RIB & FIB

The routing and forwarding architecture in Cisco routers and multilayer switches used to be a centralized, cache-based system that combined what is called a control plane and a data plane. The control plane refers to the resources and technologies used to create and maintain the routing table. The data plane refers to those resources and technologies needed to actually move data from the ingress port to the egress port on the device. This centralized architecture has migrated so that the two planes can be separated to enhance scalability and availability in the routing environment.

The separation of routing and forwarding tasks has created the Routing Information Base (RIB) and the Forwarding Information Base (FIB). The RIB operates in software, and the control plane resources take the best routes from the RIB and place them in the FIB. The FIB resides in much faster hardware resources. The Cisco implementation of this enhanced routing and forwarding architecture is called Cisco Express Forwarding (CEF).