Report_seminar.docx

VIRTUALISATION IN CLOUD COMPUTING Seminar report submitted for partial fulfilment of the requirement for the degree Of Bachelor of Technology By Megha Mishra Regd. No: 1501106377

Under the guidance of Mrs. Pranati Mishra

DEPARTMENT OF COMPUTER SCIENCE AND ENGINEERING COLLEGE OF ENGINEERING AND TECHNOLOGY BHUBANESWAR 2018-19 1

CERTIFICATE This is to certify that the report entitled “VIRTUALISATION IN CLOUD COMPUTING” is submitted by MEGHA MISHRA, bearing registration number 1501106377, to the Department of Computer Science and Engineering, College of Engineering and Technology, Bhubaneswar, is a record of bona fide work under our supervision and we consider it worthy of consideration for partial fulfilment of the requirement for the award of the degree of Bachelor of Technology in Computer Science and Engineering.

Date:

(Dr. Subashis Mohapatra) HOD, CSE CET, Bhubaneswar

(Mrs. Pranati Mishra) Seminar Guide CET, Bhubaneswar

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ACKNOWLEDGEMENT It is my privilege and solemn duty to express my deepest sense of gratitude to Mrs. Pranati Mishra, under whose able guidance I carried out this work, for her valuable suggestions, constant co-operation, timely aid and advice till the completion of the thesis. I would like to thank Dr. Subashish Mohapatra, Head of the Department for his encouragement and inspiration. I wish to offer my sincere gratitude to our respected Principal, Prof. (Dr.) P.K.Patra for his constant support and encouragement. I take this opportunity to express my heartfelt thanks to all those who helped me in my project work. I am extremely grateful to the authors of all the articles on the internet, for providing me with relevant information. I would like to thank my parents for their constant love and support. Last, but not the least, I would like to thank my classmates for their valuable comments and suggestions without which this report would not have seen the light of the day.

Megha Mishra Regd No: 1501106377

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CONTENTS 1.

Introduction

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2.

Cloud Computing Types of Cloud Services Types of Cloud Deployments

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Virtualisation in Cloud Computing Difference between Virtualisation and Cloud Computing What is Virtualisation? Virtualisation Architecture Hypervisor Types of Hypervisor Server with and without Virtualisation Need for virtualising servers Types of Virtualisation Hardware Virtualisation Network Virtualisation Storage Virtualisation Memory Virtualisation Software Virtualisation Data Virtualisation Desktop Virtualisation

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Green Computing Ways to promote Green Computing Approaches to make our computing greener How virtualisation aids in Green Computing

23 23 24 24

References

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2.1 2.2 3. 3.1 3.2 3.3 3.3.1 3.3.2 3.3.3 3.4 3.5 3.5.1 3.5.2 3.5.3 3.5.4 3.5.5 3.5.6 3.5.7 4. 4.1 4.2 4.3 5.

11 12 12 13 14 14 15 16 17 18 19 20 21 22

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ABSTRACT Cloud Computing is a novel buzzword in information technology domain. It's an emerging technology and it has been given much attention by both research community and industries. Cloud computing typically starts with virtualization. Virtualization is using computer resources to imitate other computer resources or whole computer. It separates resources and services from the underlying physical delivery environment. Virtualization can be applied to: memory, network, storage, hardware, operating system, applications. It is important for cloud computing because it decouples the software from the hardware. In this seminar we will be focusing on the situation before virtualization, necessity of virtualization, its types, advantages and how it aids in Green Computing. Virtualization helps to reduce energy costs and thereby, is the most sought-after technology in the IT world which facilitates Cloud Computing.

KEYWORDS Cloud Computing; Virtualization; Hypervisor; Green Computing.

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INTRODUCTION Whether we are running applications that share photos to millions of mobile users or we’re supporting the critical operations of your business, a cloud services platform provides rapid access to flexible and low-cost IT resources. With cloud computing, we don’t need to make large upfront investments in hardware and spend a lot of time on the heavy lifting of managing that hardware. Instead, we can provision exactly the right type and size of computing resources we need to power our newest bright idea or operate our IT department. We can access as many resources as we need, almost instantly, and only pay for what you use. And this is powered by ‘virtualisation’, the foundational element of cloud computing.

