Exam 300-420 topic 1 question 74 discussion

Definitely A https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-sda-design-guide.html#ControlPlane Answer B describes the Edge node purpose, not Control plane node!

The control plane node’s database tracks all endpoints in the fabric site and associates the endpoints to fabric nodes, decoupling the endpoint IP address or MAC address from the location (closest router) in the network.

The correct answer is B. The purpose of a control plane node in a Cisco SD-Access network fabric is to detect endpoints in the fabric and inform the host tracking database of EID-to-fabric-edge node bindings. The control plane nodes in the fabric keep track of the location of endpoints and communicate that information to the other nodes in the network to ensure that traffic is delivered to the correct destination. They are also responsible for forwarding policy information to the edge nodes to enforce access control and segmentation policies.

A is the correct one

The right answer is A

Answer A is correct. See: https://www.cisco.com/c/en/us/td/docs/solutions/CVD/Campus/cisco-sda-design-guide.html Endpoint registration—Each edge node has a LISP control-plane session to all control plane nodes. After an endpoint is detected by the edge node, it is added to a local database called the EID-table. Once the host is added to this local database, the edge node also issues a LISP map-register message to inform the control plane node of the endpoint so the central HTDB is updated.

A is the answer

A is correct

A is correct. Each edge node has a LISP control-plane session to all control plane nodes. After an endpoint is detected by the edge node, it is added to a local database called the EID-table. Once the host is added to this local database, the edge node also issues a LISP map-register message to inform the control plane node of the endpoint so the central HTDB is updated.

I think this is A. Control Plane node wouldnt detect the endpoints - that would be the edge node.