Cloud Service Models on AWS (IaaS, PaaS, SaaS)

Cloud services are commonly categorised into three models — Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Each model represents a different level of abstraction and determines what you manage versus what AWS manages for you.

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The Service Model Spectrum

Think of cloud service models as a spectrum from "you manage everything" to "you manage nothing":

  More Control                                    Less Control
  ◄──────────────────────────────────────────────────────────►

  On-Premises    IaaS          PaaS          SaaS
  ──────────    ──────        ──────        ──────
  You manage    You manage    You manage    You manage
  everything    OS upwards    app & data    nothing

                AWS manages   AWS manages   AWS manages
                hardware      hardware +    everything
                + network     OS + runtime

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The Responsibility Stack

To understand the models clearly, consider the full technology stack: