios in which Azure might deliver appealing and useful solutions. 1.2CLOUD COMPUTING PARADIGM The use of someone else's server to host, process, or save data is referred to as cloud computing.Cloud computing is a sort of computing in which on-demand computer services are delivered through the online on a pay-as-you-go approach. It's a broadly dispersed, network-based storage system. There are four types of clouds: public, private, hybrid, and community, with Google Cloud, Amazon Web Services, Microsoft Azure, and IBM Cloud as examples of cloud providers.Cloud computing is an IT paradigm that offers universal access to the shared pools of customizable system control and greater functions that can be swiftly deployed with low management work, frequently through the Internet. Cloud computing, like a public utility, relies on resource sharing for achieve coherence and economy of scale. Cost reductions, scalability, and high availability are all advantages of cloud computing technology. 5 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.1Cloud Computing History of Cloud Computing Before we get into the other aspects of cloud computing, let's take a look at where cloud computing comes into history and if it is truly unique or just the latest trend. From dummy terminals/mainframes through PCs, network computing, grid, and cloud computing, Figure 1.2, based from Voas and Zhang (2009), depicts six periods of computing paradigms. Dummy terminals have been used in Phase 1 for link to powerful hosts that allow several computers to communicate with one another. You might work on a computer, but there are some significant contrasts between the two paradigms. A cloud, in contrast to a mainframe, which would be a physical system with fixed processing power, symbolises all conceivable Internet resources, implying limitless power and capacity. Meanwhile, unlike a basic terminal serving as just a user interface to something like a mainframe, a PC under the cloud computing paradigm has enough processing capacity to perform some local computation and caching. In brief, cloud computing has emerged as a key technological trend that has the potential to transform the IT industry and marketplace. can share resources by connecting to other computers via local networks (LAN). Local networks were joined to other local networks in Phase 4 to create a larger global network, 6 CU IDOL SELF LEARNING MATERIAL (SLM)

allowing users to access remote applications and resources via the Internet. The notion of an electronic grid was introduced in Phase 5 to allow the sharing of computer power and storage resources (distributed computing). People utilised PCs to gain transparent access to a grid of computers. Now, in Phase 6, one can use cloud computing to take use of all accessible Internet resources in an incredibly scalable and straightforward manner. Figure 1.2 six periods of computing paradigms Voas and Zhang (2009) A conceptual layer, such as a cloud upon on Internet, hides all accessible resources (hardware or software) as well as services but broadcasts a standard interface, as seen in Figure 1.1. Users may utilise the entire Internet as their power PC as long because they can access the internet. The mechanisms that enable and assist this scenario are referred to as cloud computing. When such six computing paradigms are compared, cloud computing appears to be a reversion to just the original mainframe computer paradigm. However, there are numerous significant distinctions between these two paradigms. A cloud, in contrast to a mainframe, which would be a physical system with fixed processing power, symbolises all conceivable Internet resources, implying limitless power and capacity. Meanwhile, unlike a basic terminal serving as just a user interface to a mainframe, a PC under the cloud computing paradigm has enough processing capacity to perform some local computation and caching. In brief, cloud computing has emerged as a key technological trend that has the potential to transform the IT industry and marketplace. 7 CU IDOL SELF LEARNING MATERIAL (SLM)

1.3CLOUD COMPUTING -DEFINITIONS When we plug an electric gadget into such an outlet, we don't give a damn about how electricity is created or delivered to that outlet. This is feasible because electricity is virtualized, which means it may be obtained from a wall socket while power producing stations and a vast distribution infrastructure are hidden behind it. When used to information technology, this notion entails providing useful capabilities but concealing how they operate. Computing must allow computers to be created from dispersed components such as processor, storage, data, but also software resources in order to be called fully virtualized. Cluster, grid, but now cloud computing technologies have all tried to provide completely virtualized access to massive quantities of computing power by combining resources and providing a single system perspective. Furthermore, supplying computers as a utility has been a major goal of these technologies. Utility computing is a business model for on-demand computing power supply in which customers pay providers based on consumption (“pay as you go”), similar to how we now get services through traditional public utilities like water, electricity, gas, as well as telephones. Cloud computing is a catch-all name for a set more sophisticated on-demand computing resources first supplied by commercial companies like Amazon, Google, and Microsoft. It refers to a computing infrastructure that is perceived as a \"cloud\" from which organisations and people may access apps on demand from anywhere in the globe.This model's basic idea is to provide computation, storage, and software \"as a service.\"Many people in the business and academic worlds have tried to describe what \"cloud computing\" is and what distinguishes it from other technologies. “Cloud is a parallel and distributed computing system consisting of a set of interconnected and virtualized computers which are dynamically provisioned as well as presented also as or even more integrated computing resources based on service-level agreements (SLAs) implemented through negotiation between the service provider and consumers,” according to Buyya et al. “Clouds are a huge pool of easily useable and reachable virtualized resources (including such hardware, development platforms, and/or services),” according to Vaquero et al. [3]. These resources may be dynamically adjusted to react to a changing demand (scaling), allowing for the most efficient use of resources. This pool of resources is often used in a pay-per-use approach, with the Infrastructure Provider providing assurances through tailored Service Level Agreements.” “Clouds are hardware-based services delivering compute, network, as well as storage capacity in which: Hardware management is substantially abstracted from the buyer, purchasers suffer infrastructure expenses through variable OPEX, as well as infrastructure capacity is very elastic,” according to a recent McKinsey & Co. research. 8 CU IDOL SELF LEARNING MATERIAL (SLM)

The essential characteristics of cloud computing, according to a paper from the University of California Berkeley, are: (1)“the appearance of endless computing resources; (2) the removal of such an up-front commitment for cloud users; and (3) the flexibility to pay for use... as needed...” Cloud computing is defined as “a pay-per-use model for enabling available, convenient, on- demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, services) which can be rapidly provisioned but also released with minimal management effort or service provider interaction,” according to the National Institute of Standards and Technology (NIST). Armbrust et al. [5] give a more general definition of cloud as “data centre software and hardware that deliver services.” Similarly, Sotomayor et al. point out that the term \"cloud\" is more commonly used to refer to IT infrastructure placed in a data centre run by such an Infrastructure as a Service provider. While there is a plethora of different definitions, there appear to be certain commonalities among the most famous ones given above that a cloud should possess: I pay-per-use (no long-term commitment, utility costs); (ii) elastic capacity and the appearance of boundless resources; (iii) self-service interface; (iv) abstracted or virtualized resources. Cloud computing companies often provide a wide range of software services in addition to basic compute and storage. APIs and development tools are also available, allowing developers to create scalable apps using their services. Customers will eventually be able to run their daily IT infrastructure “in the cloud.”The cloud computing space has been surrounded by a lot of hype since its inception, and it is widely seen as the most important shift in the IT sector since the Internet's inception. Trying to discuss what cloud computing means and which computer infrastructures may be called \"clouds\" in the middle of all this excitement causes a lot of uncertainty. With both the advent of cloud computing, the long-held ambition of offering computers as a utility has come true. Several technologies, however, have grown through time and have greatly contributed to the viability of cloud computing. In this vein, this introduction traces the origins of cloud computing by examining the major technical breakthroughs that aided in the emergence of this new industry. It also clarifies ideas and advancements by classifying and comparing the most important cloud computing R&D activities, including public clouds, management tools, and development frameworks. The most important practical cloud computing implementations are mentioned, with an emphasis on architectural characteristics and cutting-edge technological characteristics. 1.4NIST MODEL Cloud computing is a concept that allows for easy, on-demand access to a configurable pools of computing resources (e.g., servers, networks, applications, storage, and 9 CU IDOL SELF LEARNING MATERIAL (SLM)

services).Resources may be supplied and released with little effort on the part of the manager. Figure 1.3 depicts NIST's visual model of cloud computing definition. It provides infrastructure, platform, and software to clients as pay-as-you-go subscription-based services. The following are the benefits, or important aspects, of employing a cloud computing model: Figure 1.3- NIST's visual model of cloud computing On-demand self-service: A consumer can provision computing capabilities when needed without having to engage with each service provider separately. Broad network access: Capabilities may be accessed from anywhere on the network. It may be accessible via standard techniques that can be utilized by thin and thick client platforms that are heterogeneous.Multiple customers are served from either a pool of computer resources using a multi-tenant paradigm. The consumer has had no control over where the offered resources are physically located. Rapid elasticity: The elasticity for storage as well as memory devices is supported by cloud computing. It has the ability to grow and contract as needed in response to user demand. Customers can access metering infrastructure using cloud computing. Users can take advantage of cost optimization methods that allow them to just provide and pay for the resources they utilize. 10 CU IDOL SELF LEARNING MATERIAL (SLM)

