Introduction

Welcome to the world of Cloud computing, in this blog, I am going to explain about cloud computing from fundamental to advance.  In this competitive world, many top companies like Amazon, Microsoft, Google, IBM, and Oracle offers cloud services to their client with different price structures and features.  Neverthless, this blog will cover up AWS's (Amazon Web Services) various features and services which were offered by them as i am very much interested to learn AWS and its capabilities.

Below are the few definitions of Cloud computing in Wikipedia and internet, it describes cloud nature and history of it.

"Cloud computing is an information technology (IT) paradigm, a model for enabling ubiquitous access to shared pools of configurable resources (such as computer networks, servers, storage, applications and services), which can be rapidly provisioned with minimal management effort, often over the Internet. Cloud computing allows users and enterprises with various computing capabilities to store and process data either in a privately-owned cloud, or on a third-party server located in a data center - thus making data-accessing mechanisms more efficient and reliable. Cloud computing relies on sharing of resources to achieve coherence and economy of scale, similar to a utility."

“Cloud Computing is on-demand computing resources, delivered to you over the internet”

“Cloud Computing is computing service you traditionally did local (on-premises), now performed remotely, across the internet (off-premises)”

Advocates note that cloud computing allows companies to avoid or minimize up-front IT infrastructure costs. As well, third-party clouds enable organizations to focus on their core businesses instead of expending resources on computer infrastructure and maintenance. Proponents also claim that cloud computing allows enterprises to get their applications up and running faster, with improved manageability and less maintenance, and that it enables IT teams to more rapidly adjust resources to meet fluctuating and unpredictable business demand.Cloud providers typically use a "pay-as-you-go" model. This could lead to unexpectedly high charges if administrators are not familiarized with cloud-pricing models.

In 2009 the availability of high-capacity networks, low-cost computers and storage devices as well as the widespread adoption of hardware virtualization, service-oriented architecture, and autonomic and utility computing led to a growth in cloud computing.Companies can scale up as computing needs increase and then scale down again when demands decrease.  In 2013 it was reported that cloud computing had become a highly demanded service or utility due to the advantages of high computing power, cheap cost of services, high performance, scalability, and accessibility - as well as availability. Some cloud vendors experience growth rates of 50% per year, but while cloud computing remains in a stage of infancy, it has pitfalls that need to be addressed to make cloud-computing services more reliable and user-friendly.

Traits of Cloud

Many forms of Cloud computing

There are many forms of cloud computing in industry those are SaaS (Software as Service), IaaS (Infrastructure as Service), DaaS (Desktop as Service), PaaS (Platform as service) and etc.,

In SAAS, Software is application which is running in the Cloud, we could paying and them in on-demand basis.  For Example: Dropbox, Gmail, SalesForce.com and etc.,

In IAAS, We will access Virtual machine that VM is instance of Physical computer which is running in the Cloud, we could paying and them in on-demand basis.  For Example: Virtual CPU, Memory, Virtual Storage whatever we want.

In PAAS, developers who need access on developer platform in the cloud, we could paying and them in on-demand basis.  For Example: Web Server,  DB Server, Framework for .NET Development and etc.,

In EAAS, developers who need Virtual desktop, backup, network switches, and etc., in the cloud, we could paying and them in on-demand basis.  For Example: Desktop,  Application streaming, Backup, and etc.,

History of Cloud computing

In Past, there were many kind of computing.  However, all these computing services are same as one another in the way of giving computing services to consumers.

Centralized Computing

Centralized computing is computing done at a central location, using terminals that are attached to a central computer. The computer itself may control all the peripherals directly (if they are physically connected to the central computer), or they may be attached via a terminal server. Alternatively, if the terminals have the capability, they may be able to connect to the central computer over the network. The terminals may be text terminals or thin clients, for example.

Grid Computing

Grid computing is the collection of computer resources from multiple locations to reach a common goal. The grid can be thought of as a distributed system with non-interactive workloads that involve a large number of files. Grid computing is distinguished from conventional high performance computing systems such as cluster computing in that grid computers have each node set to perform a different task/application. Grid computers also tend to be more heterogeneous and geographically dispersed (thus not physically coupled) than cluster computers. Although a single grid can be dedicated to a particular application, commonly a grid is used for a variety of purposes. Grids are often constructed with general-purpose grid middleware software libraries. Grid sizes can be quite large.

Distributed Computing

Distributed computing is a field of computer science that studies distributed systems. A distributed system is a model in which components located on networked computers communicate and coordinate their actions by passing messages.The components interact with each other in order to achieve a common goal. Three significant characteristics of distributed systems are: concurrency of components, lack of a global clock, and independent failure of components.Examples of distributed systems vary from SOA-based systems to massively multiplayer online games to peer-to-peer applications.

A computer program that runs in a distributed system is called a distributed program, and distributed programming is the process of writing such programs.There are many alternatives for the message passing mechanism, including pure HTTP, RPC-like connectors and message queues.

On-demand Computing

On-demand computing is a delivery model in which computing resources are made available to the user as needed. The resources may be maintained within the user's enterprise, or made available by a cloud service provider. When the services are provided by a third-party, the term cloud computing is often used as a synonym for on-demand computing.

Hosting

A web hosting service is a type of Internet hosting service that allows individuals and organizations to make their website accessible via the World Wide Web. Web hosts are companies that provide space on a server owned or leased for use by clients, as well as providing Internet connectivity, typically in a data center. Web hosts can also provide data center space and connectivity to the Internet for other servers located in their data center.

Application Service providers (ASP)

An application service provider (ASP) is a business providing computer-based services to customers over a network; such as access to a particular software application (such as customer relationship management) using a standard protocol (such as HTTP).

Time frame of computing