Cloud Computing is a "daily spoken" & most commonly used terminology in every forum.
The cloud has long since ceased to be an emerging technology, and there is no longer any convincing required for enterprise to understand its virtue. While there is clarity on its value, its versatility is still being discovered by most early adopters.
Cloud computing can simply be described as computing offered as utility service delivered via internet.
By definition, "Cloud computing models are for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction," according to NIST.
Characteristics of Cloud Computing:
Essentially, cloud computing as a form of enterprise process is characterised by certain clearly distinctive features. These lend it extremely scalable and agile for enterprise needs. The on-demand self- service allows process flexibility, while broad network access and the ability of pooling resources along with the rapid elasticity by which it can be scaled add value to its ROI. Of course, the biggest advantage to a cloud adoption comes from the cost savings that the measured service model provides.
This is the characteristic that distinguishes a cloud based infrastructure from a physical infrastructure for IT- and that is the layer that can be the biggest cost savings with its pay as you go cloud computing models.
Based on the layer in which the cloud service is consumed, Cloud computing can be classified as Infrastructure As A Service (IaaS), Platform As A Service (PaaS) & Software As A Service (SaaS)
Infrastructure as a Service is a provision model in which an organization outsources the IT requirements as a whole – the equipment used to support operations, including storage, hardware, servers and networking components. Infrastructure as a service allows the flexibility of using the precise amount of cloud space in a public cloud as needed by the enterprise, and the flexibility to pay only for that. The service provider is responsible for housing, running and maintaining it. And the enterprise user pays as per use.
IaaS can be further classified into 4 types as Private cloud, Public cloud,Hybrid cloud, Community cloud based on base design & implementation of the solution. A cloud is called a "public cloud" when the services are rendered over a network that is open for public use. Public cloud services may be free or offered on a pay-per-usage model. Amazon Web Service's public cloud leads the pack here.
It is immediately clear that if an enterprise will claim a corner of the public cloud, there will need to be some extra security processes in place, since the cloud is a multi-tenancy space. So, the responsibility of the security rests both with the vendor as well as the user enterprise. Due to the rapidly evolving nature of the cloud landscape, as also the threats coupled with the newer means of accessing data, the process of security implementation is an iterative and evolving exercise. Devising the best possible strategy and implementing it at multiple layers, therefore, becomes a shared responsibility.
To obtain complete clarity on this division of responsibility, the SLAs on the engagement between the vendor and the enterprise have to be clearly laid down. The vendors are responsible for all the hard layers of infrastructure and the physical devices beneath, as well as the hypervisor or the virtualization layer. The enterprise customer, on the other hand, is responsible for the operating system's security and the applications that run on the operating system. The soft layer houses the networking applications, so the network security is also the enterprise's responsibility.
Thus divided, the security of a cloud infrastructure can be completely covered. Of course, some baseline security features need to be a part of the cloud implementation and are provided by the vendor, but more on that in our next blog.
Also read Baseline Cloud Security - an Absolute Imperative