Virtualization technology would be used in cloud computing to abstract a range of computer resources and provide them to consumers as abstracted services. Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), and Software-as-a-Service are the three types of cloud services (SaaS). Infrastructure-as-a-Service (IaaS) offers clients with scalable infrastructure, such as servers, connected devices, and storage discs, as demand-based services. The cloud may be accessed using a variety of user interfaces, including web service application programming interfaces (APIs), command-line interfaces (CLIs), and graphical user interfaces (GUIs), each of which provides a different level of abstraction. Consumers have control over the process systems, storage, and installed apps, but they are not expected to maintain or oversee cloud infrastructure. PaaS (Platform-as-a-Service) is a platform that allows users or customers to design and run their own apps or programs. Users may create and distribute Web apps without having to download or install any software since the PaaS service takes care of everything. It is in charge of completing users' tasks in real time. The developers are the most essential clients for this tier. Software-as-a-Service (SaaS) is in charge of delivering various types of programs as well as end-user interfaces. Web browsers provide access to this cloud computing function. The SaaS style of software deployment allows customers to execute their apps without having to install software on their own computers. Nevertheless, this service is restricted to users, i.e., consumers may only access the present set of services. A cloud can be classed either public cloud, private cloud, community cloud, or hybrid cloud depending on the deployment architecture. Private cloud: A private cloud is just a virtual environment within an organization that is confined to company users and is often located while behind corporate firewall. It's ideal for sensitive data and essential systems that need to be kept safe. It can be found on or outside the premises. Community cloud: A Community cloud is comparable to a private cloud in terms of functionality. It is made available to a set of firms with comparable criteria that require additional functionalities. It can be found on or outside the premises. Public cloud: A public cloud is just a virtual environment where any user may acquire computer resources, generally on a pay-per-use basis, using an easy-to-use online site. It is located on the cloud provider's premises. Hybrid cloud: A hybrid cloud that combines public and private cloud resources, with certain resources being used in the public cloud and others in the private cloud. 11 CU IDOL SELF LEARNING MATERIAL (SLM)

1.5CHARACTERISTICS OF CLOUD COMPUTING AS PER NIST The National Institute of Standards and Technology (NIST) is a US Department of Commerce department. The National Institute of Standards and Technology (NIST) is in charge of establishing scientific and technological standards. The National Institute of Standards and Technology's Computer Security Division has published a detailed Description as well as Characteristics of Cloud Computing. The five basic qualities of cloud computing as defined by the National Institute of Standards and Technology (NIST)  Self-service on demand  Access to a large network  Pooling of resources  Elasticity in a Hurry  Service that is measured Six fundamental qualities of cloud computing as defined by ISO 17788  Self-service on demand  Access to a large network  Pooling of resources  Elasticity in a Hurry  Service that is measured  Multi-tenancy is a term that refers to a situation 12 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 1.4Characteristics of cloud computing Self-service on demand: Email, Application Network, and Server services may all be delivered without requiring contact with each service provider. Self-service refers to when a customer completes all of the steps required to obtain a service without having to go into an IT department. For example, the consumer's request is then handled automatically by that of the cloud infrastructure, without any need for human interaction on the provider's part. Access to larger network: Cloud services are accessible over the internet and may be accessed using a standard mechanism that allows for usage by a variety of clients, including mobile phones and laptops. Pooling of resources Different physical and virtual resources can be dynamically allocated and reallocated according to the customers' need, with the provider's computer capabilities pooled together to serve numerous clients. 13 CU IDOL SELF LEARNING MATERIAL (SLM)

a. The client has no control or knowledge of the specific location of the delivered resources, but may be able to define location at such a different level of abstraction (e.g.,country, state, or datacenter). a. Storage, computation, memory, as well as network bandwidth are examples of resources. Elasticity in a Hurry Capabilities may be provided and released flexibly, and in some circumstances automatically, to scale outward and inward in response to demand. To the customer, provisioning capabilities frequently appear to be limitless, and they may be used in whatever quantity at a certain time. Service that is measured: Cloud systems utilize a metering capability at a level of abstraction suited to the type of service to automatically regulate and optimize resource utilization (e.g., storage, processing, bandwidth, and active use account). – Resource utilization may be tracked, regulated, and reported, giving both the supplier and the user of the service complete transparency. Multi-tenancy: Customers, also known as tenants, in a private cloud might have distinct business divisions within the same corporation. Customers in a public cloud are frequently from various companies. The multi-tenancy approach is used by the majority of public cloud providers. Multi-tenancy allows users to share a single server instance, saving money and making it easier to roll out changes to the large number of clients. 1.6BENEFITS OF CLOUD COMPUTING The benefits of cloud computing are numerous. The following are a few of them: 14 a. Applications as utilities can be accessed over the Internet. b. At any moment, manipulate and adjust the program online. c. Accessing or manipulating cloud applications does not necessitate the installation of any specialized software. d. The Platform as a Service paradigm of cloud computing provides online development and deployment tools, as well as a programming runtime environment. e. Cloud resources are made available across the network in a way that allows any sort of client to access them regardless of platform. CU IDOL SELF LEARNING MATERIAL (SLM)

f. Cloud computing enables self-service on demand. Without interacting with the cloud service provider, the resources can be utilized. g. Cloud computing is extremely cost-effective since it runs at higher efficiency and utilizes resources more effectively. All you need is an Internet connection. h. Load balancing is a feature of cloud computing that makes it more dependable. Figure 1.5 Benefits of Cloud Computing 1.7CLOUD COMPUTING VS CLOUD SERVICES That's the main distinction: cloud services are programs that are fully functional end-user apps. Cloud computing refers to the ability to rent computing infrastructure and services. Unless your organization generates software for a livelihood, you should focus on SaaS (cloud service) rather than cloud computing if you're in business. We give two tables in this part that demonstrate the distinctions and key characteristics between cloud computing vs cloud services (Jens, 2008). Cloud computing is it's The basis for cloud services, and it comprises of cloud-enabling technologies. Table 1.1 lists the fundamental characteristics of cloud computing. In Table 1.2 summarizes the key characteristics of cloud services (Jens, 2008). Table 1.1 Key Cloud Computing Attributes (adapted from Jens (2008)) Attributes Description Infrastructure systems It includes servers, storage, and networks 15 CU IDOL SELF LEARNING MATERIAL (SLM)

Application software that can scale as per user demand. It provides Web-based user interface, Web Application development and deployment services APIs, and a rich variety of software configurations System and application management It supports the development and integration software of cloud application software IP networks It supports rapid self-service provisioning and configuration and usage monitoring. They connect end users to the cloud and the infrastructure components Table 1.2 Key Attributes of Cloud Services (adapted from Jens (2008)) Attributes Description Offsite. Third-party provider In the cloud execution, it is assumed that third-party provides services. There is also a Accessed via the Internet possibility of in-house cloud service delivery Services are accessed via standard-based, Minimal or no IT skill required universal network access. It can also include Provisioning security and quality-of-service options. There is a simplified specification of Pricing requirements. User interface It includes self-service requesting, near real- System interface time deployment, and dynamic and fine- grained scaling Shared resources Pricing is based on usage-based capability and it is fine-grained. User interface include browsers for a variety of devices and with rich capabilities. System interfaces are based on Web services APIs providing a standard framework for accessing and integrating among cloud services. Resources are shared among cloud services users; however, via configuration options with the service, there is the ability to customize. 1.8SUMMARY  We examined the vision and prospects of cloud computing, as well as its characteristics and problems, in this chapter. The maturation and convergence of 16 CU IDOL SELF LEARNING MATERIAL (SLM)