CLOUD COMPUTING Cloud computing is the use of various services, such as software development platforms, servers, storage and software, over the internet, often referred to as the "cloud." It is an information technology (IT) paradigm that enables ubiquitous access to shared pools of configurable system resources and higher-level services that can be rapidly provisioned with minimal management effort, often over the Internet. Cloud computing relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility. Third-party clouds enable organizations to focus on their core businesses instead of expending resources on computer infrastructure and maintenance. Advocates note that cloud computing allows companies to avoid or minimize up-front IT infrastructure costs. Proponents also claim that cloud computing allows enterprises to get their applications up and running faster, with improved manageability and less maintenance, and that it enables IT teams to more rapidly adjust resources to meet fluctuating and unpredictable demand. Cloud providers typically use a "pay-as-you-go" model, which can lead to unexpected operating expenses if administrators are not familiarized with cloud-pricing models. [1]

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TYPES OF CLOUD SERVICES Most cloud computing services fall into three broad categories: infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS). These are sometimes called the cloud computing stack, because they build on top of one another. 

Infrastructure-as-a-service (IaaS)

The most basic category of cloud computing services. With IaaS, you rent IT systems, servers and virtual machines (VMs), storage, networks, operating systems—from a cloud provider on a pay-as-you-go basis. Examples are: Amazon Web Services (AWS), Cisco Metapod, Microsoft Azure, Google Compute Engine (GCE).

Fig. IaaS

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Platform as a service (PaaS)

Platform-as-a-service (PaaS) refers to cloud computing services that supply an on-demand environment for developing, testing, delivering and managing software applications. PaaS is designed to make it easier for developers to quickly create web or mobile apps, without worrying about setting up or managing the underlying infrastructure of servers, storage, network and databases. Examples are: Windows Azure, Heroku, Force.com, GAE.

Fig. PaaS

 Software as a service (SaaS) Software-as-a-service (SaaS) is a method for delivering software applications over the Internet, on demand and typically on a subscription basis. With SaaS, cloud providers host and manage the software application and underlying infrastructure and handle any maintenance, like software upgrades and security patching. Users connect to it over the Internet, usually with a web browser on their phone, tablet or PC. Examples are: Google Apps, Dropbox. [2]

Fig. SaaS 7

TYPES OF CLOUD DEPLOYMENTS Not all clouds are the same. There are three different ways to deploy cloud computing resources: public cloud, private cloud and hybrid cloud.

 Public cloud Public clouds are owned and operated by a third-party cloud service provider, which deliver their computing resources like servers and storage over the Internet. Microsoft Azure is an example of a public cloud. With a public cloud, all hardware, software and other supporting infrastructure is owned and managed by the cloud provider. You access these services and manage your account using a web browser.

 Private cloud A private cloud refers to cloud computing resources used exclusively by a single business or organisation. A private cloud can be physically located on the company’s on-site data center. Some companies also pay third-party service providers to host their private cloud. A private cloud is one in which the services and infrastructure are maintained on a private network.

Fig. Types of Cloud Deployments

 Hybrid cloud Hybrid clouds combine public and private clouds, bound together by technology that allows data and applications to be shared between them. By allowing data and applications to move between private and public clouds, hybrid cloud gives businesses greater flexibility and more deployment options. [2]

 Community cloud In the community cloud deployment model, the cloud infrastructure is shared by several organizations with the same policy and compliance considerations. This helps to further reduce costs as compared to a private cloud, as it is shared by larger group. [3]

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VIRTUALISATION IN CLOUD COMPUTING Virtualization is a technique how to separate a service from the underlying physical delivery of that service. It is the process of creating a virtual version of something like computer hardware. It was initially developed during the mainframe era. It involves using specialized software to create a virtual or software-created version of a computing resource rather than the actual version of the same resource. With the help of Virtualization multiple operating systems and applications can run on same Machine and its same hardware at the same time increasing the utilization and flexibility of hardware.

