The core functional areas can be viewed as configuration and management of hosts, virtual machines, and networks, as well as storage at an abstract level. The two core APIs that address these functional areas complement each other both in function and in design principles. Use the two APIs together to achieve complete functionality.

The vSphere Automation API applies REST design principles using JSON-based wire protocols, while the VIM API applies RPC principles using a SOAP protocol. In general, the Automation API offers a simpler design, while the VIM API offers better compatibility with older vSphere releases.