numerous supporting concepts and technologies gave rise to the cloud computing paradigm.On the cloud phenomena, there is no one point of view. We look at several definitions, interpretations, and applications of this concept throughout the book. The one thing that all of these distinct perspectives on cloud computing have in common is that they all offer dynamic provisioning of IT services (whether virtual infrastructure, runtime environments, or application services) and use a utility-based pricing model to do it. Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), and Software-as-a-Service (SaaS) are the three key market sectors (and service offers) for cloud computing, according to the NIST model (SaaS). These parts directly mirror the general categories of the many types of cloud computing services.  Although this goal is still a long way off from being a reality, cloud computing has already offered financial, environmental, and technological advantages. Organizations may lower operational expenses and enhance income by converting IT assets into utilities. This, like other advantages, comes with a variety of drawbacks. Cloud computing brings together a diverse set of technologies, but harnessing these is a difficult technical endeavour. Cloud computing opens up new possibilities for software application and system architecture, as well as new methodologies and methods. 1.9KEYWORDS  Cloud Computing: cloud computing is the transmission of computer services over the Internet (“the cloud”) in order to provide speedier innovation, more flexible resources, and economies of scale.  SaaS: SaaS is a software distribution paradigm wherein the cloud provider hosts program then make them accessible to end customers through the internet.  PaaS:Platform as a service (PaaS) is really a cloud computing concept in which consumers get hardware and software tools from a third-party supplier through the internet.  IaaS:Infrastructure as a service (IaaS) is a pay-as-you-go cloud computing service that provides critical computation, storage, and networking resources on demand.  NIST: The National Institute of Standards and Technology 1.10LEARNING ACTIVITY 1. Explore some of the popularly used cloud computing services. 17 CU IDOL SELF LEARNING MATERIAL (SLM)

2. Suppose you are planning to utilize the cloud service for your organization core systems. Is it always available whenever and wherever you need to access? 1.11UNIT END QUESTIONS A. Descriptive Questions Short questions 1. What is the innovative characteristic of cloud computing? 2. Define cloud computing and identify its core features. 3.What is virtualization? 4. What is the major advantage of cloud computing? 5. What is Cloud and Cloud computing? Long Questions 1. What are the benefits and pitfalls of Cloud Computing?Brief it. 2. What is a cloud service? 3. Is Gmail a PaaS or SaaS? 4. Is Google Drive a cloud? Give detailed view on it. 5. List out the fundamental qualities of cloud computing which are defined by ISO 17788 B. Multiple Choice Questions 1. What type of computing technology refers to services and applications that typically run on a distributed network through virtualized resources? a. Distributed Computing b. Cloud Computing c. Soft Computing d. Parallel Computing 2. Cloud computing is a kind of abstraction which is based on the notion of combining physical resources and represents them as _______resources to users. a. Real b. cloud c. virtual d. None of these 18 CU IDOL SELF LEARNING MATERIAL (SLM)

3. Which one of the following cloud concepts is related to sharing and pooling the resources? a. Polymorphism b. Virtualization c. abstraction d. None of these 4. Which of the following is an essential concept related to Cloud? a. Reliability b. Abstraction c. Productivity d. All of these 5. Which one of the following is Cloud Platform by Amazon? a. Azure b. AWS c. Cloudera d. Cloude Answers 1-b, 2-c, 3-b, 4-b, 5-b 1.12REFERENCES Reference books  Rajkumar Buyya, Christian Vecchiola, S. Thamarai Selvi, “Mastering Cloud Computing”  Kailash Jayaswal, Jagannath Kallakuruchi, Donald J. Houde, Dr. Devan Shah, “Cloud Computing: Black Book  Cloud Computing: Principles and Paradigms, Editors: Rajkumar Buyya, James Broberg, Andrzej M. Goscinski, Wile, 2011.  Cloud_computing_for_energy_management_in_smart_gri.pdf Websites:  https://timesofcloud.com/cloud-tutorial/characteristics-of-cloud-computing-as-per- nist/ 19 CU IDOL SELF LEARNING MATERIAL (SLM)

20 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT2 - LAYERS IN CLOUD COMPUTING STRUCTURE 2.0 Learning Objectives 2.1 Introduction 2.2 Layers in Cloud Computing 2.3 SaaS 2.4 PaaS 2.5 IaaS 2.6 DBaaS 2.7 BPaaS 2.8 Summary 2.9 Keywords 2.10Learning Activity 2.11Unit End Questions 2.12 References 2.0LEARNING OBJECTIVES After studying this unit students will be able to:  Describe basic concepts of layers in cloud computing  Analyze how the SaaS- Software as a Serviceperforming in cloud layers  IllustratePaaS- Processas a Service functioning in cloud layers  Outline IaaS- Infrastructure as a Service in cloud computing  Describe details of DBaaS in Cloud computing  ExploreBPaaS in Cloud computing 2.1INTRODUCTION The storage and access of data and computer services through the internet is referred to as cloud computing. It does not save any information on your computer. It refers to the availability of computer services such as servers, data storage, networking, databases, and so on demand. The basic goal of cloud computing is to provide numerous users with access to data centers. Data from a distant server can also be accessed by users. Cloud computing, 21 CU IDOL SELF LEARNING MATERIAL (SLM)

rather than being a technology, is a business model. That is to say, there is no new hardware or software that has suddenly made cloud conceivable. Rather, it is made up of well-known technology and concepts that have been combined in a novel way. Layers are the technical terms for these technologies. We acquire the bundle that permits cloud by combining them all. The layers are explained deeply in this unit. 2.2LAYERS IN CLOUD COMPUTING Figure 2.1 shows the cloud computing layers.The three types of services available in the layers are as follows:  SaaS-Software as a Service  PaaS-Platform as a Service  IaaS-Infrastructure as a Service The detailed explanation of each of these service types will explained in further sections. Figure 2.1cloud computing Layers 22 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.2 The cloud computing architecture. Figure from (Zhang et al, 2010). As shown in figure 2.2 the cloud computing architecture divided into 4 layers. Those layers are:  Hardware layer  Infrastructure layer  Platform Layer  Application Layer It supports three service models which are described in detail in further sections. 2.3 SAAS: SOFTWARE AS A SERVICE Software as a service (SaaS) is software which is publicly stored and maintained for the benefit of the end user. It's frequently built on a multitenant architecture, which means that all clients get the same version of the program. It may be scaled up to many instances to provide optimal performance across all locations. The majority of SaaS software is licensed on a monthly or yearly basis. Office 365 is a good example of a SaaS solution. Subscribers can obtain Enterprise as a Service (online and/or personal computers Outlook), Storage as a Service (OneDrive), as well as the rest of the Microsoft Office Suite for a monthly or annual price (online, the desktop version, or both). The latest version is always offered to subscribers. This effectively lets users to have a MS Sql server without buying a server, install Exchange, and support it—the Exchange server is 23 CU IDOL SELF LEARNING MATERIAL (SLM)

handled for customers, with software patches and upgrades. This is far less expensive and needs far less effort to maintain up to date than installing and upgrading Office every year. Microsoft One Drive, Dropbox, WordPress, and Amazon Kindle are all instances of SaaS. Figure 2.3Saas application definition A browser or an app can be used to access a SaaS application. SaaS applications include email service apps that users can access via a web page, like Gmail and Office 365.As shown in figure 2.3 The distinction between SaaS and installing software on a user's PC is similar to the difference between watching a Show on web and buying all of the seasons on DVD. Figure 2.4Users can access Saas app on any device A customer who owned a TV show on DVD only has to pay once; nevertheless, they must store and preserve the DVDs, and if their hardware changes — for example, if their DVD player is replaced with such a Blu-ray player – they must purchase the digital files again. Instead, by streaming the show, a third company handles all of the storage and updates, leaving the consumer with nothing to do but push play. Streaming, on the other hand, is reliant on to a Connection to the internet, and consumers are often forced to pay a monthly service price to keep their access. Advantages of using SaaS a. This provides a lot of flexibility for businesses: 24 CU IDOL SELF LEARNING MATERIAL (SLM)

