Cloud interoperability is the ability of different cloud platforms, services, and control planes to work together through compatible APIs, identity systems, data formats, and governance rules. It matters because modern organizations rarely use a single provider for everything. They may split workloads across public cloud, private cloud, and hosted data centers, or move services between vendors as needs change.
In cyber security, interoperability can improve resilience and reduce vendor lock-in, but it also creates new trust boundaries. Defenders must keep logging, access control, encryption, and configuration policies consistent across environments. Attackers often exploit gaps between clouds, such as mismatched identities, weak API permissions, or incomplete monitoring during migration. Good interoperability therefore supports defense by making security controls portable, while poor interoperability increases the chance that a misconfiguration or stolen credential can spread across multiple systems.