What is used by vManage to interact with Cisco SD-WAN devices in the fabric?

IPsec is a security protocol used for creating secure tunnels over IP networks, primarily for data plane encryption, not an API for vManage interaction.

vManage exposes a northbound API (RESTful API) that allows external orchestration systems and automation tools to integrate with and manage the Cisco SD-WAN fabric, facilitating programmatic control and data retrieval.

RESTCONF is a protocol for accessing NETCONF-like data over HTTP, which vManage might use internally or expose as part of an API, but 'northbound API' is the broader category for external interaction.

Southbound APIs are used by vManage to communicate with and control the underlying network devices (vEdge/cEdge routers, vSmart, vBond controllers) within the SD-WAN fabric, rather than for external interaction with vManage itself.