Common LSA types defined by OSPF of S series switches

Question: What are the common LSAs used in OSPF of S series switches? Why Type 6 LSAs do not exist?

Answer: On S series switches supporting OSPF, OSPF uses the following types of LSAs:
Type 1 LSA: router LSA
Type 2 LSA: network LSA
Type 3 LSA: summary LSA
Type 4 LSA: ASBR-summary LSA
Type 5 LSA: AS-external-LSA
Type 7 LSA: NSSA AS-external-LSA
OSPF packets were encoded based on Type-Length-Value (TLV). To enable other OSPF functions, you need to use LSAs of other types.

Type 6 LSAs, indicating group-membership-LSAs, are used to identify multicast group members in Multicast Open Shortest Path First (MOSPF). Switches do not support Type 6 LSAs.

Type 8 LSAs, indicating external-attributes-LSAs, are used to import BGP routes into OSPF processes for inter-operations and reserve information about BGP routes such as AS-Path. Switches do not support Type 8 LSAs.

The Opaque LSA type is defined by RFC 2370 and can use the TLV structure. Applications such as OSPF Traffic Engineering (TE) are implemented by the Opaque LSA.

The Type 9 LSA is the Opaque LSA flooding on a link.
The Type 10 LSA is the Opaque LSA flooding within an area.
The Type 11 LSA is the Opaque LSA flooding within an AS.

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