Cloud Computing Technology Essay

INTRODUCTION Cloud computing is Internet (â€Å"cloud†) based on development and use of computer technology (â€Å"computing†).It is a style of computing in which dynamically scalable and often virtualised resources are provided as a service over the internet.Users need not have knowledge of, expertise in, or control over the technology infrastructure â€Å"in the cloud† that supports them. The concept incorporates infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS) as well as Web 2.0 and other recent (ca. 2007-2009) technology trends which have the common theme of reliance on the Internet for satisfying the computing needs of the users. Examples of SaaS vendors include Salesforce.com and Google Apps which provide common business applications online that are accessed from a web browser, while the software and data are stored on the servers. A cloud is a pool of virtualized computer resources. A cloud can: 1.Host a variety of different workloads, including batch-style back-end jobs and interactive, user- facing applications. 2.Allow workloads to be deployed and scaled-out quickly through the rapid provisioning of virtual machines or physical machines. 3.Support redundant, self-recovering,highly scalable programming models that allow workloads to recover from many unavoidable hardware/software failures. 4.Monitor resource use in real time to enable rebalancing of allocations when needed. Fig 1.1: Overview of cloud computing HISTORY The underlying concept dates back to 1960 when John McCarthy opined that â€Å"computation may someday be organized as a public utility†; indeed it shares characteristics with service bureaus which date back to the 1960s.The term cloud had already come into commercial use in the early 1990s to refer to large ATM networks.By the turn of the 21st century,the term â€Å"cloud computing† had started to appear, although most of the focus at this time was on Software as a service (SaaS). In 1999, Salesforce.com was established by Marc Benioff, Parker Harris,and his fellows.They applied many technologies of consumer web sites like Google and Yahoo! to business applications. IBM extended these concepts in 2001,as detailed in the Autonomic Computing Manifesto-which described advanced automation techniques such as self-monitoring, self-healing, self-configuring, and self-optimizing in the management of complex IT systems with heterogeneous storage, servers, applications, networks, security mechanisms, and other system elements that can be virtualized across an enterprise. Amazon.com played a key role in the development of cloud computing by modernizing their data centres after the dot-com bubble and, having found that the new cloud architecture resulted in significant internal efficiency improvements,providing access to their systems by way of Amazon Web Services in 2002 on a utility computing basis. 2007 saw increased activity,with Google,IBM and a number of universities embarking on a large scale cloud computing research project, around the time the term started gaining popularity in the mainstream press. WORKING OF CLOUD COMPUTING Fig 1.2: Working of cloud computing In cloud computing you only need to load one application.This application would allow workers to log into a Web-based service which hosts all the programs the user would need for his or her job. Remote machines owned by another company would run everything from e-mail to word processing to complex data analysis programs.It’s called cloud computing, and it could change the entire computer industry. In a cloud computing system, there’s a significant workload shift.Local computers no longer have to do all the heavy lifting when it comes to running applications.The network of computers that make up the cloud handles them instead. Hardware and software demands on the user’s side decrease.The only thing the user’s computer needs to be able to run is the cloud computing system’s interface software, which can be as simple as a Web browser, and the cloud’s network takes care of the rest. CLOUD ARCHITECTURE Cloud architecture,the systems architecture of the software systems involved in the delivery of cloud computing, comprises hardware and software designed by a cloud architect who typically works for a cloud integrator. It typically involves multiple cloud components communicating with each other over application programming interfaces, usually web services. Cloud architecture extends to the client, where web browsers and/or software applications access cloud applications. Cloud storage architecture is loosely coupled, where metadata operations are centralized enabling the data nodes to scale into the hundreds, each independently delivering data to applications or users. Fig 1.3: Cloud architecture COMPONENTS 1. APPLICATION A cloud application leverages the Cloud in software architecture,often eliminating the need to install and run the application on the customer’s own computer,thus alleviating the burden of software maintenance, ongoing operation, and support. 