Final answer:
In Azure API Management (APIM), each subscription has two keys: a primary and a secondary key, allowing secure access to API services and enabling key rotation without service interruption.
Step-by-step explanation:
Each subscription in Azure API Management (APIM) contains two keys: a primary key and a secondary key. These keys are used for authenticating API calls and managing access to the API services. Azure API Management provides these two separate keys to allow for flexible key rotation strategies without interrupting service continuity. If a key needs to be regenerated, either due to security reasons or regular maintenance cycles, having both a primary and a secondary key ensures that clients can switch to the unused key while the other is being reset. This system enhances security and minimizes potential downtime for consumers of the API.