In other words, one of the main cost effective, hardware reducing, energy saving techniques used by cloud providers is virtualization. Virtualization is a technique, which allows to share a single physical instance of a resource or an application among multiple customers and organizations at one time. It does by assigning a logical name to a physical storage and providing a pointer to that physical resource on demand. The term virtualization is often synonymous with hardware virtualization, which plays a fundamental role in efficiently delivering Infrastructure-as-a-Service (IaaS) solutions for cloud computing. Moreover, virtualization technologies provide a virtual environment for not only executing applications but also for storage, memory, and networking. [4]

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DIFFERENCE BETWEEN VIRTUALISATION AND CLOUD COMPUTING At first glance, virtualization and cloud computing may sound like similar things, but each one has a broader definition that can be applied to many different kinds of systems. Both virtualization and cloud computing are often virtual in the sense that they rely on similar models and principles. However, cloud computing and virtualization are inherently different. Virtualization is a foundational element of cloud computing and helps deliver on the value of cloud computing. Virtualization is a software that manipulates hardware, while cloud computing refers to a service that results from that manipulation. The picture refers to the ‘Keystone-Arch’ structure. The keystone (virtualization) is the "key" to supporting the arch (cloud computing), because if you remove the stone, the arch would collapse. Similarly, we cannot have cloud computing without virtualisation. [5]

Fig. Keystone-Arch Structure

Virtualization is simply the replacement of some physical component with a virtual one. Within this broad definition, there are specific types of virtualization, such as virtual storage devices, virtual machines, virtual operating systems and virtual network components for network virtualization. Virtualization just means that someone built a model for something, such as a machine or server, into code, creating a software program function that acts like what it’s modelling. For instance, a virtual server sends and receives signals just like a physical one, even though it doesn’t have its own circuitry and other physical components. Cloud computing, on the other hand, is a specific kind of IT setup that involves multiple computers or hardware pieces sending data through a wireless or IP-connected network. In most cases, cloud computing environments involve sending inputted data to remote locations through a somewhat abstract network trajectory known as "the cloud." [6] 10

WHAT IS VIRTUALISATION? Virtualization is the ability to run multiple operating systems on a single physical system and share the underlying hardware resources. It is the creation of a virtual version of hardware using software. It allows us to run several applications at the same time on a single physical server by hosting each of them inside their own virtual machine. By running multiple virtual machines simultaneously, a physical server can be utilized efficiently.

Fig. Virtualisation

Virtualization refers to the creation of a virtual resource such as a server, desktop, operating system, file, storage or network. The main goal of virtualization is to manage workloads by radically transforming traditional computing to make it more scalable. Virtualization has been a part of the IT landscape for decades now, and today it can be applied to a wide range of system layers, including operating system-level virtualization, hardware-level virtualization and server virtualization. Virtualisation often includes computer-generated versions of hardware, operating systems, storage devices and more. This allows organisations to partition a single physical computer or server into several virtual machines. By creating multiple resources from a single computer or server, virtualisation improves scalability and workloads while resulting in the use of fewer overall servers, less energy consumption and less infrastructure costs and maintenance. There are four main categories virtualisation falls into. The first is desktop virtualisation, which allows one centralised server to deliver and manage individualised desktops. The second is network virtualisation, designed to split network bandwidth into independent channels to then be assigned to specific servers or devices. The third category is software virtualisation, which separates applications from the hardware and operating system. And the fourth is storage virtualisation, which combine multiple network storage resources into a single storage device where multiple users may access it. [7] 11

VIRTUALISATION ARCHITECTURE A virtualization architecture is a conceptual model specifying the arrangement and interrelationships of the particular components involved in delivering a virtual, rather than physical version of something, such as an operating system (OS), a server, a storage device or network resources. Virtualization is commonly hypervisor-based. The hypervisor isolates operating systems and applications from the underlying computer hardware so the host machine can run multiple virtual machines (VM) as guests that share the system's physical compute resources, such as processor cycles, memory space, network bandwidth and so on. [8]

Fig. Comparison between Traditional and Virtualised Server architecture

HYPERVISOR Hypervisor is a process that separates a computer’s operating system and applications from the underlying physical hardware. Usually done as software although embedded hypervisors can be created for things like mobile devices. The hypervisor drives the concept of virtualization by allowing the physical host machine to operate multiple virtual machines as guests to help maximize the effective use of computing resources such as memory, network bandwidth and CPU cycles. Hypervisor plays an important role in the virtualization scenario. A hypervisor is also known as a virtual machine manager (VMM). A hypervisor is a hardware virtualization technique that allows multiple guest operating systems (OS) to run on a single host system at the same time. The guest OS shares the hardware of the host computer, such that each OS appears to have its own processor, memory and other hardware resources. Hypervisors make it possible to use more of a system’s available resources, and provide greater IT mobility, since the guest VMs are independent of the host hardware. This means they can be easily moved between different servers. Examples: VMware, Xen, KVM (Kernel-based VM). [9] 12

