Types Of Cloud Computing

Published Date: 02 Nov 2017

Today everyone is speaks about cloud computing, but no one the gives exact meaning to it. There is a general idea behind the cloud where business functions exist somewhere in remote place and the business is in other place and companies started looking it to use technology. Cloud computing has an advantage for the businesses to increase their IT functionality without adding extra infrastructure, and software.

3.1.1 Types of Cloud Computing

Cloud Computing can be classified under 4 types based on location where the cloud is hosted:

Public Cloud: Computing infrastructure is hosted at the vendor’s premises. The customer has no visibility over the location of the cloud computing infrastructure. The computing infrastructure is shared between organizations.

Private Cloud: Computing architecture is dedicated to the customer and is not shared with other organizations. They are expensive and are considered more secure than Public Clouds. Private clouds may be externally hosted ones as well as in the premise hosted clouds.

Hybrid Cloud: Organizations host some critical, secure applications in private clouds and not-so-critical applications in the public cloud. The combination is known as Hybrid Cloud. Cloud bursting is used to define a system where the organization uses its own infrastructure for normal usage and cloud is used for peak loads.

Community Cloud: The cloud infrastructure is shared between the organizations of the same community. For example, all the government agencies in a city can share the same cloud but not the non government agencies.

Six various types of cloud computing and their offereing to businesses are listed below:

WWW based cloud computing service is a type of cloud service that exploits certain web service functionality, rather than deploying applications, for example, it can use Google Maps API.

Software as a Service is an idea, where an application can be used by multiple tenants, using the browser. Example SaaS solutions are used in Sales, ERP and HR.

Platform as a Service is a variant of SaaS, one can run their own applications but is executed on the cloud provider’s infrastructure.

Utility cloud computing services offer virtual storage and server options, where the companies can access it on-demand. This allows easy creation of virtual data center.

Managed services are the oldest cloud computing solutions. In this, a cloud computing provider utilizes an application than end customers. Examples are using anti-spam services and application monitoring.

Service commerce is a mix of SaaS and managed services. It provides a hub of services where end-user interacts. Examples are tracking the expense happened, virtual assistant services and travel ordering.

3.1.2 Public cloud

A public cloud is based on the standard cloud computing model, where service provider makes the resources like storage and applications available to all over the WWW. These services may be free or on a pay-per-usage model. The advantages of using a public cloud computing service are:

Inexpensive and easy setup.

Scalability.

No resources are wasted.

Examples are Amazon Elastic Compute Cloud (EC2), IBM's Blue Cloud, Sun Cloud, Google AppEngine and Windows Azure Services Platform.

3.1.3 Private Cloud (Internal Cloud or Corporate Cloud)

Private cloud is a proprietary computing model that provides services hosted to the people who are behind a firewall.

Advances in distributed computing and virtualization allowed administrators of network and data centers to provide effective services that meet the needs of their "end-users" inside the organization.

3.1.4 Difference between public cloud and a private cloud

Cloud computing and storage are not a new topics. Cloud is one of the most recognized terms for the industry. During the initial stages, it was offered as a service, which earned recognition with Web 2.0. With the evolution of the technology to the level today, cloud can be offered in two types, the public cloud hosting and the private cloud services. We differentiate between public cloud and private cloud and also, users would be able to understand the difference based upon various factors such as a pattern of usability, security, and performance, which is insignificance with the costs.

3.1.5 Public Vs Private Clouds

It is easy to distinguish the private and the public cloud. The location of Cloud's deployment will be the first question. Cloud offering as a service over the WWW is a Public Cloud, whereas a private cloud is the deployment within the Firewall. The location of deployment is the main factor between the two.

Public cloud is charged on the month to month basis. Users have to pay for the usage per GB plus bandwidth transfer fees. It is based on-demand storage scalability and customer no need to buy storage hardware.

Private cloud is created using software’s operating on a hardware provided by the customer. The storage is shared only inside the organization and is controlled entirely by the enterprise. Because of scalability, customers can add servers to the existing architecture. Furthermore, this architecture is fully-managed by the customers.

3.1.5 Factors for Public Vs. Private Cloud

Elementary Expense

Private Cloud architecture does not require a very large investment, it can be built at a low budget also deploying the architecture is easy manner. Public Cloud Hosting is offered at an affordable price of Rs.3000. Since users are not required to buy hardware or software, the initial expenditure is trivial.

Volume of Data

Cloud storage is primarily reputed for its extensive scalability features but most of the companies start in small scale. Private cloud can initiate from few TB’s in size also offering scalability out of capacity by adding additional nodes, whereas, the public clouds start even smaller. Public clouds make it simple to back up a single laptop or deploy an application of a few GBs.

