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OSPF Link LSA (LSA Type 8) and Intra-Area-Prefix (LSA Type 9)


OSPFv3 brings a few changes in the LSA types. How packet OSPFv2 exchanges LSA in order to exchange self originated routes is discussed here. OSPFv2 exchanges IPv4 routes with the help of LSA 1 (Router LSA). This helps to propagate the route. In a broadcast segment it exchanges LSA 2 (Network LSA). 

I already discussed on different LSA of OSPF earlier expect LSA 8 and LSA 9. If you would like to have a look on that article below is the link.


For other OSPF articles, you can go through the below mentioned link


Let's have below topology, the IP address and the topology showing below is for the demo purposes and have no relevance with any of the enterprise networks.
Fig 1.1- OSPF LSA 8 and LSA 9
What does the router send when OSPF process needs to exchange IPv6 routes? In order to fulfil this requirement, two new LSAs are added which help exchange IPv6 routes 

LSAs that are responsible to carry IPv6 Routes:
  • LSA Type 8: Link LSA
  • Link Local scope: LSA is only flooded on the local link and is further used for the LINK-LSA
  • LSA Type 9: Intra-Area LSA
  • Area Scope: LSA is only flooded throughout a single OSPF area. Used for router-LSA, Network-LSA, inter-area-prefix-LSA, inter-area-router-LSA and intra-area-prefix-LSA
Example

Type-3 summary LSA have been renamed inter-area-prefix-LSA
Type-4 summary LSA have been renamed inter-area-router-LSA

A new LSA called the intra-area-prefix-LSA has been introduced. This LSA carries all IPv6 prefix information that in IPv4 is included in router LSA and network LSA.

Configurations

R1#sh running-config | s r o
!
router ospfv3 1
router-id 1.1.1.1
!
address-family ipv6 unicast
passive-interface Loopback0
exit-address-family
!

R1#
!
interface GigabitEthernet0/0
no ip address
duplex auto
speed auto
media-type rj45
ipv6 address 2001:ABCD::1/64
ospfv3 1 ipv6 area 1
end

!

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