TYPES OF HYPERVISOR 

TYPE-1 HYPERVISOR Type 1 hypervisors are deployed directly atop the system's hardware without any underlying operating systems or other software. These are called "bare metal" hypervisors and are the most common and popular type of hypervisor for the enterprise data center. They support hardware virtualization. Type 1 hypervisors are gaining popularity because building the hypervisor into the firmware is proving to be more efficient due to low overhead. They provide higher performance, availability, and security than Type 2 hypervisors. Examples of Type 1 hypervisors include vSphere or Hyper-V.

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TYPE-2 HYPERVISOR Type 2 hypervisors run as a software layer atop a host operating system and are usually called "hosted" hypervisors like VMware Player or Parallels Desktop. Hosted hypervisors are often found on endpoints like PCs. Type 2 hypervisors run on a host operating system. It operates as an application on top of an existing operating system, therefore supports software virtualization. They are used mainly on client systems where efficiency is less critical or on systems where support for a broad range of I/O devices is important. Example of Type 2 hypervisors include Linux KVM, Oracle Virtual Box. [10]

Fig. Types of Hypervisor 13

SERVER WITHOUT VIRTUALISATION     

Only one OS can run at a time within a server. Underutilization of resources takes place. Inflexible and costly infrastructure. Software and hardware tightly coupled. Hardware changes require manual effort and access to the physical server. Fig. Server without virtualization

SERVER WITH VIRTUALISATION     

Can run multiple OS simultaneously. Each OS can have a different hardware configuration. Efficient utilization of hardware resources. Each virtual machine is independent. Easy to manage and monitor virtual machines centrally.

Fig. Server with virtualization

NEED FOR VIRTUALISING SERVERS 1. Reduced total cost of ownership In a virtualised (IaaS) environment you are no longer paying for hardware upfront so your capital expenditure costs are immediately reduced. Additionally, when you virtualise you reduce power draw and cooling requirements in your datacentre. In short, you need fewer resources to run your servers and this means lower costs. 2. Flexibility Virtual environments give you the capability to run multiple operating systems on the same hardware which means you can extend the life of legacy applications without maintaining ageing hardware. 14

3. Continuity So long as you have the right backup hardware technology you can recover from a disaster in a fraction of the time thanks to Virtual Machine snapshots. If an instance fails you simply kill it and load the latest “safe” snapshot. Automation options are available and there are advanced options that allow you to redeploy a server on another host machine without sacrificing downtime. Development and test environments can be cloned identically from live environments at the push of a button, allowing you to test without buying extra hardware or interfering with production. 4. Scaling Virtualisation makes it quick and easy to scale your resources up or down. For example, you can increase the processing power and memory available to an individual server simply by allocating more resources to it. There's no need to physically add extra RAM or CPU components, as you would with a physical server. This means your business can respond in real time to operational needs and if your Cloud infrastructure is capable of “spawning new instances” to cope with demand then you only pay for the processing power and bandwidth that you actually need. 5. Automation Provisioning a new server, automating failover and scaling resources is very simple when you use the latest virtualisation control panels. The majority of maintenance tasks can be managed through the console and set up to run by themselves, across any number of instances. [11]

TYPES OF VIRTUALIZATION Virtualization is of 7 types: 1. Hardware Virtualization 2. Network Virtualization 3. Storage Virtualization 4. Memory Virtualization 5. Software Virtualization 6. Data Virtualization 7. Desktop Virtualization Fig. Types of Virtualisation

The various types are described below in brief with appropriate diagrams. [12]

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1. HARDWARE VIRTUALIZATION It is the most common type of virtualization and it provides advantages like optimum hardware utilization and application uptime. The basic idea is to combine many small physical servers into one large physical server, so that the processor can be used more effectively. The operating system that is running on a physical server gets converted into a well-defined OS that runs on the virtual machine. Hardware virtualization is further subdivided into the following types: 

Paravirtualization is virtualization in which the guest operating system (the one being virtualized) is aware that it is a guest and accordingly has drivers that, instead of issuing hardware commands, simply issue commands directly to the host operating system.

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Full Virtualization is virtualization in which the guest operating system is unaware that it is in a virtualized environment, and therefore hardware is virtualized by the host operating system so that the guest can issue commands to what it thinks is actual hardware, but really are just simulated hardware devices created by the host.

