フリー問題

問題文

In an OSPF deployment on a firewall, what does dividing the network into areas accomplish?

選択肢

1. It limits how far the detailed link state information is flooded, so a change inside one area does not force every router in the network to recompute.
2. It creates a separate routing table for each area, so a lookup consults only the table that belongs to the incoming interface.
3. It assigns a separate administrative distance to each area so that the firewall can prefer routes from one part of the network over another when the same prefix is learned from two directions.
4. It encrypts the link state advertisements exchanged inside the area, which makes an area the smallest unit for which authentication can be set.