CLOUD COMPUTING

Don’t be confused by the expression “cloud services, you are probably already using them if you use Amazon, Gmail, Hotmail, or Facebook. All it means is that your data is stored virtually.

 

Cloud computing is the delivery of hosted services over the Internet .The origin of the term cloud computing is not known but it may be based on practice of using drawings of clouds to denote networks in diagrams of computing and communications systems.

Cloud computing provides easy, scalable access to computing resources and IT services. It can be thought of as similar to a utility like an electricity grid, delivered over a network .It involves the sharing of resources, services and infrastructure and can often be very cost effective.

Amazon played a key role in the development of cloud computing by modernizing their data centers, which were using a fraction of their capacity . The new cloud architecture gave significant efficiency improvements and small, fast-moving teams could add new features faster and more easily. Amazon then developed a product that could provide cloud computing to external customers, and launched Amazon Web Service on a utility computing basis in 2006.

Cloud computing exhibits the following key characteristics:

1. Agility improves with users' ability to re-provision technological infrastructure resources.
2. Application programming interface (API) accessibility to software that enables machines to interact with cloud software in the same way that a traditional user interface (e.g., a computer desktop) facilitates interaction between humans and computers. Cloud computing systems typically use Representational State Transfer (REST)-based APIs.
3. Cost: cloud providers claim that computing costs reduce. A public-cloud delivery model converts capital expenditure to operational expenditure. This purportedly lowers barriers to entry, as infrastructure is typically provided by a third party and does not need to be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is fine-grained, with usage-based options and fewer IT skills are required for implementation (in-house). The e-FISCAL project's state-of-the-art repository contains several articles looking into cost aspects in more detail, most of them concluding that costs savings depend on the type of activities supported and the type of infrastructure available in-house.
4. Device and location independence enable users to access systems using a web browser regardless of their location or what device they use (e.g., PC, mobile phone). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.
5. Virtualization technology allows sharing of servers and storage devices and increased utilization. Applications can be easily migrated from one physical server to another.
6. Multitenancy enables sharing of resources and costs across a large pool of users thus allowing for:
• centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)
• peak-load capacity increases (users need not engineer for highest possible load-levels)
• utilisation and efficiency improvements for systems that are often only 10–20% utilised  
7. Reliability improves with the use of multiple redundant sites, which makes well-designed cloud computing suitable for business continuity and disaster recovery. 
8. Scalability and elasticity via dynamic ("on-demand") provisioning of resources on a fine-grained, self-service basis in near real-time(Note, the VM startup time varies by VM type, location, os and cloud providers), without users having to engineer for peak loads. 
9. Performance is monitored, and consistent and loosely coupled architectures are constructed using web services as the system interface. 
10. Security can improve due to centralization of data, increased security-focused resources, etc., but concerns can persist about loss of control over certain sensitive data, and the lack of security for stored kernels. Security is often as good as or better than other traditional systems, in part because providers are able to devote resources to solving security issues that many customers cannot afford to tackle. However, the complexity of security is greatly increased when data is distributed over a wider area or over a greater number of devices, as well as in multi-tenant systems shared by unrelated users. In addition, user access to security audit logs may be difficult or impossible. Private cloud installations are in part motivated by users' desire to retain control over the infrastructure and avoid losing control of information security. 
11. Maintenance of cloud computing applications is easier, because they do not need to be installed on each user's computer and can be accessed from different places.

The National Institute of Standards and Technology's definition of cloud computing identifies "five essential characteristics":

1. On-demand self-service. A consumer can unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with each service provider. 
2. Broad network access. Capabilities are available over the network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms (e.g., mobile phones, tablets, laptops, and workstations). 
3. Resource pooling. The provider's computing resources are pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to consumer demand. 
4. Rapid elasticity. Capabilities can be elastically provisioned and released, in some cases automatically, to scale rapidly outward and inward commensurate with demand. To the consumer, the capabilities available for provisioning often appear unlimited and can be appropriated in any quantity at any time.
5. Measured service. Cloud systems automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service.
   —National Institute of Standards and Technology

To be successful, Companies today need to compete in the global economy and keep up with the pace of innovation. Their IT departments must be agile when responding to changing business needs, and must optimise efficiency and manage costs while enabling their business to stay productive. Cloud computing is one of the key technology trends creating opportunities to address these needs.

Private or Public Cloud.

• A public cloud sells services to anyone on the Internet. An example is Amazon Web Services which is thought to be currently the largest public cloud provider.

• A private cloud is a privately owned network or a data centre that supplies hosted services to a limited number of clients.

When a service provider uses public cloud resources to create their private cloud, this is known as a virtual private cloud.

A hybrid cloud or hybrid IT is a composition of at least one private cloud and at least one public cloud. Some resources are managed in-house and others are provided externally. For example, an organization might use a public cloud service, such as Amazon Simple Storage Service (Amazon S3) for archived data but continue to maintain in-house storage for customer data that is still active. This hybrid approach takes advantage of the scalability and cost-effectiveness that a public cloud environment offers without exposing critical applications and data to third-party vulnerabilities.

