How to read the OSPF Database

Lessons Discussion
16

Hello Rene,

I have three questions:

  1. Can you please explain what vertex means? maybe an example will help me understand the concept.

  2. When you start analyzing R2 and it LSDB, how you determine that R2 has two networks with the same subnet. I can see R1-R2 subnet is 10.0.12.0/24 and LAN R2 is 10.12.0/24, as well.

I got confused in this part:

Link connected to: a Stub Network
(Link ID) Network/subnet number: 10.0.12.0
(Link Data) Network Mask: 255.255.255.0
Number of TOS metrics: 0
TOS 0 Metrics: 10

I think the above entry in 2.2.2.2 is referring to the R1-R2 edge.

  1. Same thing, when you are describing the LSDB Optimizations:

Under R3#show ip ospf database router self-originate, why you count 6 links, when 10.0.35.0/24 is the P2P between R3 - R5, but in the diagram you show as another link?

Thanks,

Jose