Understanding service level agreements

A service level agreement (SLA) is a contract between a consumer and a service provider that specifies the expectations for the level of service with respect to availability, performance, and other measurable objectives. The SLA records a common understanding about services, priorities, responsibilities, guarantees, and warranties between the parties. The SLA can also specify levels of availability, serviceability, performance, operation, or other attributes of the service.

The SLA management process includes the following activities:
  • Defining the SLA by defining the policy to be enforced and associating it to the service, consumer, and policy subject.
  • Enforcing the SLA according to defined policies and metrics
  • Monitoring the SLA

Another contract that is used to define the availability of the service is the service level definition (SLD). The SLD details the capabilities of a provider to deliver a service in compliance with engagements that the provider supports.