APIs are all about measuring the value exchange that occurs between internal groups, with partners, and occasionally with the public when it makes sense. API management is where you start this conversation and has been used for a decade to measure, limit, and quantify the value being exchanged at the API level. Now that API management has been baked into the cloud, we are starting to see the approach being scaled to deliver at a marketplace level. With over ten years of experience with delivering, quantifying, metering, and billing at the API level, Amazon is the best example of this monetization approach in action, with two distinct ways of quantifying the business of APIs.
AWS Marketplace Metering Service — SaaS-style billing model that provides a consumption monetization model in which customers are charged only for the number of resources they use — the best-known cloud model.