An API management platform is a tool that acts as a proxy for customer requests to protect the back end of an online service from being brought down from too many queries. API programmers use API management platforms to ensure customers don't intentionally or unintentionally take down services by sending too many queries to the back-end server.
An API management platform limits the number of queries for each customer per second or per day. The platform does this by relaying requests between customers, consuming applications or partners and the API. This stops users from making more requests than the API can handle and creating what is effectively a DoS (denial of services) attack, whether intentional or not. A user will at most be able to bring down the API management platform, leaving the API still standing.
Generally API management platforms include analytics and usage reporting, API key and authorization management, live updated documentation, developer community management and billing and payment management. Popular API management platforms include Mashery, Apigee, 3 Scale and Layer 7.