The term “Cloud Computing” refers to the delivery of hosted services to the clients over the Internet. With cloud computing the companies can consume a computing resource like a Virtual Machine, a software application or storage capacity as a utility, like electricity instead of having them investing on the computing infrastructure like machines, storage capacity or even applications. Obviously, cloud computing has resulted in great savings for user companies and has allowed them to focus on their main activities rather than investing and maintaining in the computing infrastructure.
Types of Cloud Computing Services
Broadly, the cloud computing services fall in three service categories. These are Infrastructure as a Service (IaaS), Software as a Service (SaaS) and Platform as a Service (PaaS).
The IaaS providers provide an instance of virtual server and storage and APIs allowing the users to migrate their jobs to Virtual Machine. Users are also provided storage capacity and can independently run or configure the virtual machine and storage, as they want. IaaS providers can provide required size of memory and customised or optimised instances to suit different workloads.
SaaS delivers software applications, known as web services, over the Internet. Email services are the examples of SaaS. The users can access these services using a mobile device or a computer from any place with internet access.
In case of PaaS services, the providers host the development tools on their servers and the users can access the tools over the internet via web portals and gateway software. It has application in general software development and PaaS cloud providers develop the software and host. Google App Engine is an example of PaaS.
Deployment models for Cloud Computing
Cloud computing can be deployed as public, private or hybrid models.
In the Public cloud model, the cloud service providers offer cloud services over the Internet. These sold on demand usually in few minutes or hours, but also with long-term commitments available for some services. Customers are charged based on actual CPU cycles, bandwidth or storage they consume. Examples of Public cloud providers are IBM, MS Azure and Google Cloud Platform.
Private cloud services are provided to the internal users of a business from its data center. This model is very versatile and convenient as the business preserves its control, management, and security. OpenStack and VMWare are popular vendors of private clouds.
Hybrid cloud is combination of private cloud and public cloud services with an implementation of automation between these two. Hybrid cloud can be used to create unified, scalable and automated environment, which takes advantage of public cloud infrastructure and maintains its control over business mission-critical data.
Cloud Computing Security
Security is the main concern in adopting cloud-computing platforms. This is more of a concern in public clod computing adoption. The reason for this is that the public cloud providers share the hardware infrastructure among numerous customers as it a multi-tenant environment. Such an environment must be provided with a strong isolation between various logical computing resources. The login credentials manages access to the public cloud storage and the computing resources. Any lapse on security measures on the part of the cloud providers presents a serious risk to the shared users of these services. Because of complex regulatory requirements and the standards of governance, many organisations are hesitant to keep data or the workloads on public cloud for the risk due to loss, theft or outages. However, over the years, it is seen that these platforms have gained the trust of business organisations because of reliable logical isolation they have offered along with use of technology of encryption and reliable access and identity management.