2. CLOUD CLIENTS A cloud client consists of computer hardware and/or computer software which relies on the cloud for application delivery, or which is specifically designed for delivery of cloud services and which, in either case, is essentially useless without it. For example:Mobile ,Thin client ,Thick client / Web browser . 3. CLOUD INFRASTRUCTURE Cloud infrastructure,such as Infrastructure as a service,is the delivery of computer infrastructure, typically a platform virtualization environment,as a service.For example:grid computing ,Management , Compute ,Platform. 4. CLOUD PLATFORMS A cloud platform,such as Paas, the delivery of a computing platform,and/or solution saas,facilitates deployment of applications without the cost and complexity of buying and managing the underlying hardware and software layers. 5. CLOUD SERVICES A cloud service includes â€Å"products, services and solutions that are delivered and consumed in real-time over the Internet†.For example Web Services (â€Å"software system[s] designed to support interoperable machine-to-machine interaction over a network†) which may be accessed by other cloud computing components, software, e.g., Software plus services, or end users directly. 6. CLOUD STORAGE Cloud storage involves the delivery of data storage as a service, including database-like services, often billed on a utility computing basis, e.g., per gigabyte per month. For example Database ,Network attached storage ,Web service . TYPES OF CLOUDS 1. PUBLIC CLOUD Public cloud or external cloud describes cloud computing in the traditional mainstream sense, whereby resources are dynamically provisioned on a fine-grained, self-service basis over the Internet, via web applications/web services, from an off-site third-party provider who shares resources and bills on a fine-grained utility computing basis. 2. HYBRID CLOUD A hybrid cloud environment consisting of multiple internal and/or external providers â€Å"will be typical for most enterprises†. 3. PRIVATE CLOUD Private cloud and internal cloud are neologisms that some vendors have recently used to describe offerings that emulate cloud computing on private networks.These (typically virtualisation automation) products claim to â€Å"deliver some benefits of cloud computing without the pitfalls†, capitalising on data security, corporate governance, and reliability concerns. They have been criticised on the basis that users â€Å"still have to buy, build, and manage them† and as such do not benefit from lower up-front capital costs and less hands-on management ,essentially â€Å"[lacking] the economic model that makes cloud computing such an intriguing concept†.While an analyst predicted in 2008 that private cloud networks would be the future of corporate IT, there is some contention as to whether they are a reality even within the same firm. ROLES PLAYED IN CLOUD COMPUTING 1. CLOUD COMPUTING PROVIDERS A cloud computing provider or cloud computing service provider owns and operates live cloud computing systems to deliver service to third parties.Usually this requires significant resources and expertise in building and managing next-generation data centers.Some organisations realise a subset of the benefits of cloud computing by becoming â€Å"internal† cloud providers and servicing themselves, although they do not benefit from the same economies of scale and still have to engineer for peak loads. The barrier to entry is also significantly higher with capital expenditure required and billing and management creates some overhead.Nonetheless, significant operational efficiency and agility advantages can be realised, even by small organisations, and server consolidation and virtualization rollouts are already well underway.Amazon.com was the first such provider,modernising its data centers which,like most computer networks, were using as little as 10% of its capacity at any one time just to leave room for occasional spikes. This allowed small, fast-moving groups to add new features faster and easier, and they went on to open it up to outsiders as Amazon Web Services in 2002 on a utility computing basis. Players in the cloud computing service provision game include the likes of Amazon, Google, Hewlett Packard, IBM, Intel, Microsoft, Salesforce, SAP and Yahoo! 2. USER A user is a consumer of cloud computing.The privacy of users in cloud computing has become of increasing concern.The rights of users are also an issue, which is being addressed via a community effort to create a bill of rights. 3. VENDOR A vendor sells products and services that facilitate the delivery, adoption and use of cloud computing.For example:Computer hardware,Storage,infrastructure,Computer software,Operating systems ,Platform virtualization. APPLICATIONS OF CLOUD COMPUTING 1.EASY ACCESS TO DATA Clients would be able to access their applications and data from anywhere at any time.They could access the cloud computing system using any computer linked to the internet. 2. REDUCTION OF COSTS It could bring hardware costs down.Cloud computing systems would reduce the need for advanced hardware on the client side.You wouldn’t need to buy the fastest computer with the most memory, because the cloud system would take care of those needs for you. Instead, you could buy an inexpensive computer terminal, enough processing power to run the middleware necessary to connect to the cloud system. 