Intent-Based Networking (IBN) is a closed-loop approach to network automation. The core principle involves translating high-level business or operational goals ("intent") into a required network configuration or "desired state." The IBN system then continuously monitors the network's "actual state" and compares it against this desired state. If any deviation or drift is detected, the system automatically takes corrective actions (remediation) to bring the network back into compliance with the original intent. This continuous validation and assurance loop is the fundamental characteristic of IBN.

A. This describes traditional, manual network management, which is reactive and labor-intensive. IBN is designed to automate and replace these manual processes with a proactive, goal-oriented system.

B. This describes a key characteristic of Software-Defined Networking (SDN), which is often a foundational technology for IBN. However, it only describes the mechanism of control, not the overarching IBN principle of assurance and validation against a desired state.

D. This describes a specific, advanced feature of a multi-domain service orchestrator, such as the Nokia Network Services Platform (NSP). While this capability can be part of an IBN implementation, it is a specific function, not the definition of the IBN concept itself.

1. Nokia Official Documentation: In the white paper "A practical guide to building intent-based networks," Nokia defines the process: "An IBN system continuously validates that the original business intent is being met. It does this by constantly monitoring the state of the network and comparing it to the desired state defined by the intent. If there is a mismatch, the IBN system takes corrective action to bring the network back into alignment with the intent." (Nokia White Paper, "A practical guide to building intent-based networks", 2020, Page 4, Section: "What is intent-based networking?").

2. Peer-Reviewed Publication (IETF): The Internet Engineering Task Force (IETF) draft on IBN concepts states, "An IBN system is a closed-loop control system... The main function of an IBN system is to bridge the gap between the intent and the network's current state... The IBN system is responsible for translating the intent into network control actions... and for continuously monitoring the network to ensure the intent is being met." (IETF Draft, "Intent-Based Networking - Concepts and Definitions", draft-irtf-nmrg-ibn-concepts-definitions-08, Section 2: "IBN Concepts", July 2021).