2. CLOUD COMPUTING A.RAGAVENDRAN, S.SETHUPATHY Department of Computer science and engineering Nandha Engineering College email@example.com firstname.lastname@example.orgABSTRACT  Remotely hosted: Services or data are hosted on someone else’sCloud computing is one of the latest infrastructure.computer and business industry buzz  Ubiquitous: Services or data arewords. It joins the ranks of virtualization, available from anywhere.grid computing, and clustering, among  Co modified: The result is a utilityothers, in the IT industry. Cloud computing model similar to traditionalcomputing is a technology that uses the that of traditional utilities, like gasinternet and central remote servers to and electricity. You pay for what youmaintain data and applications. Cloud would like.computing allows consumers andbusinesses to use applications without INTRODUCTIONinstallation and access their personal files Cloud computing is one of the most talkedat any computer with internet access. This about topics in the industry today.Cloudtechnology allows for much more efficient computing is a concept where applicationscomputing by centralizing storage, and files are hosted on a “cloud”memory processing and bandwidth. This consisting of thousands of computers andpaper will discuss the definition of cloud servers, all linked together and accessiblecomputing, three categories of cloud via the Internet. With cloud computing,computing, needs of cloud computing. everything you do is now web basedCloud computing is an umbrella term used instead of being desktop based. You canto refer to Internet based development and access all your programs and documentsservices. The cloud is a metaphor for the from any computer that‟s connected to theInternet. A number of characteristics Internet. The user no longer needs todefine cloud data, applications services remember where the data is. All thatand infrastructure: matters is that the data is in the cloud, and thus immediately available to that user and to other authorized users.
3. DEFINITION OF CLOUD where an application is hosted as a serviceCOMPUTING: provided to customers across the Internet. SaaS is generally used to refer to businessCloud computing has become a scalable software rather than consumer software,service delivery platform in the field of which falls under Web 2.0. By removingservices computing. The technical the need to install and run an applicationfoundation of cloud computing include on a user‟s own computer it is seen as aService Oriented Architecture (SOA) The way for businesses to get the same benefitsgoal of cloud computing is to share as commercial software with smaller costresources among the cloud computing is to outlay. Saas also alleviates the burden ofshare resources among the cloud service software maintenance and support butconsumers, cloud partners and cloud users relinquish control over softwarevendors in the cloud value chain. A public versions and requirements. They othercloud sells services to anyone on the terms that are used in this sphere includeInternet. A private cloud is a data center Platform as a Service (PaaS) andthat supplies hosted services to a limited Infrastructure as a Service (IaaS).number of people. In the software-as-a-service cloud model, the vendor supplies the hardware infrastructure, the software product and interacts with the user through a front-end portal. SaaS is a very broad market. Services can be anything from Web-based email to inventory control and database processing. Because the service provider hosts both the application and the data, the end user is free to use the service fromTHREE CATEGORIES OF CLOUD anywhere.COMPUTING: Infrastructure-as-a-Service (IaaS):  Software-as-a-Service ( SaaS )  Infrastructure-as-a-Service (IaaS) Infrastructure-as-a-Service like Amazon  Platform-as-a-Service(PaaS) Web Services provides virtual serverSoftware as a Service (SaaS): instances with unique IP addresses andSaaS is a model of software deployment blocks of storage on demand. Customers
4. use the providers application program One of the premises of cloud computing isinterface (API) to start, stop, access and that services are delivered transparentlyconfigure their virtual servers and storage. regardless of the physical implementationIn the enterprise, cloud computing allows a within the "cloud". Transparency is one ofcompany to pay for only as much capacity the foundational concepts of cloudas is needed, and bring more online as computing, in that the actualsoon as required. Because this pay-for- implementations of services in the “cloud”what-you-use model resembles the way are obscured from the user. This is actuallyelectricity, fuel and water are consumed; another version of virtualization, whereits sometimes referred to as utility multiple resources appear to the user as acomputing. single resource.Look & Feel Cloud Architecture: Scalability:Cloud Computing - Cloud services and Obviously cloud computing servicestorage are accessible from anywhere in providers are going to need to scale up andthe world over an Internet connection. build out "mega data centers". Scalability is easy enough if youve deployed the proper application delivery solution, but what about scaling the application delivery solution? Thats often not so easy and it usually isnt a transparent process; theres configuration work and, in many cases, re- architecting of the network. The potential to interrupt services is huge, and assuming Fig.1: layout of common cloud that cloud computing service providers are servicing hundreds of thousands ofNEED FOR COMPUTING: customers, unacceptable.  Transparency Intelligent Monitoring:  Scalability  Intelligent Monitoring In order to achieve the on-demand  Security scalability and transparency required of a mega data center in the cloud, the controlTransparency: node, i.e. application delivery solution,
5. will need to have intelligent monitoring correct resources and then calls thecapabilities. It will need to understand system‟s appropriate provisioningwhen a particular server is overwhelmed services.and when network conditions are • These services includeadversely affecting application a. Shape out the necessaryperformance. It needs to know the resources in the cloudapplications and services being served b. Launch the appropriate webfrom the cloud and understand when applicationbehavior is outside accepted norms. c. Opens the requestedSecurity: document.Cloud computing is somewhat risky in that • Web application is launchedif the security of the cloud is compromised • System‟s monitoring functionspotentially all services and associated data track the usage of the cloud so thatwithin the cloud are at risk. That means resources are allocated andthat the mega data center must be attributed to the proper user(s).architected with security in mind, and it • User is charged according to themust be considered a priority for every amount of utilities and resourcesapplication, service, and network used.infrastructure solution that is deployed.The application delivery solution, as the"control node" in the mega data center, isnecessarily one of the first entry pointsinto the cloud data center and must itselfbe secure.CLOUD ARCHITECTURE: • Users select a task or service CLOUD STORAGE: (either starting an application or • With cloud storage, data is stored opening a document). on multiple third-party servers, • User‟s request goes to the system rather than on the dedicated management, which finds the servers.
