Understanding SLAs

As an architect, once you’ve gathered and understood the non-functional requirements for a solution, you must design an architecture that balances the quality of service and the cost to implement and operate it. With your solution becoming a service or a product, you need to convey a message to your stakeholders, customers, and users claiming at what levels you will fulfill the non-functional requirements. When quantified, these become service-level objectives (SLOs) – hence, quality of service targets. And by conveying these SLOs to your stakeholders, customers, and users, you get into service-level agreements (SLAs).

If you are delivering an in-house solution, the SLAs become the service quality that needs to satisfy your stakeholders. On the other hand, if you supply your solution to customers, the SLAs become part of the official and legal engagement between you and your customers. In the cloud, as everything is a service, the SLAs critically...