Strategic Provision of Cloud Computing Services

Major Services of Service Provisioning

In cloud computing, in the perspective of resource allocation and service provisioning, the services layers are divided into several working layers. There are then four service layers: the application layer (SaaS), the platform layer (PaaS), the infrastructure layer (IaaS), and security as a service (SecaaS) layer. For the list of acronyms, please refer to the Abbreviations Section. Each of these layers provides a specific service for users, which are explained as follows.

Infrastructure as a Service (IaaS)

Infrastructure as a service, defined as providers who offer computing and storage resource capacity via vitalization, allowing physical resources to be assigned and split dynamically. A typical application could be an on-line alternative to a word processor or spreadsheet. Several types of virtualization occur in this layer. Along with other resources, it includes computing, network, hardware, and storage. At the bottom layer of the framework, infrastructure devices and hardware are virtualised and provided as a service to users to install the operating system (OS) and to operate software applications. Therefore, this layer is called infrastructure as a service (IaaS). The Elastic Computing Cloud of Amazon (Amazon EC2) and storage by both Elastic Book Store (EBS) and Simple Storage Services (S3) are typical services of this layer.

Platform as a Service (PaaS)

Platform as a service, defined as a provider that offers an additional layer of abstraction above the virtualised infrastructure. The provided software platform trades off restrictions on the type of software that can be deployed for built-in scalability PaaS including mobile operating systems such as Android, iPhone, Symbian, and other OSs, as well as database management and IMS. This layer contains the environment for distributing storage, parallel programming design, the management system for organising distributed file systems, and other system management tools for cloud computing. Program developers are the primary clients of this platform layer. Entire platform resources such as program testing, running, maintaining, and debugging are delivered by the platform directly from this layer. Hence, this form of services in the platform layer is termed platform as a service (PaaS). Classic examples of these services include Google App Engine and Microsoft Azure.

Software as a Service (SaaS)

Software as a service, defined as a provider who supplies remotely run software packages to consumers via the Internet on a utility-based pricing model. Analytical, interactive, transaction, and browsing facilities are included in the application layer. SaaS delivers several simple software programs and applications as well as customer interfaces to the end users. Thus, in the application layer, this type of service is called software as a service (SaaS). By using the client software or browser, the user can connect to services from providers via the Internet and pay fees according to the services consumed, in a pay-as-you-go model. Customer relationship management (CRM) from Salesforce is one of the early SaaS applications. Among other services, Google provides online office tools such as documentation, presentations, and spreadsheets, which are all part of SaaS.

Security as a Service (SecaaS)

The agility offered by the on-demand provisioning of computing resources and the ability to align information technology with business demands are valuable; however, clients are also very anxious about the security risks of cloud computing and the cost of direct control over the security of systems. Although vendors have attempted to satisfy this demand for security by offering security services in a cloud platform, the selection process is still completed. These issues have led to the restricted adoption of cloud-based security services, but the future looks bright for SecaaS, with Gartner predicting that cloud-based security service will be more than triple in many segments. To support both cloud customers and cloud providers, CSA has adopted a new research project to provide greater clarity in the area of SecaaS. It refers to the provision of security applications and services from the cloud to cloud-based infrastructure and software or from the cloud to the customers on premise systems. SecaaS will allow enterprises to make use of security services in new ways that would be more costly if provisioned locally.