The as-a-service label refers to the different service models cloud providers offer. There are three main as-a-service categories:
The National Institute of Standards and Technology (NIST) recognizes three standard cloud computing models of as-a-service: Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS), and Software-as-a-Service (SaaS).
In effect, each of these models offers a progressive level of abstraction – or management – by the cloud provider.
Each as-a-service model offers a unique set of benefits befitting your specific use case. Traditionally, organizations use a mix of these different models for different aspects of the business; for example, an organization may use the Salesforce platform (PaaS) and Google Docs (SaaS).
Definition: IaaS is the utilization of APIs to manage the lowest levels of network infrastructure, including networking, storage, servers, and virtualization.
Examples: Digital Ocean, Google Compute Engine, Microsoft Azure, Rackspace, and Amazon Web Services (AWS)
Common Use Cases: IaaS is the most flexible service model for cloud computing, so it is especially effective for startups and organizations looking for agile scaling. It is also preferred by businesses that seek greater control over their resources.
Definition: PaaS offers an even greater abstraction of cloud service, offering users the capability to build or deploy applications using tools (i.e. programming languages, libraries, services) without maintaining the underlying infrastructure. Users instead have control over the applications themselves.
Examples: Microsoft Azure, Salesforce, AWS Elastic Beanstalk, Heroku, Google App Engine (GAE), and OpenShift
Common Use Cases: PaaS is highly available and highly scalable, and it gives organizations the ability to build and create new services and solutions without the need for highly skilled developers focused on software maintenance. PaaS is preferred by IT in hybrid cloud environments.
Definition: SaaS enables users to use and access the cloud provider’s applications that are running on the provider’s infrastructure from thin client or program interfaces.
Examples: Microsoft O365, Google G-Suite, Dropbox, Cisco Webex, Concur, , Genesys, PayPal
Common Use Cases: SaaS is a comfortable service model for applications that are highly interoperable – used by multiple users internally and externally – and for short-term projects. SaaS models are preferred by small and medium-sized businesses that do not wish to invest heavily in IT maintenance.