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Link State Advertisements Router-LSA Links: The choice of which neighbors to include in the router-LSA is flexible, subject to only two requirements: A router MUST include all Full neighbors in its router-LSA. A router MUST NOT include any non-routable neighbors in its router-LSA. Four options for the router-LSA, depending on LSAFullness: Minimum LSAs: Include only fully adjacent neighbors. Full LSAs: Include all routable neighbors. MDR Full LSAs: Only (Backup) MDRs originate Full LSAs, other routers originate Minimum LSAs. Min-Cost LSAs: Include the minimum set of neighbors to provide a 2-hop path between each pair of neighbors, based on the neighbors’ LSAs. Provides min-hop routing if all link costs are equal. Provides min-cost routing under certain assumptions. The four LSA options are interoperable with each other, since they all satisfy the above two requirements. |