Even though my next post was going to be about some enhancements to STP, I found this little nugget about OSPF behavior, that I thought I would share with everyone. As we know OSPF, when crossing an area boundary, the ABR (Area Border Router), will gather type 1 (router and its links) and type 2 (network information provided by the DR on a transit network) and form a type 3 LSA, which is basically a boiled down version of the two other types of LSA’s.