- Type 1: Router LSA
- Type 2: Network LSA (Generated by DR)
- Type 3: Summary LSA (ABR Summary route)
- Type 4: Summary LSA (ASBR location)
- Type 5 External (ABSR Summary route)
Stubby Area: Blocks type 5 LSAs from entering. To enable: “area x stub”
Totally Stubby Area: Blocks type 3, 4 and 5 LSAs from entering (Cisco Proprietary although only ABR needs to be a Cisco device). To enable: “area x stub no-summary”
Not-So-Stubby Area (NSSA): Passes external routes via Type 7 LSAs; These convert back to Type 5 once they reach the backbone. To enable: “area x nssa”
Totally Not-So-Stubby Area (NSSA): Passes external routes via Type 7 LSAs; These convert back to Type 5 once they reach the backbone. Types 3, 4, and 5 are still filtered as per a Totally Stubby area. To enable: “area x nssa no-summary”