Users may often log into SaaS apps from every device and from any place. workers may wor k from anywhere in the globe, and users may access their information from anywhere. Furthermore, most users have many devices and swap them out frequently; they shouldn't nee d to update SaaS programmes or buy new licences every time they transfer devices.  There are no updates or installs required:  The programme is updated and patched on a regular basis by the SaaS provider.  Scalability: As the application's usage grows, the SaaS provider manages scaling it up , such as adding extra database space or computing capacity.  SaaS saves money by reducing internal IT expenditures and overhead. The application 's servers and infrastructure are maintained by the SaaS provider, and the only expense to a firm is the application's subscription fee. Disadvantages: Stronger access control is required: The rising accessibility of SaaS services necessitates the verification of user identification an d the management of access levels. Organizational assets are no longer retained within an internal network, isolated from the rest of the world, with SaaS. User access is instead provided based on user identity: If a user has the correct login credentials, they will be permitted access. As a result, strong identity verification becomes critical. Vendor lock-in: A company's reliance on a SaaS application provider may become excessive. When organization's existing system is kept within the old application, migrating to a new application is time-consuming and costly. Security and compliance: Using SaaS applications, the duty for securing the programmes an d the data they contain shifts from internal IT teams to external SaaS providers. That is much less of a drawback for small and mediumsized enterprises, as bigger cloud services often have greater resources for putting effective security in place. However, if a major company is subject to stringent security or regulatory requirements, this might be difficult. In certain circumstances, organisations will be unable to examine the security of their apps on their own , such as tthrough penetration testing. They must rely on the outside SaaS provider's assurances that the programme is safe. 25 CU IDOL SELF LEARNING MATERIAL (SLM)

2.4PAAS: PLATFORM AS A SERVICE With PaaS, users deploy their application onto a cloud service vendor's application-hosting environment. The developer creates the software, and the PaaS provider makes it possible to deploy and operate it. Developers are freed from infrastructure administration, allowing them to concentrate only on development. Azure Websites and Azure Cloud Services are only two of the PaaS computing options available (web and worker roles). In any scenario, developers have a variety of options for deploying their application without having to understand the nuts and bolts that enable it. Developers do not need to construct virtual machines (VMs), connect into each one using Remote Desktop (RDP), and deploy the program. They simply press a button (or something similar to it), and Microsoft's tools setup the VMs, then distribute and install the program on them. In most cases, scaling up an Azure computing service is as easy as increasing the instance count, after which Azure creates additional VMs and installs the software on them. Even the load balancing is handled automatically by Azure. To deploy a new version, just republish, and Azure will automatically update all of their VMs. Vendors providing PaaS services often include the following features:  Tools for development  Middleware is a term used to describe software that  Computer operating systems  Database administration  Infrastructural development  Other services may be included by different suppliers, and these are the main PaaS features. Tools for development PaaS companies provide a range of software development tools, such as a code editor, a debugging, a translator, and other necessary tools. These tools might be used to form a framework. The tools available will vary depending on the provider, but PaaS should provide anything a lead to scope to construct their project. Middleware Middleware is frequently included in platform-as-a-service offerings such that developers wouldn't have to create it themselves. Middleware is technology that lies between user-facing programs and the operating system of the machine; for example, middleware allows software 26 CU IDOL SELF LEARNING MATERIAL (SLM)

to get information to the computer and mouse. Although middleware is required to execute an application, end users do not interact with it. Computer operating systems The operating system on which developers work as well as the application runs will be provided and maintained by a PaaS vendor. Database administration Databases are managed and maintained by PaaS providers. They will almost always give a database model to developers as well. Infrastructural development There in cloud computing paradigm (Figure 1.1), PaaS will be the next tier up from IaaS, and it includes everything that IaaS does. Servers, storage, including physical data centers are either managed by a PaaS provider or purchased with an IaaS provider. Advantages: Faster time to market: PaaS allows developers to build applications faster than they could if they had to create, configure, and deploy their native platforms and backend technology. All they have to do with PaaS is develop the code as well as install applications, and the vendor will take care of the rest. From beginning to end, there is just one environment: PaaS allows developers to create, debug, test, publish, run, and update their apps all in the same place. This allows developers to ensure that a web application will work effectively as a hosted application before releasing it, as well as simplifying the application development process. Price: In many circumstances, PaaS is much more cost-effective than utilizing IaaS. PaaS clients save money since they don't have to manage or deploy virtual machines. Furthermore, some vendors provide a pay-as-you-go pricing model, wherein the vendor just charges for the computer resources used by the programmer, saving clients money. However, each vendor's pricing structure varies significantly, and maybe some platform providers demand a monthly fixed cost. Licenses is simple: PaaS providers manage all operating system, development tool, and other platform licensing. Disadvantages: The following are some of the potential pitfalls of adopting PaaS: 27 CU IDOL SELF LEARNING MATERIAL (SLM)

Lock-in of vendors: Because the application is designed when using vendor's tools and expressly for their platform, switching PaaS providers may be difficult. Each vendor's architectural requirements may differ. Technologies, libraries, APIs, architecture, and operating systems used to construct and run the application may not be supported by all suppliers. Switching suppliers may need rebuilding or significantly altering a program. Dependence on a vendor: Companies may become more reliant on their present PaaS vendor due to the time and resources required to switch suppliers. A little modification with in vendor's internal procedures or infrastructure might have a significant impact on the performance of such an application that was supposed to function smoothly on the previous setup. Furthermore, if the vendor's pricing strategy changes, an application's operating costs may increase dramatically. Security and compliance issues: In a PaaS design, an external vendor would store the majority or the whole of an app's data as well as host its code. In other circumstances, the vendor may store the databases through a third-party source, such as an IaaS provider. Despite the fact that most PaaS suppliers are huge corporations with robust security, it is impossible to properly examine and evaluate the security measures safeguarding the application as well as its data. Furthermore, for businesses that must adhere to stringent data security standards, certifying the compliance of extra external vendors would add to the time it takes to get to market. 2.5IAAS: INFRASTRUCTURE AS A SERVICE Infrastructure-as-a-Service (IaaS) The service gives users access to basic resources including real machines, virtual computers, virtual storage, and so on. In addition to such resources, the IaaS provides:  Disk storage for virtual machines  Local area network (VLANs)  Load balancers are a type of load balancer that is used to distribute  IP addresses are numbers that are assigned to computers.  Bundles of software Server virtualization makes all of the aforementioned resources available to end users. Furthermore, clients have access to these resources as if they were their own. 28 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.5Infrastructure as a Service IaaS makes it possible for users’ provider to cost-effectively and flexibly locate infrastructure over the Internet. The following are some of the major advantages of IaaS: Makes administration to VMs gives you complete control over the computing resources. IaaS gives customers administrator access to virtual machines, allowing them to utilize computing resources in the following ways: The customer gives the cloud provider administrative commands to launch the virtual machine or save data on the cloud server. Customers use administrator commands to launch web servers or install new apps on virtual machines they control.  IaaS resources like virtual computers, disk drives, connectivity, IP addresses, surveillance systems, firewalls, and other IaaS resources are made accessible to consumers on a rental basis. The fee is calculated based on how long the consumer keeps a resource. The customer may also run any program, including a custom operating system, on virtual machines with administrative privileges.  Heritage application portability and interoperability:It is feasible to retain legacy across apps and workloads across IaaS clouds. Network applications like web servers and e-mail servers, which are typically hosted on customer-owned server hardware, may now be run from VMs in the IaaS cloud. 29 CU IDOL SELF LEARNING MATERIAL (SLM)