Fig. Types of Hardware Virtualization

Hardware virtualization installs a hypervisor or virtual machine manager (VMM), which creates an abstraction layer between the software and the underlying hardware. Once a hypervisor is in place, software relies on virtual representations of the computing components, such as virtual processors rather than physical processors. Popular hypervisors include VMware's vSphere, based on ESXi, and Microsoft's Hyper-V. Virtualized computing resources are provisioned into isolated instances called VMs, where OSes and applications can be installed. Virtualized systems can host multiple VMs simultaneously, but every VM is logically isolated from every other VM. This means a malware attack or a crash of one VM won't affect the other VMs. Support for multiple VMs vastly increases the system's utilization and efficiency. [13]

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2. NETWORK VIRTUALIZATION Network virtualization (NV) is using network resources through a logical segmentation of a single physical network. It also automates many network administrative tasks. Network virtualization is specifically useful for networks that experience a huge, rapid, and unpredictable traffic increase. The intended result of network virtualization provides improved network productivity and efficiency. Two categories of Network Virtualization: 1. Internal: Provide network like functionality to a single system. 2. External: Combine many networks, or parts of networks into a virtual unit.

Fig. Network Virtualisation

When applied to a network, virtualization creates a logical software-based view of the hardware and software networking resources (switches, routers, etc.). The physical networking devices are simply responsible for the forwarding of packets, while the virtual network (software) provides an intelligent abstraction that makes it easy to deploy and manage network services and underlying network resources. As a result, NV can align the network to better support virtualized environments. ADVANTAGES OF NETWORK VIRTUALISATION 

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NV can be used to create virtual networks within a virtualized infrastructure. This enables NV to support the complex requirements in multi-tenancy environments. NV can deliver a virtual network within a virtual environment that is truly separate from other network resources. [14] With virtualization, companies can take advantage of the efficiencies and agility of software-based compute and storage resources. The true decoupling of the control and forwarding planes, as advocated by software-defined networking (SDN) and network functions virtualization (NFV), that network virtualization has become more of a focus. 17

3. STORAGE VIRTUALIZATION Storage virtualization or cloud storage is the process of grouping the physical storage from multiple network storage devices into a single storage device. This virtualization concept addresses the complexity of data and storage management allowing easy backup, archiving and task recovery in a less time.

Fig. Storage Virtualization

The virtual storage software intercepts I/O requests from physical or virtual machines and sends those requests to the appropriate physical location of the storage devices that are part of the overall pool of storage in the virtualized environment. To the user, virtual storage appears like a standard read or write to a physical drive. Even a RAID array can sometimes be considered a type of storage virtualization. Multiple physical disks in the array are presented to the user as a single storage device that, in the background, replicates data to multiple disks in case of a single disk failure. There are two basic methods of virtualizing storage: file-based and block-based. 

File-based storage virtualization is a specific use case, applied to network-attached storage (NAS) systems.

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Block-based systems abstract the logical storage, from the actual physical memory blocks in a storage device, such as a hard disk drive or solid-state memory device.

ADVANTAGES OF STORAGE VIRTUALIZATION:     

It provides improved storage management in a heterogeneous IT environment. SV facilitates easy updates and better availability. Reduced downtime makes storage virtualization comparatively efficient. Better storage utilization takes place. Automated management interface makes it easier for us to maintain the software. 18

4. MEMORY VIRTUALIZATION It introduces a way to decouple memory from the server to provide a shared, distributed or networked function. It enhances performance by providing greater memory capacity without any addition to the main memory. That’s why a portion of the disk drive serves as an extension of the main memory. Implementations: 1. Application-level integration – Applications running on connected computers directly connect to the memory pool through an API or the file system. 2. Operating System Level Integration – The operating system first connects to the memory pool, and makes that pooled memory available to applications.

Fig. Application-level integration

Fig. Operating system-level integration

ADVANTAGES OF MEMORY VIRTUALISATON 

Extending memory beyond a physical server’s capacity.

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Implementing shared memory for clustered or grid computing environments.

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Enabling Cloud Computing and Real-Time Infrastructure in the enterprise data center.

