Routing Table
Routing Table Installed
The Routing Announcementsare installed as a routing table in the Network Operator Routers.
Routing announcementslet networks know where to send traffic. Here we see Transit Provider B announces reachability to all  destinations on the Internet. 
The Routing Announcementsare converted into a  Routing Table for the network.
With routing announcements in place, ISP A can send all traffic to its Transit Provider B, and Transit Provider B takes care of the rest.
Stop Animation