OSPF LSA Types
Type 5 LSA
- Called AS ELA (AS External Link Advertisements).
- Sent by ASBR’s.
- Advertises routes external to the OSPF AS, or the default route to the OSPF AS is reachable through them.
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Type 7 LSA
- Called NSSA (Not-So-Stubby-Area) external LSA.
- Help overcome limitations of an ASBR not being able to belong to a stub area.
- Only generated by an ASBR in a NSSA.
- The LSA propagates across the area to the ASBR.
- When it gets to the ABR, the ABR converts the Type 7 LSA to a Type 5 LSA and propagates it to the backbone.
- Advertises routes external to the OSPF AS.