OSPF LSA Types

 LSA types

1 - Router - LSA type 1

Sent by every router in the same area.
Does not leave the area.
Contains all the links the router has

2 - Network - LSA type 2

Sent by the DR
Does not leave the area
It contains all the routers in that broadcast domain.

3 - Summary LSA - LSA type 3

Sent by the ABR
It hides LSA1 and LSA2 and sends a summary to the other area.

4- ASBR Summary LSA - Type 4

Advertises the presence of the ASBR
This is the IP address of the ASBR in the OSPF domain.

5 - ASBR External LSA - LSA type 5

These are the redistributed routes from the ASBR
E1 - Most preferred, the metric will change
E2 - Less preferred, the metric is always 20
This LSA will not change in the OSPF domain, meaning the advertiser router is always kept and known even if it's multiple hops away.

6 - Group Membership LSA - LSA type 6

Designed for MOSPF and is not supported by Cisco. It will soon be retired.

7 - NSSA External - LSA type 7

Control the type 5 LSA to enter certain areas.

8 - External Attributes LDA-OSPFv2/Link local OSPFv3 - LDA type 8

For OSPFv2 used to transit BGP attributes through OSPF network while the BGP destinations are conveyed via LSA type 5.
This feature is not supported by most of the routers.
For OSPFv3 it's defined to carry IPv6 information through OSPF network.

9 - Opaque LSAs 9 - 10. Used for MPLS TE