When integrating Grafana with Instana, the plugin communicates using RESTful interactions over the HTTP protocol. IBM’s integration guide clearly explains: "The Instana DataSource Plugin for Grafana communicates with the Instana backend via HTTP-based REST APIs to query metrics and event data." This ensures secure TLS-encrypted data transport and allows compatibility with Grafana’s native data source management features. HTTP is chosen due to its simplicity, standardization, and suitability for web API integrations, allowing Grafana to query time-series data from Instana and automatically populate dashboards. The plugin retrieves metrics, trace-level summaries, and service health states over HTTP GET and POST requests. Other options such as gRPC are used only internally between microservices, SOP is not a standard communication protocol, and JDBC is limited to databases. The HTTP choice makes integration straightforward across networked environments, requiring only API tokens or basic authentication per Instana API access configuration.