SaaS, PaaS or IaaS: start with responsibilities

SaaS: use the software

Software as a service gives you an application delivered as a service. It can suit a business that wants a particular workflow without operating the underlying application infrastructure. Your team still needs to manage its users, configuration, information and the way the software fits its work.

Ask about access controls, integration, data export, retention, support and what happens if you stop using the service. A convenient interface does not remove the need to understand these choices.

PaaS: focus on the application

Platform as a service provides an environment for deploying applications while the provider handles specified underlying platform and infrastructure responsibilities. It can reduce some operational work, but your application, dependencies, data and access choices still matter.

Check supported application requirements, deployment and rollback, capacity limits, observability, backups and portability. The platform should fit the workload you actually have.

IaaS: take more infrastructure control

Infrastructure as a service provides computing resources such as processing, storage and networking. It gives you more control over the systems you deploy—and more responsibility for operating systems, applications and their configuration.

Clarify who patches, monitors, backs up, restores and responds to incidents. A managed-service agreement may cover some of that work, but those responsibilities need to be explicit rather than assumed.

Compare the complete operating picture

A single organisation may use all three models for different workloads. Write down what each workload needs and compare the service on that basis. Price is only one part of a useful decision.

• Purpose: users, workflow, integrations and locations.
• Control: identity, configuration, deployment and data portability.
• Continuity: acceptable interruption and information loss, with a tested recovery process.
• Cost: compute, storage, retained backups, data movement, licences and support.
• People: the skills and time available to operate the service.

Prepare a brief before choosing a package

Describe what must run, what already exists, what information it holds and the constraints you need to respect. Include expected changes in demand. That brief makes it easier to discuss a suitable platform and an accountable operating arrangement.

Keep exploring