Performance Expectations

The deployment of private clouds is within the firewall and accessible using an Ethernet. Every addition of nodes increases the performance for this type of cloud. The only limitation to Public cloud accessibility is via an Internet.

Other factors include i) Duration of Data Storage, ii) Access Patterns and Locations, iii) Security and Data Isolation, iv) Confidentiality and Destruction of Data, v) SLA’s-Service Level Agreements and vi) In-House Technical Crew.

3.2 Cloud Infrastructure

3.2.1 Cloud Computing Infrastructure:

Ideal for Everything from Online Sports Betting to Major Corporations

A description...

Fig. 5: Cloud Computing Infrastructure

Cloud computing infrastructures work a lot, like an electricity grid. When you need light in a room, you flip the light switch, that signal travels through the electricity grid, then power is sent to your switch and you have been light. When you demand power, it comes to you via the grid. A cloud computing infrastructure works the same way. Whenever you need resources such as information and software, they are stored in a network called a cloud. You can find it in your cloud computing infrastructure and pull it up. If someone is in need of that same resource, then he or she can access it at that computer itself. Information is stored in the cloud computing infrastructure instead of on the computer. Figure 5 shows the basic infrastructure for a cloud, comprising of client and server machines. Application, Platform and Infrastructure services are used by the two machines. Server will deploy the services and acts as a provider, whereas a client uses it and acts as a requestor.

Any business that requires multiple computers could benefit from a cloud computing infrastructure. Anything from online sports betting companies to major corporations with operations around the world can personalize a cloud computing infrastructure to meet their specific needs. It eliminates the need for individual employees to back up data regularly, because the network administrator would be responsible for backup data on the cloud computing infrastructure. It also allows each employee to access the same information, which makes operations run much more efficiently in an office setting.

One can get cloud computing infrastructure for his business, within five steps they are:

1. Choose on-demand technology that will be the foundation for your infrastructure.

2. Determine how employees can access the information about the infrastructure.

3. Prepare the infrastructure with the necessary software and hardware.

4. Set up each computer to access the infrastructure.

5. Integrate all aspects of the infrastructure so all employees can participate in resource sharing.

Setting up a cloud computing infrastructure does take an investment but improved efficiency will make it worthwhile.

3.2.2 Status of Cloud Computing in India

India is the outsourcing capital of the world but when it comes to offering cloud services, its record is spotty at the best. There are some companies in the application space and platforms space but they are a very small fraction of the service market in India. Because of infrastructure services are capital intensive and also due to the unreliable infrastructure like electricity, network, etc. in India the growth of cloud computing services lagged.

The potential for Infrastructure market in India is huge. For example, India may have 1.6 million developers, over 12000 system integrators and more than 1400 independent software vendors along with millions of other businesses of all sizes and shapes trying to take advantage of IT in the growing economy. They all want to take advantage of zero capital cloud infrastructure services. Moreover, Indian regulators are unpredictable and recommend to store the data inside the country’s borders.

Tata Communications, India’s leading service provider, announced an expansion of their cloud offerings, making it the first comprehensive India based cloud solution available for customers. In addition to the existing services, they added Instacompute and Instaoffice in their list of service offerings. This new services marks the company’s expansion in the cloud space to deliver self-service, pay-as-you-use IT application and data center infrastructure services.

3.2.2.1 Tata Communications offers India’s home-grown infrastructure services.

The long wait for many users in India is over. By offering a metered on-demand service like Amazon EC2, Tata Communications is catering to the needs of both SMEs and big enterprises. Their new compute and storage service, called Instacompute, comes with free load balancers, firewall, public IP address, etc. They have an aggressive pricing strategy, which could potentially help them compete with Amazon Web Services in the international market.

Their other offering, called Instaoffice is just a repackaging of Google Apps. From Tata Communications point of view, this allows them to sell full cloud stack to their customers. For Google, they are a good channel partner, who can help push Google Apps deeper into the Indian market. So, there is nothing interesting in this part of the announcement.

The positive side of this announcement is that Indian customers get an infrastructure service offering hosted in India. It not only solves their problem of having to deal with foreign exchange issues. It will also help them be compliant to any government regulations (present and future).

The negative side comes from the international angle. During the outsourcing, there was news about employees of the outsourcing firms abusing the business data about their customers. The possibility for such security and privacy problems from the insiders will hinder their growth in the international market.

3.3 Cloud Application Architectures

Cloud computing is a relatively new way of referring to the use of shared computing resources. Cloud computing group's together large numbers of compute servers and other resources and typically offer their combined capacity in terms of on-demand and pay-per-cycle. The end users on a cloud computing network usually have no idea, where the servers are physically located.