Cloud services are broadly divided into three categories:

• Infrastructure-as-a-Service (IaaS),

• Platform-as-a-Service (PaaS)

• Software-as-a-Service (SaaS).

Infrastructure-as-a-Service allows users to start, stop, and access and configure their virtual servers and storage. An example is Amazon Web Services. A user will pay for only the capacity that is needed, and can bring more online when required. Because this pay-for-what-you-use model resembles the way electricity, fuel and water are consumed, it’s sometimes referred to as utility computing.

Platform-as-a-service is a set of software and product development tools hosted on the provider’s infrastructure. An example is GoogleApps. Developers create applications on the provider’s platform.

Software as a service providers manage the infrastructure and platforms on which the applications run. It is sometimes referred to as “on-demand software” and is usually priced on a pay-per-use basis, often using a subscription fee. Examples 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 from anywhere.

SaaS can usually help business to reduce IT operational costs by outsourcing hardware and software maintenance and support to the cloud provider. This reduces their requirement for hardware/software spending and personnel expenses. Because applications are hosted centrally, updates can be released without users having to install new software. A potential downside is that the users’ data are stored on the cloud provider’s server,so there could be unauthorized access to the data.

Cloud Backup or Online Backup
Cloud backup or online backup allows data to be backed up by sending a copy of the data over a network to an off-site server The server is often hosted by a third-party service provider, who charges the customer a fee based on capacity, bandwidth or number of users.

Online backup systems often run on a schedule determined by the level of service the customer has purchased. If the customer has purchased an option for daily backups then the application collects, compresses, encrypts and transfers data to the service provider’s servers every 24 hours. To reduce the amount of bandwidth consumed and the time it takes to transfer files, the service provider might only provide incremental backups after the initial full backup.

Third-party cloud backup is extremely popular with small offices and home users because of its convenience. There is no spend on additional hardware and backups run automatically without manual intervention.

Traditional backup is a better solution for critical data that requires a short recovery time because there are physical limits governing how much data can be moved over a network in a given amount of time. If a large amount of data needs to be recovered, it may need to be shipped on tape or some other portable storage media.

Backupcharacteristic	Use Cloud storage and backup	Use Traditional backup
Amount of data	When the total amount of datato be protected is less than 100 GB per 1 Mb of network bandwidth. For example, 100 GB can be supported by a 1 Mb WAN connection	For large amounts of data, or when there is limited network connectivity,so traditional backup is more appropriate.
Rate of change	Use when the rate of change of the data is less than 10% of the total data per month.	For data that changes frequently, it may be more appropriate to use traditional backup methods that use local disk and tape, with off-site tape transport

The Cloud OS

Microsoft has developed a platform named “the Cloud OS,” which addresses this technology.

This delivers a platform of products and services that enables companies to;-

• transform their current infrastructure to an elastic, scalable, and reliable infrastructure;

• quickly and flexibly build and manage modern applications across platforms, locations, and devices;

• unlock insights from new and existing data;

• Support user productivity on whatever device they choose, wherever they use it.

The heart of the Microsoft Cloud OS is Windows Server 2012, which delivers in four ways:

• It goes beyond virtualization to provide maximum flexibility for delivering and connecting to cloud services.

• It delivers the power of many servers with the simplicity of one:

• It opens the door to every app on any cloud: it is a broad, scalable, and elastic server platform that gives organizations the flexibility to build and deploy applications and websites on-premises, in the cloud, and in a hybrid environment, using a consistent set of tools and frameworks.

• It enables a contemporary work style: provide users with flexible access to data and applications from virtually anywhere, on virtually any device, with a rich user experience, while simplifying management and helping maintain security, control, and compliance.

Microsoft Private Cloud Fast Track is a joint project between Microsoft and its hardware partners to deliver pre-configured solutions that reduce the complexity and risk of implementing a private cloud. It is Based on Windows Server, and delivers flexibility and choice across a range of hardware vendor options technologies.

Case studies
A manufacturing company was able to Improve IT Service Delivery and Efficiency with Microsoft’s Hyper-V Private Cloud

Business has been tough lately, and many companies need to create a premier product whilst simultaneously lowering the overhead. A company’s IT staff can support this efficiency by moving to Microsoft private cloud software—the Hyper-V technology in Windows Server 2008 R2 and Microsoft System Center 2012. The company will be able to reduce IT inefficiencies and move to a measurable, service-oriented IT model. It can focus its IT staff on new business initiatives rather than on server management and give them a more rewarding work environment. By switching to Microsoft, a company can also gain software licensing efficiencies that save money and provide more flexibility

In another example a Translation Firm Increased Flexibility and Improved Cash flow with a Cloud Solution

In a translation company with a small, office-based team and a wide customer base covering all sectors, the needs of each client vary greatly. The Company has adapted to meet these requirements by developing a global network of specialised remote workers. With Microsoft Office 365, the firm has improved cash flow, gained a reliable email system, and is enabling employees to work more flexibly.