How Does This Model Differ from a “Publisher-Subscriber” Model?

In the request-and-response model, the smart contract initiates the data fetch only when needed, making it suitable for one-off events or specific settlement times. In the publisher-subscriber model, the oracle continuously publishes data updates to the blockchain at fixed intervals or based on deviation thresholds.

This is more suitable for continuous, high-frequency data needs like perpetual futures funding rates or margin collateral price feeds.