Which LSA types can be summarized during OSPF inter-area route summarization?

In OSPF (Open Shortest Path First), route summarization is a technique used to reduce the size of the routing table by consolidating multiple networks into a single summarization address. This can streamline OSPF announcements and reduce the amount of routing information shared between routers.

Type 3 and Type 5 LSAs (Link-State Advertisements) are associated with inter-area and external routing, respectively, making them eligible for summarization.

Type 3 LSAs are generated by area border routers (ABRs) to communicate network information from one area to another. When summarization occurs, the ABR can combine multiple Type 3 LSAs into a single Type 3 LSA that represents a range of IP addresses. This is beneficial for reducing the information sent between OSPF areas, thus improving efficiency and reducing the processing load on routers.

Type 5 LSAs, on the other hand, are used to advertise external routes, such as networks learned from non-OSPF sources. These LSAs can also be summarized at the ASBR (Autonomous System Boundary Router) to condense multiple external routes into a single entry, further reducing complexity in the routing table.

In summary, Type 3 and Type 5 LSAs