Disadvantages: Compatibility to legacy security flaws: Because IaaS allows customers to run legacy software on the provider's infrastructure, consumers are exposed to all of the legacy software's security flaws. Expansion of virtual machines: Because IaaS allows customers to run virtual machines in a running, suspended, or off state, the VM may become out-of-date in terms of security upgrades. Nevertheless, the provider can update such VMs automatically, although this technique is difficult and complex. Isolation at the VM level is robust: Through hypervisor, IaaS provides an isolated environment for individual consumers. A hypervisor is a software layer that contains hardware support for virtualization, which allows a real computer to be divided into several virtual computers. Practices of data erasure: The client employs virtual machines, which in turn use the cloud provider's shared disc resources. When a client leaves a resource, a cloud provider must guarantee that the next customer using the resource does not see any data left over from the prior tenant. 2.6DBAAS- DATABASE-AS-A-SERVICE Database-as-a-Service (DBaaS) is just a cloud computing service that enables businesses to access databases without having to set up physical infrastructure. Users also don't have to install software or engage people to keep the underlying technology up to date. With one-click operations, DBaaS simplifies database maintenance, reduces time-consuming procedures, and allows for speedier software development. The database server is often part of the on-premises computer infrastructure in a conventional architecture. The database must be installed, managed, protected, and scaled by the local team. DBaaS, on the other hand, is indeed a subscription service wherein the provider handles the hardware and makes the database available as just a private cloud service. The high-level database administrative (DBA) activities are handled by the service provider, which include: a. The first instalment. b. Management of configurations. c. Upkeep of the database. d. Management of performance. e. Backups are important. 30 CU IDOL SELF LEARNING MATERIAL (SLM)

f. Patches and upgrades are available. g. Recovery from a disaster. h. Monitoring in the cloud (both for the database and the underlying infrastructure). i. Keeping a high level of availability The sole obligations of a DBaaS customer are to use the database and manage its content. If the firm wants more control over the database, the DBaaS provider can allow for additional user participation. The managed database service is another term for DBaaS. Both relational and non-relational databases are covered by this form of cloud service. Figure 2.6Database as a Service DBaaS eliminates the need to employ and train a database management crew. Instead, the database instances are managed by a single employee using an API and a management dashboard. The dashboard simplifies complicated procedures like provisioning and specification by allowing one-click actions. The DBaaS platform provisions the database and delivers a query-able endpoint after the console gets instructions from the user. This code can be entered directly into the programby the user. Database-as-a-ServiceUsers may operate a database using a common set of abstractions (primitives) without having to understand the implementations. For example, regardless of the database type, a developer might add a database instance using the same set of API 31 CU IDOL SELF LEARNING MATERIAL (SLM)

methods (MongoDB, Oracle, MySQL, etc.). Simple mechanics are also provided by the DBaaS concept for:  Users are being added.  Schemas are being created.  Permissions are granted.  Keeping track of your activities. There are two main users of Database-as-a-Service: a. Cloud management and maintenance organizations. b. Teams who make use of cloud resources (either traditional development or DevOps teams). Small to medium-sized businesses without large IT operations will benefit from DBaaS. Smaller teams can design programs that they couldn't afford to operate on-premises since the DBaaS takes on the financial load of hardware and maintenance. DBaaS systems are also used by businesses to support certain releases or limit the configurations that customers can supply. For example, a corporation can limit developers to using standard hard drives for provisioning. Meanwhile, DevOps engineers may be able to use SSDs to provision larger capacity servers.Due to the hazards of keeping data in the cloud, databases processing data having tight legal standards are not suited for DBaaS. In-house infrastructures are also a better option for mission-critical applications that require 99.999 percent uptime. 32 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.7on-premise Database vs DBaaS Setting up DBaaS: A cloud service as well as a database service are required to set up DBaaS. Amazon AWS, Microsoft Azure, Oracle Cloud, Google Cloud Platform, as well as phoenixNAP Bare Metal Cloud are all popular cloud providers. The following are the most common DBaaS providers: i) Amazon.com (Amazon Aurora, DynamoDB, Amazon RDS, SimpleDB) ii) Cloud by Google (GC Bigtable, Google Cloud Datastore, GC Spanner, Google Cloud SQL) iii) Microsoft Azure is a cloud computing platform developed by Microsoft (Microsoft SQL Database, MA Table Storage, Microsoft DocumentDB) iv) compose (IBM) v) Cloudant, IBM vi) Atlas of MongoDB vii) Oracle Cloud Database Service It is not necessary for the cloud and database services to be provided by the same company. A team may, for example, build up Bare Metal Cloud for cloud needs and link it with Microsoft's SQL Server database. However, not all cloud platforms offer all database management systems (DBMS), so do your homework before mixing and matching providers. Benefits: Figure 2.8Business Benefits of DBaaS 33 CU IDOL SELF LEARNING MATERIAL (SLM)

Developer Agility: Standard database deployment is a multi-step, complicated procedure that necessitates a number of actions. The following is an example of a typical deployment: i) In the ticketing system, a developer submits a request. ii) The ticket remains throughout the queue when it is moved to the top of the list of priorities. iii) The ticket is assessed by the IT department. iv) If the request is valid, the team allocates the new database's computing, storage, and networking resources. v) Start configuring resources and installing software. vi) The developer obtains database entry point and proceeds to utilize the new configuration. This is not an agile method, particularly unless the team is attempting to shift to DevOps. This method of database deployment is both error-prone and time-consuming.The DBaaS approach automates the deployment process and requires no IT involvement. The firm creates a database provisioning standard, following which the deployment is handled by a developer. IT administrators may concentrate on more important responsibilities, while developers may quickly set up an integrate a database. More IT Productivity: The team is responsible for database tuning, monitoring, patching, updating, and resizing as part of standard database maintenance. The numbers and variety of databases that need to be managed grow as firms develop, making these activities even more time-consuming. The team saves time using DBaaS because:  The majority of administrative tasks are handled by the supplier.  Complex operations (such as deployments, upgrades, and configuration changes) are carried out automatically.  With a single command, developers may create and destroy many databases. The team can focus on more significant responsibilities, such as designing apps and inventing, because they don't have to deal with repetitive activities or micromanagement. Application Security: The majority of cloud database vendors provide enterprise-level security. The following are some of the features that a good service will give to secure your databases: i) Encrypting data (both at rest and in transit). 34 CU IDOL SELF LEARNING MATERIAL (SLM)

ii) Access control that is integrated. iii) Controls for ensuring regulatory compliance. iv) virtual private networks provide end-to-end network security. Data loss is less likely as a result of high-level security. Furthermore, every major cloud provider offers a service-level agreement (SLA) which ensures uptime. Cost Savings: Database-as-a-Service is a less expensive option to building your own database. DBaaS allows a business can pay a predictable monthly cost depending on the resources used. A company saves money by just not having to spend money on: i) Hardware that is both expensive and power demanding. ii) Data centers are places where information is stored. iii) Licensing of software. iv) Additional storage space. v) Infrastructure management and maintenance by qualified personnel. Database-as-a-Service in addition, service avoids wasting resources. Users, like any other cloud service, have control over how much resources they utilize, allowing a company to assure optimal usage at all times. Better reliability and performance: DBaaS solutions are highly available and function at their best. The technology reroutes traffic to something like a duplicate in the event of a breakdown, ensuring uptime. Scalability is a strong suit of Database-as-a-Service. To satisfy high processing needs, users can boost storage and computer capacity fast and simply. It's also simple to reduce use during off-peak hours. This flexibility is suitable for dynamic database needs like end-of-quarter reporting and seasonal e-shopping spikes. DBaaS disadvantages: Lack of control:Internal employees has never had access to the database's servers or storage. If the user's connectivity falls down or perhaps the provider goes down, the customer will be unable to access the saved material. Concerns about security: Storing data on the cloud might lead to a data breach unless the provider isn't attentive. Furthermore, the physical security of servers is unaffected by the customer firm. Latency issues: Using the internet to access data might cause performance problems, especially when loading huge volumes of data. 35 CU IDOL SELF LEARNING MATERIAL (SLM)

