Which three YANG model types are supported by Cisco IOS XR?

The selection of OpenConfig as a supported YANG model type in Cisco IOS XR highlights the platform's commitment to industry standards and interoperability. OpenConfig is a vendor-neutral initiative that provides a set of YANG data models aimed at supporting network automation across various platforms, making it very relevant for modern network programmability and automation strategies.

Cisco IOS XR also supports Cisco-specific YANG models, which provide detailed control over Cisco's networking features and capabilities. These models are designed to leverage the proprietary functionalities of Cisco equipment while ensuring programmability.

In addition, the IETF YANG models are crucial as they represent standardized models widely used across various network devices and are fundamental for enabling consistent network device management.

OpenDaylight is not a YANG model type in the same context; rather, it is a platform for network programmability that leverages YANG models but is not itself supported as a YANG model type within Cisco IOS XR. Understanding the distinctions and purposes of these models is integral to leveraging Cisco IOS XR for network automation and management effectively.