Terminology:
RIB – Routing Information Base
FIB – Forwarding Information Base
RIB
This is a routing protocols database of routing prefixes that could potentially be installed in the routing table.
Derived from the control plane, it is not used for forwarding.
Every protocol such as OSPF, EIGRP, BGP has its own RIB and select their best candidates to try to install to global RIB so that it can then be selected for forwarding.
Is a selection of routing information learned via static definition or a dynamic routing protocol.
EX: show ip ospf databse show ip eigrp topology show ip bgp etc
FIB
The actual information that a routing/switching device uses to choose the interface that a given packet will use for egress.
Used for forwarding, information is derived from the RIB and from adjacency tables so that the packet can be rewritten with the correct encapsulation.
Is programmed by one or more RIB.
EX: show ip cef
