On which network plane is routing protocol traffic handled?

The control plane is the logical component of a network device responsible for making forwarding decisions. It handles all signaling and protocol traffic used to discover the network topology and build forwarding tables. This includes running routing protocols like OSPF, EIGRP, and BGP to exchange routing information with other devices. The control plane processes this information to create the routing table and then programs the data plane (e.g., by creating the FIB) to handle the actual packet forwarding.

A. The data plane is responsible for the high-speed forwarding of user traffic based on the instructions provided by the control plane.

B. The management plane is used for administrative access and device management, handling protocols like SSH, Telnet, and SNMP.

C. The authentication plane is not a standard, distinct plane in network architecture; authentication is a function often handled within the management or control planes.

1. Cisco Systems, Inc., "Control Plane Policing Implementation Guide, Cisco IOS XE Release 3S". Cisco Technology & Support Documentation. In the "Control Plane Policing Overview" section, it states, "The control plane is responsible for routing and for handling traffic that is directed to the router. This traffic includes routing protocol packets..."

2. Cisco Systems, Inc., "The Cisco ASR 9000 Series Aggregation Services Router Control Plane". Cisco White Paper. Section: "Control Plane and Data Plane", Paragraph 1. "The control plane’s main function is to provide the intelligence to run the network. It supports all signaling and routing protocols that are required to build and maintain the routing and forwarding tables..."

3. Feamster, N., Rexford, J., & Zegura, E. (2014). "The Road to SDN: An Intellectual History of Programmable Networks". ACM SIGCOMM Computer Communication Review, 44(2), 87–98. https://doi.org/10.1145/2602204.2602219. In Section 2, "The Data, Control, and Management Planes," the paper defines the control plane as the component that "computes the forwarding table used by the data plane," explicitly including routing protocols in its function.