Service Level Objective (SLO)

A Service Level Objective, or SLO, defines a specific target for the quality or reliability of an IT service. Common objectives relate to availability, latency, error rates, throughput or successful requests. Actual performance is measured using a Service Level Indicator, or SLI, and compared with the defined target. For example, an SLO may specify that a service should achieve 99.9 per cent availability over a defined period. SLOs are particularly relevant in Site Reliability Engineering, cloud computing and IT Service Management. They help IT teams objectively assess service quality and establish clear reliability targets. Unlike a Service Level Agreement, an SLO is often a technical or internal performance target and is not necessarily part of a contractual agreement.