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Fewer servers, one mainframe to run multiple apps, higher capacity networked storage, resulting in tremendous cost savings. 19

5. SOFTWARE VIRTUALIZATION It provides the ability to the main computer to run and create one or more virtual environments. It is used to enable a complete computer system in order to allow a guest OS to run. For instance, letting Linux to run as a guest that is natively running a Microsoft Windows OS (or vice versa, running Windows as a guest on Linux). Types of Software Virtualization: 1. Operating system virtualization: Operating system virtualization (OS virtualization) is a server virtualization technology that involves tailoring a standard operating system so that it can run different applications handled by multiple users on a single computer at a time. The operating systems do not interfere with each other even though they are on the same computer. Some tools are VirtualBox and VMLite Workstation. 2. Application virtualization: Application virtualization is software technology that encapsulates computer programs from the underlying operating system on which it is executed. A fully virtualized application is not installed in the traditional sense, although it is still executed as if it were. The application behaves at runtime like it is directly interfacing with the original operating system and all the resources managed by it, but can be isolated or sandboxed to varying degrees. Some tools are Parallels Remote Application Server (RAS) and XenApp. 3. Service virtualization: Service virtualization is a simulation software. It allows organizations to execute tests even when the Application/Microservice does not exist. It supports developers and testing teams to get access dependent system components. Some service virtualisation tools are Traffic Parrot and Mountebank. [15]

Fig. OS, Service and Application Virtualisation 20

6. DATA VIRTUALIZATION It is an approach to data management that allows an application to retrieve and manipulate data without requiring technical details about the data, such as how it is formatted or where it is physically located. Without any technical details, you can easily manipulate data and know how it is formatted or where it is physically located. It decreases the data errors and workload. Data virtualization is synonymous with information agility - it delivers a simplified, unified, and integrated view of trusted business data in real time or near real time as needed by the consuming applications, processes, analytics, or business users. Data virtualization integrates data from disparate sources, locations and formats, without replicating the data, to create a single "virtual" data layer that delivers unified data services to support multiple applications and users. The result is faster access to all data, less replication and cost, more agility to change.

ADVANTAGES OF DATA VIRTUALISATION 

Data virtualization is modern data integration: It performs Extract-Transform-Load (ETL), data replication, data federation, Enterprise Service Bus (ESB), etc. but leveraging modern technology to deliver real-time data integration at lower cost, with more speed and agility. It can replace traditional data integration and reduce the need for replicated data marts and data warehouses in many cases.

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Data virtualization is also an abstraction layer and a data services layer: In this sense it is highly complementary to use between original and derived data sources, ETL, ESB and other middleware, applications, and devices, whether on-premise or cloudbased, to provide flexibility between layers of information and business technology. [16] 21

7. DESKTOP VIRTUALIZATION

Desktop virtualization is the concept of isolating a logical operating system (OS) instance from the client that is used to access it. Desktop virtualization is a virtualization technology that separates an individual's PC applications from his or her desktop. Virtualized desktops are generally hosted on a remote central server, rather than the hard drive of the personal computer. Because the client-server computing model is used in virtualizing desktops, desktop virtualization is also known as client virtualization.

Fig. Desktop Virtualisation

Desktop virtualization "virtualizes desktop computers" and these virtual desktop environments are "served" to users on the network. You interact with a virtual desktop in the same way you would use a physical desktop. Another benefit of desktop virtualization is that is lets you remotely log in to access your desktop from any location. VDI (Virtual Desktop Infrastructure -- or Interface) is a popular method of desktop virtualization. This type of desktop virtualization uses the server computing model, as the desktop virtualization in this scenario is enabled through hardware and software. VDI hosts the desktop environment in a virtual machine (VM) that runs on a centralized or remote server. ADVANTAGES OF DESKTOP VIRTUALIZATION     

It provides the work convenience and security. As one can access remotely, you are able to work from any location and on any PC. It provides a lot of flexibility for employees to work from home or on the go. It also protects confidential data from being lost or stolen by keeping it safe on central servers. From an IT perspective, virtual desktops help reduce the time it takes to provision new desktops, and they also help to decrease desktop management and support costs. 22

