Thursday, December 17, 2009
CCNP Basic OSPF Theory
Today I started my studying on OSPF in the CCNP BSCI Study Guide book. It was mainly just review of LSDB's, LSA's, and the packets that are used to get OSPF up and running. While most of it was CCNA review material the book did go in-depth regarding the packet types and their function. It also displayed interesting diagrams and analogies to help understand how OSPF builds its Link-State Database (LSDB). You can think of LSDB as a map you're looking at in the mall, and the mall it self being the OSPF network. There are multiple maps placed throughout the mall with the same information regarding where every store is located just the same as each router has the same LSDB in an OSPF network . The only difference between the maps in the mall is the "you are here" dot. The dot determines where you are in the mall and the best path to get to every store within that mall. OSPF functions very similar to this, each router uses the LSDB and it's location in the network to determine the best path to get to every other router within the OSPF network!
Tonight I will be finishing up a few more pages regarding OSPF theory and then tomorrow I hope to jump right into configurations, the fun stuff. The pic I added today shows the current topology of the entire global network, pretty wild stuff!