What are Cloud Models?
Cloud models are there for enabling ever-present, convenient and on-demand network access to a shared pool of configurable computing resources. In the cloud, resources like Network, Server, Storage, Application, and Services can be rapidly made available or can be released with minimal management or service provider effort.
Let us take a look at the different types of Cloud Models:
1. On Premises
In this model, whole infrastructure sits at the premises of the organisation. There are no remote servers or services. The client has its own IT department team that looks after the setup, installation, maintenance & backups.
|In House: Highly preferable for companies that have high customization and security concerns and doesn’t want their data or applications to be available over public networks.||Non Cloud Model: As the services are not on cloud or over internet, they are not omnipresent and company may not be able to leverage its services from else where.|
|Lesser Long-Term Cost: Setup costs are to be incurred only once, there are no monthly fee or agreement costs.||High Initial Costs: As all the Infrastructure and Services needs to be owned by the company itself. The initial setup is considerably quite high.|
Microsoft Office, KMPlayer
2. Infrastructure as a Service (IAAS)
This model is a best fit to companies whose requirement is readily available infrastructure. The Enterprise can expect services such as Virtualization platform, Servers, Network model and Storage space from the Vendor. Enterprises have to just manage their application, data, run-time, middle-ware, and OS.
|Fast setup: As the whole hardware procurement and setup is handled by services providers, enterprises can sorely focus on its own application development.||Lesser Customization: IAAS service providers has its own standard infrastructure and networking model and there is hardly any scope for customization.|
|Pay as you scale: With IAAS services, you only pay for what you consume. Services are usually billed on an annual basis and also includes the maintenance costs.||Lesser Transparency in costs: Bills are not detailed enough and they usually highlight the availed services and other add-on service charges.|
Amazon Web Services(AWS), Microsoft Azure
3. Platform as a Service (PAAS)
This model goes one step further than IAAS and facilitates an environment wherein enterprises can directly develop or customize their application without worrying about anything else. Everything from the runtime environment to the server is provided by PAAS providers.
|Reduced setup costs: Enterprises have to shell out a nominal amount for their application setup. Everything else is taken care by the Paas providers.||Increased 3rd party dependency: The performance of your application depends on how vendor infrastructure is behaving during peak loads and crisis situations.|
|Increased Focus on Business: Since most of the layers are outsourced, there is more time & resource concentration on the business requirements.||Integration issues: There is lesser flexibility in terms of integration with the in-house applications developed by the enterprise.|
Salesforce Heroku, AWS Elastic Beanstalk
4. Software as a Service (SAAS)
Applications such as Office 365 and Google Apps are all built on the concept of SAAS model. Everything from Application to Server is provided by the SAAS vendor. This model is also called on-demand-software.
|Least upfront cost: There is no setup cost at all, services can be availed in the form of monthly of yearly subscriptions.||Connectivity constraints: In order to make use of SAAS services, you got to have all time network connectivity.|
|Easily accessible: SAAS services are developed in a way that they can be accessed anywhere from a handheld device or a computer over a network.||Limited Applications: Since SAAS is still in developing phase, there are limited no of services and applications.|
5. Business Process as a Service (BPAAS)
This model provisions horizontal and vertical business processes of a company on SAAS. It follows PaaS, IaaS and MaaS service models.
BPAAS provides with Architectural, Modeling, Technical, Design, Planning and Monitoring templates. This allows an enterprise to efficiently manage and deliver the expected output.