Drag and Drop Question Drag and drop the types of management from the left onto the levels at which they are performed on the right. Answer:

Question

Exhibit

Answer Area

Explanation

This question tests the understanding of Software-Defined Networking (SDN) architectural layers, specifically distinguishing between management functions performed at the Controller level versus the Device level.

Approach. The correct interaction is to drag the management types to their corresponding operational levels based on SDN principles:

1. 'user and programmability interaction through the use of Northbound APIs' should be dragged to the 'Controller level'. Northbound APIs are interfaces used by the SDN controller to communicate with applications, orchestration systems, and policy engines above it. These APIs offer an abstract, high-level view of the network.

2. 'iterate over a list of devices' should be dragged to the 'Controller level'. An SDN controller maintains a global view of the network and is responsible for managing and orchestrating actions across multiple devices. Iterating over a list of devices to apply configurations, gather telemetry, or enforce policies is a central function of the controller.

3. 'user and programmability interaction through the use of lower level APIs' should be dragged to the 'Device level'. Lower-level APIs, often referred to as Southbound APIs in SDN (e.g., OpenFlow, NETCONF, RESTCONF), are used by the controller to communicate directly with individual network devices. Direct interaction with a device's specific management plane or operating system constitutes a lower-level interaction.

4. 'configure features with YANG models' should be dragged to the 'Device level'. YANG (Yet Another Next Generation) is a data modeling language used to model configuration and state data of network devices. Configuring features using YANG models, typically via protocols like NETCONF or RESTCONF, involves direct interaction with the device's configuration plane to modify its settings.

Common mistakes.

• common_mistake. A common mistake would be to confuse Northbound and Southbound (or 'lower level') API functions. Placing 'user and programmability interaction through the use of Northbound APIs' at the Device level is incorrect because devices do not expose Northbound APIs; those are the domain of the controller for higher-level applications. Similarly, putting 'configure features with YANG models' at the Controller level is wrong because YANG models are device-centric and used for direct device configuration, not for the controller's internal logic or its interactions with northbound applications. Misattributing the 'iterate over a list of devices' function to individual devices is also incorrect, as individual devices only know their own state and immediate connections, while the controller has the holistic network view needed for such iteration.

Concept tested. The core concept tested is the architectural understanding of Software-Defined Networking (SDN), specifically differentiating between the roles and responsibilities of the SDN controller and the network devices. This includes knowledge of Northbound and Southbound/lower-level APIs, data modeling with YANG, and the distribution of management and orchestration functions within an SDN environment.

No community discussion yet for this question.