6. • When storing data, the user sees a The front end includes the clients virtual server—that is, it appears computer (or computer network) and as if the data is stored in a the application required to access the particular place with a specific cloud computing system. Not all cloud name. computing systems have the same user• In reality, the user‟s data could be interface. Services like Web-based e- stored on any one or more of the mail programs leverage existing Web computers used to create the cloud. browsers like Internet Explorer or• Data stored in the cloud is secure Firefox. Other systems have unique from accidental erasure or applications that provide network hardware crashes, because it is access to clients. duplicated across multiple physical On the back end of the system are the machines. various computers, servers and data storage systems that create the "cloud"Several large Web companies (such as of computing services. In theory, aAmazon and Google) are now cloud computing system could includeexploiting the fact that they have data practically any computer program youstorage capacity which can be hired out can imagine, from data processing toto others. This approach, known as video games. Usually, each application„cloud storage‟ allows data stored will have its own dedicated server.remotely to be temporarily cached on A central server administers thedesktop computers, mobile phones or system, monitoring traffic and clientother Internet-linked devices. demands to ensure everything runsAmazon‟s Elastic Compute Cloud smoothly. It follows a set of rules 2(EC ) and Simple Storage Solution called protocols and uses a special(S3) are well known examples. kind of software called middleware.When talking about a cloud computing Middleware allows networkedsystem, its helpful to divide it into two computers to communicate with eachsections: the front end and the back other.end. They connect to each otherthrough a network, usually the Internet. A simple example of cloud computing isThe front end is the side the computer Yahoo email or Gmail etc. You dont needuser, or client, sees. The back end is a software or a server to use them. All athe "cloud" section of the system. consumer would need is just an internet
7. connection and you can start sending o Google (GOOG) - Appsemails. The server and email management Enginesoftware is all on the cloud (internet) and o Amazon.com (AMZN) -is totally managed by the cloud service EC2provider Yahoo, Google etc. The INFRASTRUCTURE:consumer gets to use the software aloneand enjoy the benefits. The final segment in cloud computing, known as the infrastructure, is very muchPLATFORMS: the backbone of the entire concept.Many of the companies that started out Infrastructure vendors environments (suchproviding on Demand application services as Google gears) that allow users to buildhave developed platform services as well. applications. Cloud storage, such asThe platform segment of cloud computing Amazons S3, is also considered to be partrefers to products that are used to deploy of the infrastructure segment.internet. NetSuite, Amazon, Google, and  Major Infrastructure Vendors -Microsoft have also developed platforms Below are companies that providethat allow users to access applications infrastructure services:from centralized servers. o Google (GOOG) - ManagedIn July 2008, HP, Yahoo! (YHOO), and hosting, developmentIntel (INTC) announced a joint cloud environmentcomputing research project called the o International BusinessCloud Computing Test Bed. The Machines (IBM) - Managedcompanies are jointly designing and hostingproducing the internet based testing CONCLUSION:utilizing HP hardware and Intel processors. The long dreamed vision of computing as  Active platforms - The following a utility is finally emerging. The elasticity companies are some that have of a utility matches the need of businesses developed platforms that allow end providing services directly to customers users to access applications from over the Internet. From the cloud centralized servers using the provider‟s view, the construction of large internet. Next to each company is datacenters at low cost uncovered the the name of their platform. possibility of selling resources on a pay-
8. as-you-go model below the costs of  Allows IT to shift focus - Nomedium-sized datacenters. From the cloud longer having to worry aboutuser‟s view, it would be as startling for a constant server updates and othernew software startup to build its own computing issues, governmentdatacenter. Also many other organizations organizations will be free totake advantage of the elasticity of cloud concentrate on innovation.computing such as newspapers likeWashington Post, movie companies like REFERENCES:Pixar.  W.-K. Chen, Linear Networks and Systems (Book style). Belmont,BENEFITS: CA: Wadsworth, 1993, pp. 123–135.  Reduced Cost - Cloud technology  B. Smith, “An approach to graphs of is paid incrementally, saving linear forms (Unpublished work organizations money. style),” unpublished.  Increased Storage - Organizations  M. Young, The Techincal Writers can store more data than on private Handbook. Mill Valley, CA: computer systems. University Science, 1989.  Highly Automated - No longer do  S. Chen, B. Mulgrew, and P. M. Grant, IT personnel need to worry about “A clustering technique for digital keeping software up to date. communications channel equalization  Flexibility - Cloud computing using radial basis function networks,” offers much more flexibility than IEEE Trans. Neural Networks, vol. 4, past computing methods. pp. 570–578, Jul. 1993.  More Mobility - Employees can  R. W. Lucky, “Automatic equalization access information wherever they for digital communication,” Bell Syst. are, rather than having to remain at Tech. J., vol. 44, no. 4, pp. 547–588, their desks. Apr. 1965.