2.7BPAAS- BUSINESS PROCESS AS A SERVICE Business process as a service, or BPaaS, is a sort of business process outsourcing (BPO) that is supplied over the cloud. BPaaS is extensively flexible and connects to other services such as SaaS, PaaS, and IaaS. By leveraging the flexibility and productivity of a cloud-based system, BPaaS offers businesses with the people, processes, as well as technology it will need operate as just a pay-per-use service. By delivering an on-demand solution depending on services required rather than purchasing a package deal related to a particular application, this approach to operations dramatically minimizes total cost of ownership. BPaaS allows businesses to stay on top of industry best practices and technological innovations. With BPaaS's distinct business flexibility and agility, companies can simply enhance service levels throughout peak periods and bring innovative product and services into market faster. Benefits: BPaaS has a number of advantages for businesses, including: Product/service deliverability: BPaaS uses cloud technology to assist business provide services and products in an automated, efficient manner, from controlling inventories to organizing email and customer information. Because BPaaS is standardized for usage across sectors and organizations, it is adaptable and repeatable, leading in increased productivity and, as a consequence, improved customer service and experience. Cutting-edge technology at a lower cost: BPaaS offers a firm with the most up-to-date digital tools, technologies, processes, and people to increase efficiency, service, and the customer experience without the substantial capital expenditure necessary in the past. Companies may move to something like a pay-per-use model based and lower cost of ownership by using BPaaS. Adapts to changing business needs:When a company's workload spikes, BPaaS can grow on-demand. The service may leverage its cloud basis to expand to address big swings in business process demands due to its inherent configurability applicable across many business domains and its connection with other fundamental cloud services like SaaS. Along with the obvious economic benefits as well as ease-of-use with delivering BPaaS from the cloud, a key benefit I see moving forward is the ability for a prospective user to take it for a test drive, that really is, users could indeed attempt out different services before integrating them into their larger business processes or quickly replacing an existing service. Virtual desktop principles make these services accessible from any device. This is a total paradigm change that everyone, even internal IT departments, will have to adjust to; IT teams are no longer the ones that create and source services. Line-of-business executives may now search for services in the market place, test them out, and then decide whether to buy or keep exploring for something else. The services used by business process could be sourced from 36 CU IDOL SELF LEARNING MATERIAL (SLM)

an internal private cloud, a partner's cloud, or a public cloud, as shown in Figure 2.9. A BPaaS via cloud delivery paradigm, on the other hand, provides totally new markets for enterprises and CIO organizations when conventional delivery methods do not provide access to such markets. They should, I suppose, answer them the following questions:  What distinguishes a successful cloud provider business strategy as well as model?  How might collaborating throughout the ecosystem help me achieve greater success?  What are the consequences if I do nothing now? Figure 2.9 Internal and external services Let's take a look at IBM Blue works Live, which is an instance of a BPaaS product. Blue works Live seems to be an offering which helps bring everyone else in the process conversation, resulting in increased visibility and much more consistent results, either they are engaged in simple processes that are currently run over email, having managed a small team and would like to run more efficiently, or involved in a corporate BPM program around process modelling and governing. The following are the primary enterprise BPM capabilities that Blue works Live offers. Why Business need Cloud-based BPaaS? A business process service can be linked to a number of services, such as SaaS (Software as a Service) applications, PaaS (Platform as a Service) environments, as well as IaaS (Infrastructure as a Service) (Infrastructure as a Service). An analytic process service, for example, may be created to evaluate data from a number of CRM and social media platforms. 37 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 2.10Cloud Based BPaas The term \"cloud computing\" refers to a mechanism for tracking system resources. This allows service providers to charge users using network, storage, as well as processing services based on their specific needs. It enables organizations to safely store data on the internet. The firm is free of uncertainty since its automated services take care of every aspect. There are no servers to buy or maintain, therefore costs are kept to a minimum. As there are no geographical restrictions to getting solutions, they are more adaptable. It is considerably easier to improve business services. Companies may now add new features to their offerings without incurring significant infrastructure costs. As related services, cloud encompasses (SaaS), (PaaS), and (IaaS), from which organizations may select the platform that best matches their needs. Payroll and shipping services, for example, are better handled with SaaS to ensure that such complicated procedures are handled quickly. The benefits of cloud computing are numerous, and BPaaS, with its service-oriented design and well-defined interfaces, is improving its market applicability. No other business process employs BPaaS, which is a standardized service that fits with the three core cloud services we discussed earlier: SaaS, PaaS, and IaaS. It aids in the automation of activities while maintaining a high level of security, making it a must-have for businesses. 2.8SUMMARY  Cloud computing is an emerging computing paradigm that provides the general public with massive amounts of computational and storage resources. Individuals (for example, scientists) and businesses (for example, startup firms) can gain access to the information by paying a nominal fee just for what they require. 38 CU IDOL SELF LEARNING MATERIAL (SLM)

 The main objective of this chapter is to make us clearly understand the design principles of cloud computing layers.The outline of the cloud layers also helps us to makethe right decision in designing and choosing the cloud for the business. The concept of SaaS, IaaS, PaaS, DBaaS and BPaas are clearly explained. The benefits of each (SaaS, PaaS, IaaS, BPaaS, DBaaS)service in the cloud has been explained briefly. We will discuss types of cloud in the next chapter. 2.9 KEYWORDS  DBaaS- Database as a service (DBaaS) is a cloud computing managed service offering that provides access to a database  BPaaS -Business Process as a Service (BPaaS) is a cloud computing service paradigm for business process outsourcing (BPO). Unlike standard BPO, which aims to lower labor costs by increasing automation, BPaaS aims to lower labour expenses by reducing labor count.  BPM - Business process management (BPM) is a discipline that involves examining a business process, modelling how it works in multiple circumstances, implementing improvements, and continuously enhancing it. 2.10 LEARNING ACTIVITY 1. Suppose you are using a cloud computing platform, what are the most important considerations for you before using it? 2. If your organization has conducted a business case and the results indicate that we should go to the cloud, So, from top to bottom, what are the major successful factors to examine the advantages and disadvantages of? 3. Assume you're beginning a new video analysis company. You'll need to have a lot of storage because videos take up a lot of space. You'll also need a lot of computing power to run multiple applications at the same time. You've identified some excellent tools for making development easier on Windows, but deployment will be done more effectively in the Linux environment. You should move to the cloud, according to all the arrows. You've discovered that SaaS is the most appealing service, following by PaaS and IaaS. Which service would you suggest based on the information above? Why? 39 CU IDOL SELF LEARNING MATERIAL (SLM)

2.11 UNIT END QUESTIONS A. Descriptive Questions Short Questions 1. How does PaaS compare to development environments that are hosted internally? 2. What does PaaS entail? 3. What are the benefits of PaaS for developers? 4. Can you name a few of the most widely utilized cloud computing services?Explain everything in detail. 5. What is cloud computing's many layers? Explain everything in detail. Long Questions 1. Examine the differences among cloud and on-premise computing. 2. Make a list of the advantages of utilizing DBaaS in the workplace. 3. Describe the various types of software as a service (SaaS). 4. What is the value of the platform as a service? 5. What are all the resources that an infrastructure as a service provides? B. Multiple choice questions 1. The SaaS software is licensed on _____basis. a. monthly b. daily c. weekly d. hourly 2. Which of the following is not considered as advantages of using SaaS. a. Scalability b. Flexibility c. Saves money d. Updates required 3. Which of the following are disadvantages of adopting paaS? a. Lock-in of vendors b. Dependence on a vendor c. Security and compliance issues d. All of these 40 CU IDOL SELF LEARNING MATERIAL (SLM)

4. ________is just a cloud computing service that enables businesses to access databases without having to set up physical infrastructure. a. DBaaS b. PaaS c. IaaS d. SECaaS 5. BPO stands for a. business process outsourcing b. business planningoutsources c. business process outcome d. business process outdates Answers 1-a, 2-d, 3-d, 4-a, 5-a. 2.12 REFERENCES Reference books  Rajkumar Buyya, Christian Vecchiola, S. Thamarai Selvi, “Mastering Cloud Computing”  Kailash Jayaswal, Jagannath Kallakuruchi, Donald J. Houde, Dr. Devan Shah, “Cloud Computing: Black Book  Cloud Computing: Principles and Paradigms, Editors: Rajkumar Buyya, James Broberg, Andrzej M. Goscinski, Wile, 2011.  Cloud_computing_for_energy_management_in_smart_gri.pdf Websites:  https://timesofcloud.com/cloud-tutorial/characteristics-of-cloud-computing-as-per-nist/  https://www.dummies.com/programming/cloud-computing/hybrid-cloud/how-bpaas- works-in-the-real-world-of-cloud-computing/  https://cyfuture.com/blog/cloud-based-bpaas-all-you-need-to-know/ 41 CU IDOL SELF LEARNING MATERIAL (SLM)