3. CONVENIENCE Corporations that rely on computers have to make sure they have the right software in place to achieve goals. Cloud computing systems give these organizations company-wide access to computer applications.Instead, the company could pay a metered fee to a cloud computing company. 4. EASY STORAGE Servers and digital storage devices take up space. Some companies rent physical space to store servers and databases because they don’t have it available on site. Cloud computing gives these companies the option of storing data on someone else’s hardware, removing the need for physical space on the front end. 5. NO TECHNICAL SUPPORT RECQUIRED Corporations might save money on IT support. Streamlined hardware would, in theory, have fewer problems than a network of heterogeneous machines and operating systems. 6. SOLUTION TO COMPLEX PROBLEMS If the cloud computing system’s back end is a grid computing system, then the client could take advantage of the entire network’s processing power. CLOUD COMPUTING SERVICES 1. AMAZON WEB SERVICES The Amazon development model involves building Zen virtual machine images that are run in the cloud by EC2. That means you build your own Linux/Unix or Windows operating system image and upload it to be run in EC2. AWS has many pre-configured images that you can start with and customize to your needs. There are web service APIs (via WSDL) for the additional support services like S3, SimpleDB, and SQS. Because you are building self-contained OS images, you are responsible for your own development and deployment tools. AWS is the most mature of the CC options. Applications that require the processing of huge amounts of data can make effective you of the AWS on-demand EC2 instances which are managed by Hadoop. 2. GOOGLE AppEngine GAE allows you to run Python/Django web applications in the cloud.Google provides a set of development tools for this purpose. i.e. You can develop your application within the GAE run-time environment on our local system and deploy it after it’s been debugged and working the way you want it. Google provides entity-based SQL-like (GQL) back-end data storage on their scalable infrastructure (BigTable) that will support very large data sets. Integration with Google Accounts allows for simplified user authentication. 3. MICROSOFT WINDOWS AZURE Azure is essentially a Windows OS running in the cloud.You are effectively uploading and running your ASP.NET (IIS7) or .NET (3.5) application. Microsoft provides tight integration of Azure development directly into Visual Studio 2008. For enterprise Microsoft developers the .NET Services and SQL Data Services (SDS) will make Azure a very attractive option. The Live Framework provides a resource model that includes access to the Microsoft Live Mesh services. CHARACTERSTICS 1.COST Pricing is based on usage-based options and minimal or no IT skills are required for implementation. 2.DEVICE AND LOCATION INDEPENDENCE It enable users to access systems using a web browser regardless of their location or what device they are using, e.g. PC, mobile 3.MULTI-TENANCY This enables sharing of resources and costs among a large pool of users. 4.RELIABILITY This is suitable for business continuity and disaster recovery. 5.SCALABILITY Dynamic (â€Å"on-demand†) provisioning of resources without users having to engineer for peak loads 6.SECURITY It improves due to centralization of data,increased security-focused resources. 7.SUSTANIBILITY This comes through improved resource utilisation, more efficient systems. ADVANTAGES OF CLOUD COMPUTING 1. Ability to scale to meet changing user demands quickly 2. Pay by use. 3. Task oriented 4. Virtually no maintainence due to dynamic infrastructure software. 5. Application and operating system independent. 6. Easy to develop your own web-based applications that run in the cloud. 7. Location of infrastructure in areas with lower costs of real estate and electricity. 8. Sharing of peak-load capacity among a large pool of users ,improving overall utilization. 9. Separation of application code from physical resources. 10. Not having to purchase assets for one time or infrequent computing tasks. 11. Ability to use external assets to handle peak loads. DRAWBACKS OF CLOUD COMPUTING 1. Often limited or no technical support available. 2. Canned solutions such may not be full-featured or too task oriented. 3. When there are technical issues,you may lose access to your data or application. 4. No control. 5. You must have an internet connection. 6. If the company hosting the application goes out of business,you may lose access to your data or application permanently. REFERENCES 1. http://en.wikipedia.org/wiki/Cloud_computing 2. http://communication.howstuffworks.com/cloud-computing1.htm 3. http://communication.howstuffworks.com/cloud-computing2.htm 4. http://en.wikipedia.org/wiki/Cloud_computing_user 5. http://communication.howstuffworks.com/cloud-computing.htm 6. http://communication.howstuffworks.com/cloud-computing.htm/printable 7. http://cloudcadet.com/what-is-cloud-computing/ 8. http://askville.amazon.com/advantages-disadvantages-Web-based-Cloud-Computing- Wave/AnswerViewer.do?requestId=16202235