- Makes decisions about where traffic is sent
- Control plane packets are destined to or locally originated by the router itself
- The control plane functions include the system configuration, management, and exchange of routing table information
- The route controller exchanges the topology information with other routers and constructs a routing table based on a routing protocol, for example, RIP, OSPF or BGP
- Control plane packets are processed by the router to update the routing table information.
- It is the Signalling of the network
- Since the control functions are not performed on each arriving individual packet, they do not have a strict speed constraint and are less time-critical
- Also known as Forwarding Plane
- Forwards traffic to the next hop along the path to the selected destination network according to control plane logic
- Data plane packets go through the router
- The routers/switches use what the control plane built to dispose of incoming and outgoing frames and packets
The protocol or application itself doesn’t really determine whether the traffic is control, management, or data plane, but more importantly how the router processes it. Consider a 3 router topology with routers R1, R2 and R3. Lets say a Telnet session is established from R1 to R3. On both of these routers the packets need to be handled by the control/management plane. However from R2′s perspective this is just data plane traffic that is transiting between its links.
Control Plane => Learning what we will do
Our planning stage, which includes learning which paths the buses will take, is similar to the control plane in the network. We haven’t picked up people yet, nor have we dropped them off, but we do know the paths and stops due to our plan. The control plane is primarily about the learning of routes.
Data Plane => Actually moving the packets based on what we learned.
The data plane is the actual movement of the customers data packets over the transit path we learned in the control plane stage.
- High Performance Switches and Routers By H.Jonathan Chao