In a general terms Cloud Computing provides us means of accessing the applications as utilities over the Internet, or we can say that it is for anything that involves delivering hosted services over the internet.
Cloud: The term Cloud it refers to a Network or Internet In other words, we can say that Cloud is something, which is present at remote location. Cloud can provide services over public and private networks, i.e., WAN, LAN or VPN. Applications such as e-mail, web conferencing, etc.
Cloud Computing refers to manipulating, configuring, and accessing the hardware and software resources remotely. It offers online data storage, infrastructure, and application. It allows us to create, configure, and customize the applications within minimum time at low cost.
Hence, the coud Computing is making our business applications mobile and collaborative.
A formal definition follows, The US National Institute of standard (NIST) has come up with a list of widely accepted definitions of cloud computing terminologies and documented it in the NIST technical draft. As per NIST, cloud computing is described as follows: cloud computing is a model for enabling ubiqiutos, convenient, on-demand network access to a shared pool of configurable computing resources (e.g networks, servers, storage, application and services ) That can be rapidly provisioned and release with minimal management effort or service provider expert.
NIST specifies the following five characteristics that a cloud infrastructure must have.
On demand self-service : The compute, storage or cloud platform resources needed by the user of a cloud platform that are self-provisioned or auto-provisioned with minimal configuration. For Ex. Amazon Elastic compute cloud (a popular cloud Plate form) and obtain virtual servers or virtual storage, within minutes.
Broad Network Access: Ubiquitous ( Services or data are available from anywhere) access to cloud application from Desktops, laptops to mobile devices is critical to the success of a cloud plate form. For Ex: cloud services like Amazon, Google and Yahoo! Etc are available world wide via internet. They are also accessible by a wide variety of devices, such as mobile phones, i pads, and PCs.
Resource Pooling: Cloud services can support millions of users, for example: Skype supports more than 27 million concurrent users, while Facebook supported more millions users. Clearly it is impossible to support this no. Of users if each user needs dedicated hardware. Therefore, cloud services need to share resources between users and clients in order to reduce cost.
Rapid Elasticity: A cloud platform should be able to rapidly increase or decrease computing resources as needed. For Ex: in Amazon EC2, here it is possible to specify a micro instance as well as maximum or large instances (virtual servers) to be allocated.
Measured service: Cloud computing is the ability to “pay as you go” or pay per use. It means, the consumer pays only for the resources that are actually used by his applications. For Ex: AWS, it charges on the basis of per hour on resources which will usage.
So, as per above we can say that in general term ‘ cloud computing promises several attractive benefits for business or enterprise IT and end users . There are most important benefits from above.
- Remotely hosted: Services or data are hosted on a remote infrastructure.
- Ubiquitous: Services or data are available from anywhere.
- Self-service provisioning
- Pay per use or Com modified: The result is a utility computing model similar to traditional utilities, like gas and electricity; you pay for what you need.
Evolution of cloud computing
The concept of Cloud Computing came into existence in the year 1950 with implementation of mainframe computers, accessible via thin/static clients. Since then, cloud computing has been evolved from static clients to dynamic ones and from software to services. Show in figure.
Note: To Understand the concept of Cloud computing you have to know these thing and understand too. First, the definition of cloud computing have been described. And next the major four cloud deployment models (Private cloud, Public Cloud, Community cloud, Hybrid Cloud ) and Service models in cloud computing (SaaS, PaaS, IaaS ) are described in below. So ‘Go ahed – enjoy the cloud technology’
Cloud ‘Deployment and Service’ Models
There are certain services and models working behind making the cloud computing feasible and accessible to end users.
Deployment models define the type of access to the cloud, i.e., how the cloud is located? Cloud computing has defined four deployment models for clouds namely
Public Cloud: The public cloud allows systems and services to be easily accessible over a network that is open for public use.
Or we can say that (public cloud) A service providers makes resources, such as application and storage, available to the general public over the internet. Public cloud services may be free or offered on a pay-per-usage model like Amazon Web Services (AWS), Microsoft and Google own and operate the infrastructure at their data center and access is generally via the Internet.
Private Cloud: A private cloud provides more control over the company’s data and this is under the control of the company’s IT department.
Community cloud: The community cloud allows systems and services to be accessible by a group of organizations.
Hybrid Cloud: The hybrid cloud is a combination of two or more clouds (private, community or public) public and private cloud, in which the critical activities are performed using private cloud while the non-critical activities are performed using public cloud. Hybrid cloud offering the benefits of multiple deployment models.
Cloud computing is based on service models. These are categorized into three basic service models which are Iaas (Infrastructure as a Service), PaaS (Plate form as a Service), SaaS (Software as a Service)
This is the service model on which you will host your applications, for example IaaS, PaaS or SaaS. Each of these service models requires various levels of support and responsibilities once a system is deployed to the platform. To resolve the future challenges that you might encounter you need to understand the models carefully. Other than the service model, the second, you need to decide whether you want a Private or On-Premise cloud, or you want your application to be deployed on a PublicCloud.
Every service model offers you some kind of resource required to operate the most web-enabled systems imaginable.
- IaaS: Infrastructure as a service, it provides the infrastructure in terms of hardware like memory, processor, etc or we can say in general term it allow to configure, virtual server, storage, network.
IaaS offer computers—physical or (more often) virtual machines—and other resources. IaaS refers to online services that abstract the user from the details of infrastructure like physical computing resources, location, data partitioning, scaling, security, backup etc.
Note: IaaS allows to setup & configure operating systems, Applications and it’s settings. e.g- server, storage, network (VPC, Security groups, etc), Virtual Machine etc
- PaaS: Platform as a Service, it provides cloud application platform for the developers or provides the run-time environment for applications, development and deployment tools, etc.
Platform as a Service (PaaS) consumers do not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but have control over the deployed applications and possibly configuration settings for the application-hosting environment.
Note: PaaS allows to configure Applications and settings. e.g- Development tools, Web-server, Database etc
SaaS: Software as a Service, it provides user access directly to the cloud applications without installing anything on the systems. In general SaaS model allows to use software applications as a service to end-users.
Note: SaaS allows to configure only application settings. e.g- email, game, Virtual desktops etc
Benefits of a cloud:
- Lower costs, “Pay as you use”
- Software updates
- Data hosted centrally
- Fail over
- Monitoring services
- Data storage
There are many reasons why cloud computing is so widely popular:
- Reduction of costs
- Universal access
- Software updates
Go ahed – enjoy the cloud technology ! keep learning !