GREEN COMPUTING

Green computing is the environmentally responsible and eco-friendly use of computers and their resources. In broader terms, it is also defined as the study of designing, manufacturing/engineering, using and disposing of computing devices in a way that reduces their environmental impact. It is the environmentally responsible and eco-friendly use of computers and their resources. In broader terms, it is also defined as the study of designing, engineering, manufacturing, using and disposing of computing devices in a way that reduces their environmental impact. Many IT manufacturers and vendors are continuously investing in designing energy-efficient computing devices, reducing the use of dangerous materials and encouraging the recyclability of digital devices. Green computing practices came into prominence in 1992, when the Environmental Protection Agency (EPA) launched the Energy Star program. Green computing is also known as green information technology (green IT). Green computing aims to attain economic viability and improve the way computing devices are used. Green IT practices include the development of environmentally sustainable production practices, energy-efficient computers and improved disposal and recycling procedures. [17]

APPROACHES TO PROMOTE GREEN COMPUTING To promote green computing concepts at all possible levels, the following four approaches are employed:    

Green use: Minimizing the electricity consumption of computers and their peripheral devices and using them in an eco-friendly manner. Green disposal: Repurposing existing equipment or appropriately disposing of, or recycling, unwanted electronic equipment. Green design: Designing energy-efficient computers, servers, printers, projectors and other digital devices. Green manufacturing: Minimizing waste during the manufacturing of computers and other subsystems to reduce the environmental impact of these activities. [18]

Government regulatory authorities also actively work to promote green computing concepts by introducing several voluntary programs and regulations for their enforcement.

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WAYS TO MAKE OUR COMPUTING USAGE GREENER Average computer users can employ the following tactics to make their computing usage greener: [19]       

Use the hibernate or sleep mode when away from a computer for extended periods. Buy energy-efficient notebook computers, instead of desktop computers. Activate the power management features for controlling energy consumption. Make proper arrangements for safe electronic waste disposal. Turn off computers at the end of each day. Refill printer cartridges, rather than buying new ones. Instead of purchasing a new computer, try refurbishing an existing device.

HOW VIRTUALIZATION AIDS IN GREEN COMPUTING 1. Decreased Energy Use: Virtualization is more environment-friendly. It means a big reduction in power consumption. Reducing the number of physical devices, the amount of energy required to operate the devices is decreased. Also, the amount of energy required to cool the environment and the system is reduced.

2. Reduction in Facility Requirements: Virtualization leads to a dramatic reduction in physical equipment which will help us ‘go green’. If the amount of equipment is reduced, so are space requirements, which means business can increase without having to build ever larger data centres.

3. Reduction of Toxic Wastes: Along with a reduction in your electric bill, virtualized servers result in a reduction of your data center footprint, and on an enterprise level, your carbon footprint. That also translates to lower overall costs as well. Since the number hardware devices are decreased, there is a huge decrease in e-waste and hence reduction in toxic wastes. [20] 24

REFERENCES [1] https://en.wikipedia.org/wiki/Cloud_computing [2] https://azure.microsoft.com/en-in/overview/what-is-cloud-computing/ [3] https://cloudtweaks.com/2012/07/4-primary-cloud-deployment-models/ [4] https://www.geeksforgeeks.org/virtualization-cloud-computing-types/ [5] https://beacontelecom.com/virtualization-keystone-of-the-cloud-based-mindset/ [6] https://www.techopedia.com/7/29674/networking/what-is-the-difference-between-cloudcomputing-and-virtualization [7] https://www.vmware.com/pdf/virtualization.pdf [8] https://whatis.techtarget.com/definition/virtualization-architecture [9] https://www.networkworld.com/article/3243262/virtualization/what-is-a-hypervisor.html [10] https://searchservervirtualization.techtarget.com/definition/hypervisor [11] http://www.brainworx.co.nz/virtualising-server-right-can-help-find/ [12] https://www.znetlive.com/blog/virtualization-in-cloud-computing/ [13] https://searchservervirtualization.techtarget.com/definition/hardware-virtualization [14] https://www.sdxcentral.com/sdn/network-virtualization/definitions/whats-networkvirtualization/ [15] https://www.sdxcentral.com/sdn/network-virtualization/definitions/whats-networkvirtualization/ https://www.guru99.com/service-virtualization-tools.html [16] https://www.denodo.com/en/data-virtualization/overview [17] https://www.techopedia.com/definition/14753/green-computing [18] https://www.coursehero.com/file/p44hue7/To-promote-green-computing-concepts-at-allpossible-levels-the-following-four/ [19] https://data.conferenceworld.in/GKU/90.pdf [20] https://www.slideshare.net/RAHULSINHA1993/virtualization-in-green-computing

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