Ερώτηση 1&2:A destination in the topology table can be marked either as Passive or Active. A Passive state is a state when the router has identified the successor(s) for the destination. The destination changes to Active state when current successor no longer satisfies the Feasibility Condition and there are no feasible successors identified for that destination (i.e. no backup routes are available). The destination changes back from Active to Passive when the router received replies to all queries it has sent to its neighbors. Notice that if a successor stops satisfying the Feasibility Condition but there is at least one feasible successor available, the router will promote a feasible successor with the lowest total distance (the distance as reported by the feasible successor plus the cost of the link to this neighbor) to a new successor and the destination remains in the Passive state.In EIGRP the passive-interface command stops sending outgoing hello packets, hence the router can not form any neighbor relationship via the passive interface. This behavior stops both outgoing and incoming routing updates.In OSPF the passive-interface has a similar behavior to EIGRP. The command suppresses hello packets and hence neighbor relationships.
Ερώτηση 3:Multiplier define the range of metric values that the EIGRP process allow for load balancing.
Ερώτηση 4:Virtual link είναι μια λογική σύνδεση για να δημιουργηθεί εικονική γειτνίαση μεταξύ των δύο περιοχών που χρησιμοποιούν το least cost path
Ερώτηση 5:Υπάρχει ένας και μόνο successor και κανένας feasible successor.
Ερώτηση 6:EIGRP is a distance vector routing protocol. It only knows about distances/routes from what its’ neighbors tell it. The only way EIGRP can trust that another router’s route is not back through itself, is to makesure the other router’s distance is equal to or less than its own distanceto that network
Ερώτηση 7:OSPF areas are designed to keep issues like flappinglinks within an area. SPF is
not recalculated if the topology change is inanother area. The interesting thing is that OSPF distributes inter-area (betweenareas) topology information using a distance-vector method. OSPF uses link-state principles only within an area. ABRs do not announce topologicalinformation between areas, instead, only routing information is injected intoother areas. ABRs relay routing information between areas via distance vector technique similar to RIP or IGRP. This is why show ip ospf does not
show achange in the number of times SPF has been executed when the topologychange is in another area
Ερώτηση 8: Shortest path algorithm ή Dijkstra
Ερώτηση 9:The main difference is in the way they find out the best path to a remote network; Distance-Vector protocols use hops, while Link-state routing protocols use bandwidth. Moreover, Link-state protocols have a more complicated way they work, as they have a complete “view” of all the internetworking, while the DV not.
Ερώτηση 10: Metric Cost=10^8/ Bandwidth
Ερώτηση 11: 64
Ερώτηση 12: 1
Ερώτηση 13: 1765
Ερώτηση 14: όλοι οι router που ανήκουν σε αυτήν την περιοχή έχουν το ίδιο LSD
Ερώτηση 15:
-Decrease routing overhead.
-Speed up convergence.
-Confine network instability to single areas of the network.
Ερώτηση 16:OSPF would be chosen in case we had a discontiguous network, because OSPF does not auto-summarize at classful boundries as RIPv2 does.