UNIT3 -TYPES OF CLOUD COMPUTING STRUCTURE 3.0 Learning Objectives 3.1 Introduction 3.2 Types of Cloud 3.3 Public cloud 3.4 Private Cloud 3.5 hybrid cloud 3.6 Community Cloud 3.7 Compare cloud computing with traditional client/server architecture 3.8 Pros and cons of Cloud computing 3.9 Key technologies 3.10Summary 3.11 Keywords 3.12Learning activity 3.13Unit End Questions 3.14 References 3.0LEARNINGOBJECTIVES After studying this unit students will be able to:  Outline types of cloud and its importance,  Comparetraditional computing with cloud computing  Describe Pros and cons of using cloud computing.  Describekey enabling technologies in cloud computing. 3.1 INTRODUCTION Cloud computing is a viable replacement for on-premises datacenters. We must manage everything with an on-premises datacenter, including acquiring as well as installing hardware, virtualization, deploying the operating system and any other essential program, configuring the network, establishing the firewall, and configuring data storage. After we've completed all of the setup, we're in charge of keeping it running for the rest of its life.There 42 CU IDOL SELF LEARNING MATERIAL (SLM)

are many distinct forms of cloud computing, and determining which one best meets each company's needs can be difficult.This chapter comes up with an introduction to how we can classify thetypes of clouds and how it is used effectively in the real world businesses. These cloud deployment models (types) differ in terms of implementation, hosting, and who gets access to them. Virtualization (the abstraction of resources from bare metal infrastructure) underpins all Cloud deployment options, although they vary in terms of geography, storage capacity, accessibility, and other factors. You'll want to evaluate Public, Private, Hybrid, and Community Clouds with terms of the varying levels of security they provide and the management necessary, depending on the type of data you're working with. 3.2TYPES OF CLOUD The basic output of cloud computing is clouds. They're a sort of parallel and distributed system that combines physical and virtual processors to form a single computing resource. Clouds provide the infrastructure for implementing and delivering services to customers. These infrastructures could be of many sorts and give essential information on the cloud's nature and services. A more practical categorization is based on a cloud's administrative domain: It defines the limits inside which cloud computing services were deployed, gives suggestions about the underlying infrastructure used to support them, and qualifies them. After then, as shown in figure 3.1 four main types of clouds may be distinguished: • Public Cloud: The cloud is available to the general public. • Private Clouds: The cloud is established within an institution's own premises and made available to everyone or a subset of the institution's members. • Hybrid or heterogeneous Clouds: The cloud is a hybrid of the two preceding options, and it most usually refers to a private cloud which has been supplemented with public cloud resources or services. 43 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 3.1Cloud Types • Community Clouds: The cloud is distinguished by only a multi-administrative domain that includes many deployment patterns (public, private, and hybrid) and is tailored to meet the demands of a particular sector. This classification may be applied to almost all cloud deployments. We'll give you a quick rundown of these clouds in the sections below. 3.3PUBLIC CLOUDS The earliest manifestation of cloud computing is public clouds. They are a manifestation of the standard cloud computing model, in which services were made available to anybody, from anywhere, at any time over the Internet. They are a distributed system from a structural standpoint, most likely made up from one or even more datacenters networked simultaneously, on base of which the cloud's specialized services are deployed. Any client may quickly sign up for cloud services, input her credentials and billing information, and utilize the services available. Public clouds were just the first type of cloud to be built and sold in the past. They provide cost-cutting IT infrastructure solutions as well as a realistic choice for coping with peak pressures on local infrastructure. They've grown in popularity as a viable choice for small firms who want to launch their company without making huge upfront expenditures by depending solely upon public infrastructure besides their IT needs. The freedom can grow / shrink per the demands of the linked business makes public clouds more appealing than reconfiguring private premises and purchasing gear and software. Customers were allowed can dynamically sell up or downsize their IT based on the demands of their business by renting infrastructure as well as subscribing to application services. Nowadays, public clouds are utilized to both totally replace and extend an enterprise's IT infrastructure as needed. Multitenancy is an important feature of public clouds. A public cloud was designed to service a large number of users rather than a single client. Any consumer wants a virtual computing environment which is independent from other users and, in most cases, isolated. This is a prerequisite for providing efficient user activity monitoring and ensuring the appropriate performance and other QoS parameters negotiated with users. The administration of Quality of Service (QoS) in public clouds is critical. As a result, a large percentage of its software infrastructure is dedicated to monitoring cloud resources, billing them according to the user's contract, and maintaining a detailed history about cloud usage for each client. These properties are relevant to overall clouds because they enable providers to give services to consumers while maintaining complete responsibility. Any type of service, such as infrastructure, platform, or apps, may be provided via a public cloud. For example, Amazon EC2 offers infrastructure as a service; Google AppEngine offers 44 CU IDOL SELF LEARNING MATERIAL (SLM)

the application development platform as a service; and SalesForce.com offers software as a service. What distinguishes public clouds is the manner in which they are consumed: They are open to the public and are often designed to handle a large number of users. Their innate capacity should scale upon demand and endure peak loads is what distinguishes them. From an architectural standpoint, there are no limitations on the sort of distributed system which can be used to support public clouds. The physical infrastructure upon which services are created and provided is most likely made up of one or more datacenters. Clouds in the public domaincan be made up of globally scattered datacenters to distribute user load and provide better service based on their location. Amazon Web Services, for example, offers datacenters in the United States, Europe, Singapore, & Australia, and clients may pick from three distinct regions: us-west-1, us-east-1, or eu-west-1. These areas are organized under availability zones, which correspond to certain datacenters, and are charged accordingly. A distinct software stack is deployed to administer the infrastructure depending on the type of cloud services delivered: virtual machine managers, distributed middleware, or distributed apps. 3.4PRIVATE CLOUD Although public clouds are enticing and offer a feasible solution for reducing IT costs and capital expenditures, they are not appropriate in all situations. For example, one of the most prevalent criticisms about cloud computing inside its classical form is indeed the lack of control. When it comes to public clouds, The supplier has control over the infrastructure as well as, eventually, the fundamental logic and sensitive data of the clients. Even if there is a legislative mechanism in place that ensures fair management and respect for the privacy of customers, this situation might be viewed as a threat or perhaps an unacceptable risk also that businesses are unwilling to take. Institutions like government and military organizations, in particular, will not contemplate using public clouds to handle or store sensitive data. The possibility of a breach in the provider's security infrastructure exposing this information to others might be judged undesirable. In other scenarios, losing control over where the virtual IT infrastructure lives might lead to a slew of additional issues. The rules that apply to the handling of digital information are often determined by the geographical location of such a datacenter. As a result, depending on the location of data, certain sensitive information might be made available to government authorities or even considered illegal if it is processed using particular cryptographic algorithms. For instance, the USA PATRIOT Act5 gives the government as well as other agencies nearly unrestricted access to information, including information held by any firm based in the United States. Finally, existing businesses with significant computer infrastructures or software installed bases do not just wish to transfer to public clouds; instead, they want to maximise their profitability by utilizing their current IT resources. 45 CU IDOL SELF LEARNING MATERIAL (SLM)

