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Which LSA type is advertised by all OSPF routers?
Type 5 LSA
1.0/24 is to be advertised in OSPF areas. This is the responsibility of ASBR to advertise other routing protocol routes into OSPF areas therefore R4 will now create a Type 5 LSA to advertise these route to all other OSPF areas.
What type of router generates a router link LSA?
This is why the ABR will generate a summary ASBR LSA which will include the router ID of the ASBR in the link-state ID field. Type 5 – External LSA: also known as autonomous system external LSA: The external LSAs are generated by the ASBR….OSPF LSA Types Explained.
| Link Type | Description | Link ID |
|---|---|---|
| 4 | Virtual Link | Neighbor router ID |
Who generates Type 4 LSA?
ABR
This type-4 LSA is generated by an ABR, providing information to reach an ASBR. The LSA itself includes the router ID of the ASBR, the advertising router ID (which is the ABR) and a network mask of all 0s. Essentially what the ABR is saying is this – to get to the ASBR, you can go through me.
What type of router generates a Type 5 LSA?
Autonomous System Boundary Router
An OSPF type 5 LSA is originated by an Autonomous System Boundary Router (ASBR) and flooded within the OSPF area. These routes are generated by means of redistribution into OSPF from other protocols or by the redistribution of connected or static routes.
What is Type 3 LSA OSPF?
The Summary (Type 3) LSA is used for advertising prefixes learned from the Type 1 and Type 2 LSAs into a different area. The Area Border Router (ABR) is the OSPF device that separates areas and it is this device that advertises the Type 3 LSA. Examine the OSPF topology shown in Figure 1 below.
What are the different types of router LSA?
Let me summarize the LSA types for you: Type 1 – Router LSA: The Router LSA is generated by each router for each area it is located. In the link-state ID you will find the originating router’s ID. Type 2 – Network LSA: Network LSAs are generated by the DR. The link-state ID will be the interface IP address of the DR.
Do you need DR / BDR for broadcast network?
The broadcast and non-broadcast network types require a DR/BDR. If this is the case you will see these network LSAs being generated by the DR. In this LSA we will find all the routers that are connected to the multi-access network, the DR and of course the prefix and subnet mask.
Is there such a thing as a summary LSA in OSPF?
The name “summary” LSA is very misleading. By default OSPF is not going to summarize anything for you. There is however a command that let you summarize inter-area routes. Take a look at my OSPF summarization lesson if you are interested.
Why does the ABR generate summary ASBR LSA?
This is why the ABR will generate a summary ASBR LSA which will include the router ID of the ASBR in the link-state ID field. Type 5 – External LSA: also known as autonomous system external LSA: The external LSAs are generated by the ASBR.