SaaS, PaaS, and IaaS


Software as a Service (SaaS) is an IT solution model in which users use a web browser to access software that resides in the cloud, along with the programs and user data. (“Cloud computing”)


  • was a pioneer of the SaaS model and it continues to deliver CRM(Customer Relationship Management) solutions to corporate clients across the globe. Other examples include-
  • Taleo SaaS
  • WebEx SaaS, and
  • Microsoft Office 365.


  • Lower costs of entry
  • Pay as you go
  • Risk transference
  • Scalability
  • Omnipresent access


  • Security may be a concern
  • Latency can become a problem
  • Total dependence on the Internet
  • Switching between SaaS vendors is difficult


Platform as a Service (PaaS) solutions provides a collection of hardware and software resources that developers can use to build and deploy applications with the cloud. (“Cloud computing”)


  • Microsoft Azure
  • Google App Engine
  • Apache Stratos


  • Lower total cost of ownership
  • Lower administrative overhead
  • More current system software
  • Increased business and IT alignment
  • Scalable solutions


  • Concerns about data security (“The Professionals Point”)
  • Integration challenges – porting legacy software to the cloud
  • Risk of breach of intellectual property
  • High dependency on PaaS – migrating is difficult


Infrastructure as a Service (IaaS) is a solution that offers computing hardware and any other IT resources to clients as a service. A SaaS provider may internally use an IaaS provider to host their services.


  • Amazon Web Services (AWS)
  • Cisco Metapod
  • Google Compute Engine (GCE)
  • Joyent


  • Elimination of an expensive and staff intensive data center
  • Ease of hardware scalability
  • Reduced hardware cost
  • Pay-as-you-go
  • Reduction of IT staff and storage space
  • Complete system admin and management risk transference


  • Complete dependence on IaaS provider (“Infrastructure-as-a-Service: Concepts, Advantages & Disadvantages”)
  • Transferring between IaaS providers is complex and rarely seamless


Jamsa, K. (2013). Cloud computing. New York: Jones & Bartlett learning.

Kumar, N. (n.d.). The Professionals Point. Retrieved September 16, 2017, from

Reed, R. (n.d.). Infrastructure-as-a-Service: Concepts, Advantages & Disadvantages. Retrieved September 16, 2017, from