Because of these factors, using a public computer infrastructure is not always feasible. Nonetheless, the overall concept underpinning the cloud computing vision might be appealing. More particular, even when deployed within the private premises of such an organization, having an infrastructure capable of delivering IT services on demand may be a winning option. Private clouds, which are comparable to public clouds but have a resource- provisioning mechanism that is constrained inside an organization's bounds, have sprung out as a result of this concept. Private clouds were virtual distributed systems which run on even a private infrastructure and offer dynamic computing resource provisioning to internal users. Other strategies could be in place, keeping in mind cloud usage and proportionately paying different departments or divisions of a company, rather to a pay-as-you-go approach like in public clouds. By relying on existing IT infrastructure and lowering the cost of maintaining it after the cloud is set up, private clouds have the benefit of keeping key business processes in-house. Because sensitive data does not travel out from the private infrastructure, security issues are less pressing in this case. Furthermore, so the private cloud may supply services to a diverse variety of consumers, current IT resources may be better utilized. Another intriguing benefit of private clouds is the ability to test apps and systems at a cheaper cost than public clouds before putting those mostly on public virtual infrastructure. Some of the primary advantages of adopting a private cloud computing infrastructure were noted in a Forrester research on the benefits of supplying in-house cloud computing solutions for businesses:  Data security for customers. Despite public cloud companies' guarantees regarding security, few give adequate information or have long sufficient histories within their cloud products to issue guarantees regarding the exact degree of security implemented on their systems. It is easier to manage and rely on in-house security.  Infrastructure that ensures service level agreements (SLAs). Specific activities such proper clustering as well as failover, data replication, system monitoring and maintenance, disaster recovery, as well as other uptime services can be commensurate with the application demands, according to quality of service. Although some of these functionalities are provided by public cloud companies, some don't of them would be available when needed.  Adherence to established processes and operations. When delivering and running apps, companies must follow certain procedures if they are exposed to third-party compliance norms. In the case of virtual public infrastructure, this may not be practicable.  All of these factors make using cloud-based infrastructures within private spaces a viable alternative.  Private clouds can be built on more diverse hardware from an architecture standpoint: they often rely on the current IT infrastructure already installed on the private 46 CU IDOL SELF LEARNING MATERIAL (SLM)

premises. A datacenter, a cluster, a corporate desktop grid, or a mix of these might be used. Depending on the service provided to cloud customers, the physical layer is supplemented by infrastructure management software or even a PaaS solution. Private clouds can be implemented in a variety of ways. Figure 3.2 depicts the solutions in detail, as well as a references to the most widely used software for deploying private clouds. Virtual machine technologies like Xen, KVM, and VMware serve as the cloud's foundations at the bottom of the software stack. VMware vCloud, Eucalyptus, and OpenNebula are examples of virtual machine management technologies that may be used to govern virtual infrastructure and to provide an IaaS solution. Although VMware vCloud is indeed a proprietary solution, Eucalyptus works seamlessly with Amazon Web Services interfaces as well as supports a variety of virtual machine technologies including Xen, KVM, and VMware. OpenNebula, like Eucalyptus, is an open-source virtual infrastructure management system that supports KVM, Xen, and VMware and is built to easily connect third-party IaaS providers. Because of its modular architecture, it is possible to add new functionality to the program, such as the ability to reserve virtual machine instances using Haizea as a scheduler. OpenPEX and InterGrid are two solutions that depend on earlier virtual machine administrators and provide value. OpenPEX is a web-based system that allows virtual machine instances to be reserved and is designed to work with a variety of back ends (at the moment only the support for Xen is implemented). InterGrid adds value to OpenNebula and Amazon EC2 by allowing virtual machine instances to be reserved and managing multiadministrative domain clouds. PaaS solutions can add another layer to private clouds and provide a high-level service. DataSynapse, Zimory Pools, Elastra, and Aneka are some of the private cloud deployment alternatives available. DataSynapse is a software company that specializes in application virtualization. DataSynapse provides a flexible environment for establishing private clouds on top of datacenters by depending on VMware virtualization technologies. Elastra Cloud Server is a cloud-based platform that makes it simple to configure and deploy distributed application infrastructures. Zimory offers an integrated infrastructure layer which automates the utilization of resource pools depending on virtualization technologies such as Xen, KVM, and VMware. It enables the creation of an internal cloud made up of sparse private and public resources, as well as the migration of applications within the current infrastructure. Aneka is a software development platform for building 47 CU IDOL SELF LEARNING MATERIAL (SLM)

Figure 3.2 Private clouds hardware and software Stack cloud infrastructure on heterogeneous hardware such as datacenters, clusters, and desktop grids. It offers a pluggable service-oriented architecture aimed primarily at facilitating the execution of distributed applications using various programming models such as bag of tasks, MapReduce, and others. Private clouds will provide in-house cloud computing solutions, but they have a restricted ability to grow elastically on demand when compared to public clouds. 3.5HYBRID CLOUD Public clouds are vast software / hardware infrastructures with adequate capacity to fulfil various users' demands, but they are vulnerable to security risks and administrative errors. Although the option of totally depending on either a public virtual infrastructure was enticing for firms that have yet to incur IT capital expenditure and have only just begun to assess its IT needs (i.e., start-ups), the private cloud option typically triumphs due to existing IT infrastructure. When it's vital to maintain data processing within an organization's walls or to make use of existing hardware and software infrastructure, private clouds are the ideal choice. The inability to grow on demand and properly meet peak loads is one of the key downsides of private installations. In this instance, it's critical to take advantage of public cloud capabilities as needed. As a result, a hybrid solution might be an intriguing way to combine the finest 48 CU IDOL SELF LEARNING MATERIAL (SLM)

including its private as well as public worlds. As a result, hybrid clouds have developed and spread. Hybrid clouds enable businesses to take use of existing IT infrastructures, keep sensitive data on premises, and expand and shrink naturally by deploying external resources as well as releasing them when they're no longer needed. The public section of the cloud, which may be utilized to undertake activities with less rigorous limits yet is part of a system burden, is then the only place where security issues exist. A hybrid cloud is depicted in Figure 3.3 as follows: It's a heterogeneous distributed system created by combining extra resources or services from one or more public clouds with a private cloud. They're also known as heterogeneous clouds because of this. Dynamic provisioning is indeed a critical component in this situation, as seen in the diagram. Hybrid clouds solve scalability problems by combining internal and external resources to meet capacity demands. Such resources as well as services are leased for the duration of the project and then released. Cloudbursting is another name for this process. Although the term \"hybrid cloud\" is broad, it mostly refers to That though infrastructure instead of software applications. The notion of integrating paid software services with current applications deployed in private premises is already part of service-oriented computing. Dynamic provisioning describes the capacity to acquire virtual machines on demand in order to expand the capabilities of the resultant distributed system and subsequently release them in an IaaS scenario. The foundations for establishing and administering hybrid clouds include infrastructure management software and PaaS solutions. Dynamic provisioning, in particular, adds a more complex scheduling algorithm and rules for private clouds, with the purpose of optimizing the amount spent to rent public resources. OpenNebula, an infrastructure management platform, currently has the capacity to integrate resources from public clouds like Amazon EC2. The virtual machine retrieved from the public infrastructure is handled in the same way as all other virtual machine instances maintained locally in this situation. What's needed now is a sophisticated scheduling engine that can distinguish between these resources and make intelligent allocations based on the funding available to expand the existing infrastructure. Advanced schedulers, such as Haizea, can be incorporated with OpenNebula to enable cost-based scheduling. InterGrid has a different method. This really is basically a distributed scheduling engine for managing virtual machine allocation in a collection of peer networks. A local cluster, a gateway to a public cloud, or a mixture of the two can be used to depict such networks. When a request is sent to being one of the InterGrid gateways, it may be handled by assigning virtual instances across all peered networks, with the allocation of requests taking into consideration the user budget and network peering arrangements. PaaS systems that enable hybrid clouds are more likely to use dynamic provisioning. One of the most important aspects of PaaS middleware, as previously mentioned, seems to be the mapping of dispersed applications to cloud infrastructure. In this case, dynamic provisioning plays a critical role in ensuring that apps are executed according to the QoS that the user has 49 CU IDOL SELF LEARNING MATERIAL (SLM)

agreed to. Aneka, for example, offers a provisioning solution that uses several IaaS providers to scale current cloud infrastructure. The provisioning service collaborates with both the scheduler, that is in charge of ensuring that applications receive a certain QoS. Figure 3.3 Hybrid Cloud Each user program, in particular, has a budget, which the scheduler utilizes to optimize the program's execution via renting virtual nodes as needed. Other PaaS technologies allow for the development of hybrid clouds as well as dynamic provisioning. Elastra CloudServer but also Zimory Pools are two of the private cloud deployment and administration tools that have been considered. 3.6COMMUNITY CLOUD Community clouds were distributed systems that combine the services of several clouds to meet the demands of a particular industry, community, or business sector. Community clouds are defined as follows by the National Institute of Standards and Technologies (NIST): Several groups share the infrastructure, which serves a specific population with common issues (e.g., mission, security requirements, policy, and compliance considerations). It can be handled by the organizations themselves or by a third party, and it can be on-site or off-site. 50 CU IDOL SELF LEARNING MATERIAL (SLM)