Cloud computing is fully enabled by virtualization (hypervisors). A virtualized application is an application that is bundled with all the components that it needs to run, along with a streamlined operating system.

This flexibility is the advantage to cloud computing and distinguishes it from other forms of computing such as grid or utility and SaaS. The ability to launch new instances of an application with minimal labor and expense allows application providers to:

• Scale up and down rapidly

Increased fault tolerance

• Bring up development or test instances

• Faster new versions to the customer base

• Load and test an application

Once you’ve decided to offer your application in a cloud computing environment, it is important to avoid the "success disaster." When your application becomes popular overnight, it may crash under the unanticipated load. So designing the application for the cloud at the outset to take maximum advantage of the cloud environment is important.

3.3.1 Architectural Considerations

Designing an application to run as a virtual appliance in a cloud computing environment is very different than designing it for an on-premise or SaaS deployment. We discuss the following considerations. To be successful in the cloud, an application must be designed to scale easily, tolerate failures and include management tools.

Scale

Cloud computing offers the potential for nearly unlimited scalability, as long as the application is designed to scale from the outset. The best way to ensure this is to follow some basic application design guidelines are discussed below:

Start simple

Avoid complex design and performance enhancements or optimizations in favor of simplicity. It’s a good idea to start with the simplest application and rely on the scalability of the cloud to provide enough servers to ensure good application performance.

Split application functions and couple loosely

Use separate systems for different pieces of application functionality and avoid synchronous connections between them. Again, as demand grows, you can scale each one independently instead of having to scale the entire application, when you hit a bottleneck. Network communication

Design the application to use network-based interfaces and not interprocess communication or file-based communication paradigms. This allows you to effectively scale in the cloud because each piece of the application can be separated into distinct systems.

Deployment Cluster

Rather than scale a single system up to serve, all users, consider splitting your system into multiple smaller clusters, each serving a fraction of the application load. This is often called "sharing" and many web services can be split up along one dimension, either users or account. The advantages of cloud computing when it comes to scalability are:

Inexpensive testing

Testing can be done against a test cluster without risking the performance or integrity within the production system.

Reduced risk

Bring up a test instance of the cluster to prove a new code base and roll out a new version with one cluster at a time.

Ability to segment the customer base

Use clusters to separate customers with varying demands, such as a large customer who wants a private instance of the application, or one who requires extensive customizations.

Auto-scaling based on application load

With the ready availability of resources, applications can be built to recognize when they are reaching the limits of their current configuration and automatically bring up new resources.

Fail

Inevitably, an application will fail, no matter, what its environment. When you design on premise or SaaS application, you typically consider several "doomsday" scenarios.

Get back up quickly

Automate the launching of new application clusters in order to recover quickly. Application components must be able to come up in an automated fashion, configure them and join the application cluster. Cloud computing provides the ideal environment for this fast start up and recovery process.

Data considerations

When an application fails, data persistence and system state cannot be taken for granted. To ensure data preservation, move all data on persistent storage and make sure it is replicated and distributed. The system state is stored and used for the recovery process and the system can be restarted from the point of failure.

Test your "doomsday" scenario: Cloud computing makes it easy to bring up an instance of your application to test various failure scenarios. Because of the flexible nature of cloud computing, it is possible to simulate many different failure scenarios at a very reasonable cost. Single instances of a system can be taken off-line to see how the rest of the application will respond. Likewise, multiple recovery scenarios can be planned and executed ahead of any real production failure.

Be aware of the real cost of failure:

Of course, the ideal situation is avoiding any application failure but what is the cost to provide that assurance? A large internet company once said that they could tolerate failure as long as the impact was small enough so that it is not noticeable to the overall customer base.

3.3.1.4 Manage

Deploying cloud applications as virtual appliances make management significantly easier. The appliances should bring with them all the software that they need for their entire life cycle in the cloud. More important, the aspect is that it should be built in a systematic way, akin to an assembly-line production effort in contrast to a hand-crafted approach. The reason for this systematic approach is the consistency of creating and re-creating images.

When building appliances, they should contain the operating system and any middleware components they need. When appliances are installed in the cloud, they should also plug into a monitoring and management system.

The management system plays an important role in the testing and deployment process. To include testing, management system allows us to bring up a test cluster, conduct any testing that is required and then migrate the tested application into production.

Finally, by automating the creation and management of these appliances, one can tackle the most difficult and expensive problem called variability. By producing a consistent appliance image and managing it effectively, variability is removed from the release management and deployment process. Reducing the variability reduces the chances of mistakes.

The advantages of designing the application in the cloud include:

• Cost reduction

• Reduced overhead

• Eliminates application sprawl

• Reduces the chance for mistakes.