Cloud Service model – IaaS, PaaS, and SaaS 

IaaS, PaaS, and SaaS are three main model for cloud computing. Each model represents a different part of the cloud computing stack because they build on top of one another and build a business service model for the customers as per need.

These three name stand for the three main classifications of cloud computing which let you consider the level of control over on your information and types of services you need to provide.

• Infrastructure as a Service (IaaS)
• Platform as a Service (PaaS)
• Software as a Service (SaaS)

Infrastructure as a Service (IaaS):

IaaS cloud service model let you provide Infrastructure services on cloud Platform and facilitates outsourcing your services on the cloud platform.

It’s refer to outsource your IT Infrastructure to The cloud based virtual infrastructures virtualization technology like MS-Azure, AWS and Google Cloud.

IaaS model service allow you to outsource the components of infrastructure like Virtualization, Storage, Networking, and load balancers and many more to migrate on Cloud platform.IaaS clients have true control over their infrastructure than users of PaaS or SaaS services

With IaaS to deploy your applications to the Cloud, your responsibility to managed and install OS images and related application software, license, patch and update management.Including monitoring, backup jobs etc. Also responsivity to manage network components, Firewall, virtual server, load balancer etc. can access and manage via a dashboard or API (application programming interface).

Key Example of SaaS Solution -: 

• Amazon EC2
• Windows Azure
• Rackspace
• Google Compute Engine.

IaaS Features -:

• IaaS lets you rent IT infrastructure, users pay for IaaS on demand.
• IaaS Provides highest level of flexibility and management control over your IT resources.
• Choice of freedom and Flexibility.
• Saves enterprises the costs of buying and maintaining their own hardware.
• High availability of services, Device failure does not result in loss of data.

Platform as a Service (PaaS):

PaaS is a cloud service model that provides a platform and environment to allow developers to build applications and services over the internet simply via their web browser without worrying about setting up or managing infrastructure components.

PaaS provide quick, simple and flexible cloud platform solution where developer can quickly develop and operate web or mobile applications over the Internet without worrying about resource procurement, capacity planning, software maintenance, software patching etc and Provider gives you a fully functional OS with major platform software.

Key Example of SaaS Solution -:  

• WS Elastic Beanstalk
• Windows Azure
• Heroku, Force.com
• Google App Engine
• Apache Stratos, OpenShift

PaaS Features

• PaaS provides ready to use platform solution for Apps developers.
• PaaS is quick and flexible solution without worry about managing infrastructure.
• The Provider regularly patches your OS, updates platform features and updates hardware on demand
• Providers manage security, operating systems, server software and backups.
• PaaS provide the advantage to a software developers to build an application which they are planning to offer over the internet or software to be sold out of the box.

Software as a Service (SaaS):

SaaS is cloud service model potentially provide software application service to the customers that you need for your business. These applications managed and running on cloud provider’s infrastructure, making them available from various devices like browser or mobile.

SaaS Providers manage everything for the customer an allow customer enjoy the their respective  application without  worrying about resource procurement, capacity planning, software maintenance, patching, Load balancers and firewalls, Operating Systems and runtime environments like .NET and Java, the line of business applications and services.

Key Example of SaaS Solution -:

• O365 Office, SharePoint Server
• Lync Server Salesforce
• Cisco WebE
• Netflix, Web-Hosting
• CRM
• Citrix GoToMeeting
• Google Apps.

SaaS Features

• SaaS Model services provides users with software via a subscription model.
• The key benefit of SaaS is that it requires no up front investment in servers or software licensing.
• Data is secure in the cloud; Device failure does not result in loss of data.
• Computing resources can be scaled depending on needs.
• Application availability over the internet and web based.

Which is Right Choice -: IaaS, PaaS or SaaS?

Cloud computing is the practice of hosting and managing cloud solution on virtualization services.

It’s all about depend on requirement, manageability and skill. Before you choose IaaS, PaaS or SaaS, you should consider the trade-off between effort to Manage and Level of Control to take a conversant and fair decision.

In general, IaaS model provides the highest level of control among three (and may be more costly). The SaaS model takes least effort to manage (and may be less costly).