cisco ccna 200 301 exam

cisco ccna 200 301 exam.The topology table is similar to the OSPF database and contains all the destination networks and paths that the router is informed about, basically merged from the routing tables of the neighboring routers. There is a topology table for each protocol being routedSuccessor routes Best path to the destination network in the topology tableFeasible successor routes Best alternate path to the destination network in the topology table; for a given destination, there may be multiple feasible successor routesRouting table Contains all the successor routes in the topology table; there is a routing table for each protocol being routedNotification distance Distance of routes notified by neighboring routers (metric)Feasible distance Distance calculated by the router for a particular route: distance advertised by the neighboring router plus the metric value of the router interfaceExam Points Be sure to familiarize yourself with the terms listed in Table 20.1.When selecting the best path to the destination network, EIGRP uses a less complex algorithm than OSPF and uses less CPU, but it does have more overhead than distance vectoring protocols such as RIPv2. EIGRP routers store topology information in a topology table; the topology table contains routes advertised by neighbors and the advertised distance (distance advertised by neighbors) and feasible distance (distance to the target network from the current router) for those routes. o A successor route is the path with the smallest metric (feasible distance) in the topology table one-by-one than any other alternative path to the same target network. o A successor route is the path with the smallest metric (feasible distance) in the topology table. A feasible successor route is a valid alternate route to a successor route.Not any route can be a feasible successor route. For a route in the topology table to be a feasible successor route, its announcement distance must be less than the feasible distance of the feasible route. If a route in the routing table fails and there is a feasible successor route in the topology table, the EIGRP router enters a reactive state - immediately adding the feasible successor route in the topology table to the routing table, and convergence is almost instantaneous. If there are no feasible successor routes in the topology table, the EIGRP router enters the active state: generates a query packet and sends it to a neighbor that advertises an alternative path.Exam Essentials Successor routes are stored in the IP routing table and the EIGRP topology table; feasible successor routes are valid alternate routes that can be used in the event that a successor route fails.