why is it preferable to use OSPF over RIP
The biggest advantage of OSPF is that it is efficient; OSPF requires very little network overhead even in very large internetworks. The biggest disadvantage of OSPF is its complexity; OSPF requires prop er planning and is more difficult to configure and administer.
OSPF uses a Shortest Path First (SPF) algorithm to compute routes in the routing table. The SPF algorithm computes the shortest (least cost) path between the router and all the networks of the internetwork. SPF-calculated routes are always loop-free.
Instead of exchanging routing table entries like RIP routers, OSPF routers maintain a map of the internetwork that is updated after any change to the network topology. This map, called the link state
database, is synchronized between all the OSPF routers and is used to compute the routes in the routing table. Neighboring OSPF routers form an adjacency, which is a logical relationship between
routers to synchronize the link state database.
C hanges to internetwork topology are efficiently flooded across the entire internetwork to ensure that the link state database on each router is synchronized and accurate at all times. Upon receiving changes to the link state database, the routing table is recalculated.
OSPF using link cost information in determining routes instead of hop counts, overcoming the 16 hop limitation of RIP. 文章录入：csh 责任编辑：csh