This table contains information about routes to
destination networks from all BGP4 peers. Since
BGP4 can carry routes for multiple Network Layer
protocols, this table has the Address Family
Identifier(AFI) of the Network Layer protocol as the
first index. Further for a given AFI, routes carried
by BGP4 are distinguished based on Subsequent Address
Family Identifiers(SAFI). Hence that is used as the
second index. Conceptually there is a separate Loc-RIB
maintained by the BGP speaker for each combination of
AFI and SAFI supported by it.