Static routes, default routes

Routing: forwarding process from the source host to the target host.
Routing table: route to the destination router set maintained;
Routers make routing according to the routing table.
Forming the routing table:
① directly attached subnets: configure the IP address, port UP state, a direct route.
② not directly connected to the network ---- not directly connected network segment, requires a static routing or dynamic routing, the network will add to the routing table.
Static Routing: manually configured by the administrator, is one-way;
lack of flexibility.
The default route is a special static route, in particular to the network segment 0.0.0.0 0.0.0.0