SOA Patterns > Basics > SOA Project Fundamentals > Project and Lifecycle Stages > Service Usage and Monitoring
Service Usage and Monitoring
A service that has been deployed and is actively in use as part of one or more service compositions (or has been made available for usage by service consumers in general) is considered to be in the Service Usage and Monitoring stage. The on-going monitoring of the active service generates metrics that are necessary to measure service usage for evolutionary maintenance (such as scalability, reliability, etc.), as well as for business assessment reasons (such as when calculating cost of ownership and ROI).
Special considerations regarding this stage apply to cloud-based services, such as:
- the cloud service may be hosted by virtualized IT resources that are further hosted by physical IT resources shared by multiple cloud consumer organizations
- the cloud service usage may be monitored not only for performance, but also for billing purposes when its implementation is based on a per-usage fee license
- the elasticity of the cloud service may be configured to allow for limited or unlimited scalability, thereby increasing the range of behavior (and changing its usage thresholds) when compared to an on-premise implementation
This phase is often not documented separately, as it is not directly related to service delivery or projects responsible for delivering or altering services. It is noted in this book because while active and in use, a service can be subject to various governance considerations.