Characteristics of IaaS, PaaS and SaaS

IaaS Characteristics

  • Scale
  • Converged network and IT capacity pool
  • Self-service and on-demand capacity
  • High reliability and resilience

IaaS key Benefits

  • Usage is metered and price on the basis of units (or instances) consumed
  • The ability to scale up and down of infrastructure service based on actual usage.
  • Reduced cost of ownership
  • Reduced energy and cooling costs.

PaaS Key Characteristics

  • Support multiple languages and frameworks
  • Multiple hosted environments
  • Flexibility
  • Allow choice and reduce “lock-in”
  • Ability to “Auto-scale”

PaaS Key Benefits

  • The operating system can be changed and upgraded frequently including associated features and systems services
  • Globally distributed development teams are able to work together on software development projects within the same environment
  • Service is available and can be obtained from diverse sources that cross international boundaries.
  • Upfront and recurring or ongoing costs can be significantly reduced.

Software as a Service (SaaS)


  • SaaS is a distributed model where the software application is hosted by a vendor or cloud service provider and made available to customers over network resources
  • Two delivery models:
  1. “Hosted Application Management” (hosted AM)
  2. “Software on Demand”


  • Clients are able to access their application and data from anywhere at any time
  • Overall reduction of costs
  • Application and Software Licensing
  • Reduced Support Costs
  • Back End Systems and Capabilities

SaaS Benefits

  • Ease of use and limited/minimal administration
  • Automatic updates and patch management
  • Standardization and compatibility
  • Global accessibility