A backend is a component that is not instrumented by an Splunk AppDynamics agent but one that participates in the processing of a business transaction instance. A backend may be a web server, database, message queue, or another type of service.

The agent recognizes calls to these services from instrumented code (called exit calls). If the service is not instrumented and cannot continue the transaction context of the call, the agent determines that the service is a backend component. The agent picks up the transaction context at the response at the backend and continues to follow the context of the transaction from there.

Performance information is available for the backend call. For detailed transaction analysis for the leg of a transaction processed by the backend, you need to instrument the database, web service, or other application.