When was YANG defined?

The correct answer is that YANG was defined in 2010. YANG, which stands for Yet Another Next Generation, is a data modeling language used to model configuration and state data manipulated by network management protocols such as NETCONF.

The formal introduction of YANG occurred in RFC 6020, published in October 2010. This document established YANG's syntax and semantics, setting the foundation for a standardized framework for modeling network devices and services. As a result, its definition in 2010 marked a significant advancement in the field of network management, promoting interoperability and ease of use across different network systems.

Understanding the timeline and context of YANG's development is crucial for grasping its importance in modern network management and automation practices.