Cloud computing isn't one-size-fits-all. There are three main models that offer different levels of control and management.
1Infrastructure as a Service (IaaS)
IaaS contains the basic building blocks for cloud IT and typically provides access to networking features, computers (virtual or on dedicated hardware), and data storage space. It provides you with the highest level of flexibility and management control over your IT resources.
2Platform as a Service (PaaS)
PaaS removes the need for organizations to manage the underlying infrastructure (usually hardware and operating systems) and allows you to focus on the deployment and management of your applications.
3Step-by-Step Breakdown
Before we dive into AWS, we need to understand the three main models of cloud service: IaaS, PaaS, and SaaS.
IaaS (Infrastructure as a Service) gives you the basic building blocks like servers and storage. You manage the OS and apps.
PaaS (Platform as a Service) removes the need for you to manage the underlying infrastructure. You only focus on your code.
Checkpoint: In which model do you focus only on your code and data, without worrying about the OS or server patching?
- →IaaS
- →PaaS
SaaS (Software as a Service) is a completed product that is run and managed by the service provider.
Understanding these models helps you choose the right tool for your project's needs.
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Accessibility (A11y)
1Managed Service Dashboards Should Not Assume Deep Technical Fluency
PaaS and SaaS tools are often chosen specifically to be usable by less specialized staff — any internal documentation or custom dashboard built around them should stay approachable, with clear labels rather than jargon-only interfaces.
2Vendor Lock-In Concerns Shouldn't Override Accessibility Requirements
When evaluating a SaaS tool for its convenience, still verify it meets accessibility standards (keyboard operability, screen reader support) before committing — a service that's easy to adopt but inaccessible to some team members creates a real long-term cost.
SEO Implications
- 1
PaaS Platforms Often Include Built-In CDN and Caching Benefits
Platforms like AWS Elastic Beanstalk or similar PaaS offerings frequently bundle load balancing and caching layers by default, which can improve page load speed metrics without any manual configuration — a modest indirect SEO benefit of choosing PaaS over raw IaaS.
- 2
SaaS Website Builders Can Limit Fine-Grained SEO Control
A fully managed SaaS website platform may restrict access to things like custom meta tags, structured data, or server-side rendering configuration — evaluate this tradeoff before choosing SaaS for a site where SEO customization matters.
Best Practices
Choose the Service Model Based on Where You Want to Spend Engineering Effort
IaaS demands the most operational effort (patching, scaling, networking) but gives full control; PaaS trades some control for not managing infrastructure; SaaS trades nearly all control for zero infrastructure management — pick based on what your team should actually be spending time on.
Don't Default to IaaS Just Because It's the Most Familiar Model
Teams experienced with traditional servers often reach for EC2 (IaaS) by habit even when a PaaS option like Elastic Beanstalk would eliminate real operational overhead for the same workload — evaluate the actual requirement, not just familiarity.
Frequent Bugs
A team spends significant engineering time on OS patching and server maintenance for a workload that doesn't need that level of control.
Reassess whether the workload could run on a PaaS offering (like Elastic Beanstalk) instead of raw IaaS (EC2) — if the team never needs to touch the underlying OS, PaaS eliminates that maintenance burden entirely.
A project locks into a SaaS tool early, then hits a wall when a needed customization isn't supported.
This is a common risk of SaaS's lower control — before committing, verify the SaaS platform's customization and export capabilities cover your actual long-term requirements, not just the initial use case.
Real-World Examples
Matching a Startup's Stack to the Right Service Models
An early-stage startup uses SaaS (Google Workspace) for internal collaboration, PaaS (Elastic Beanstalk) to deploy its application without managing servers, and IaaS (EC2) only for a specialized workload requiring custom kernel-level configuration.
// Collaboration: SaaS (Google Workspace)
// App hosting: PaaS (Elastic Beanstalk)
// Custom workload: IaaS (EC2)