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| 6.5 |  | Multiarea OSPF Operation |
| 6.5.6 |  | Updating the routing table |

After all routers receive the routing updates, they add them to their link-state databases and recalculate their routing tables. The order in which paths are calculated is as follows:

1. All routers first calculate the paths to destinations within their area and add these entries into the routing table. These are learned by way of Type 1 and Type 2 LSAs.
2. All routers then calculate the paths to the other areas within the internetwork. These paths are learned by way of interarea route entries, or Type 3 and Type 4 LSAs. If a router has an interarea route to a destination and an intra-area route to the same destination, the intra-area route is kept.
3. All routers, except those that are in any of the stub area types, then calculate the paths to the AS external, Type 5, destinations.

At this point, a router can reach any network within or outside the OSPF autonomous system.