The internet backbones run almost entirely BGP4 which is a very compute
intensive high memory requirement routing protocol which is aware of the
entire network. It also includes policy based routing in that you can
talk in terms of provider networks and rules between them and say things
like
"route all mcinet traffic via x"
"advertise our route to sprint except to milnet"
BGP4 is overkill for people with one net connection. OSPF and RIP sit
under that (as can static routing) and funnel the data to the nearest BGP4
aware target.
Alan