Cloud Computing is used to describe a new class of network based computing that takes place over the Internet. A collection/group of integrated and networked hardware, software and Internet infrastructure (called a platform). Using the Internet for communication and transport provides hardware, software and networking services to clients.
Cloud computing is an umbrella term used to refer to Internet based development and services. In addition, the platform provides on demand services, that are always on, anywhere, anytime and any place. Pay for use and as needed, elastic scale up and down in capacity and functionalities The hardware and software services are available to general public, enterprises, corporations and businesses markets.
A number of characteristics define cloud data, applications services and infrastructure:
- Remotely hosted: Services or data are hosted on remote infrastructure.
- Ubiquitous: Services or data are available from anywhere.
- Commodified: The result is a utility computing model similar to traditional that of traditional utilities, like gas and electricity – you pay for what you would want!
Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. Cloud computing customers do not own the physical infrastructure. Cloud computing users avoid capital expenditure (CapEx) on hardware, software, and services when they pay a provider only for what they use. Low shared infrastructure and costs, low management overhead, and immediate access to a broad range of applications.
A service model that involves outsourcing the basic infrastructure used to support operations–including storage, hardware, servers, and networking components. The service provider owns the infrastructure equipment and is responsible for housing, running, and maintaining it. The customer typically pays on a per-use basis. The customer uses their own platform (Windows, Unix), and applications.
A service model that involves outsourcing the basic infrastructure and platform (Windows, Unix). PaaS facilitates deploying applications without the cost and complexity of buying and managing the underlying hardware and software where the applications are hosted. The customer uses their own applications.
Also referred to as “software on demand,” this service model involves outsourcing the infrastructure, platform, and software/applications. • Typically, these services are available to the customer for a fee, pay-as-you-go, or a no charge model. The customer accesses the applications over the internet.
Common Characteristics of Cloud Computing
What is the purpose and benefits of Cloud Computing?
Cloud computing enables companies and applications, which are system infrastructure dependent, to be infrastructure-less. By using the Cloud infrastructure on “pay as used and on demand”, all of us can save in capital and operational investment! Clients can put their data on the platform instead of on their own desktop PCs and/or on their own servers. They can put their applications on the cloud and use the servers within the cloud to do processing and data manipulations etc.
Some Commercial Cloud Offerings
Opportunities and Challenges
The use of the cloud provides a number of opportunities: It enables services to be used without any understanding of their infrastructure. Cloud computing works using economies of scale: It potentially lowers the outlay expense for start up companies, as they would no longer need to buy their own software or servers. Cost would be by on-demand pricing.
Vendors and Service providers claim costs by establishing an ongoing revenue stream. Data and services are stored remotely but accessible from “anywhere”.
Advantages of Cloud Computing
Lower computer costs: You do not need a high-powered and high-priced computer to run cloud computing’s web-based applications. Since applications run in the cloud, not on the desktop PC, your desktop PC does not need the processing power or hard disk space demanded by traditional desktop software. When you are using web-based applications, your PC can be less expensive, with a smaller hard disk, less memory, more efficient processor. In fact, your PC in this scenario does not even need a CD or DVD drive, as no software programs have to be loaded and no document files need to be saved.
Reduced software costs: Instead of purchasing expensive software applications, you can get most of what you need for free-ish! most cloud computing applications today, such as the Google Docs suite. Better than paying for similar commercial software which alone may be justification for switching to cloud applications.
Improved document format compatibility: You do not have to worry about the documents you create on your machine being compatible with other users’ applications or OSes There are potentially no format incompatibilities when everyone is sharing documents and applications in the cloud.
Unlimited storage capacity: Cloud computing offers virtually limitless storage. Your computer’s current 1 Tbyte hard drive is small compared to the hundreds of Pbytes available in the cloud.
Increased data reliability: Unlike desktop computing, in which if a hard disk crashes and destroy all your valuable data, a computer crashing in the cloud should not affect the storage of your data. If your personal computer crashes, all your data is still out there in the cloud, still accessible. In a world where few individual desktop PC users back up their data on a regular basis, cloud computing is a data-safe computing platform!
Disadvantages of Cloud Computing
Requires a constant Internet connection: Cloud computing is impossible if you cannot connect to the Internet. Since you use the Internet to connect to both your applications and documents, if you do not have an Internet connection you cannot access anything, even your own documents.
Does not work well with low-speed connections: Similarly, a low-speed Internet connection, such as that found with dial-up services, makes cloud computing painful at best and often impossible. Web-based applications require a lot of bandwidth to download, as do large documents.
Features might be limited: This situation is bound to change, but today many web-based applications simply are not as full-featured as their desktop-based applications. For example, you can do a lot more with Microsoft PowerPoint than with Google Presentation’s web-based offering. A dead Internet connection means no work and in areas where Internet connections are few or inherently unreliable, this could be a deal-breaker.
Stored data might not be secure: With cloud computing, all your data is stored on the cloud. The questions is How secure is the cloud? Can unauthorized users gain access to your confidential data?
Stored data can be lost: Theoretically, data stored in the cloud is safe, replicated across multiple machines. But on the off chance that your data goes missing, you have no physical or local backup. Put simply, relying on the cloud puts you at risk if the cloud lets you down.