Types of OSPF Routers

• Transit (internal) routers:

• • Routers inside of an area
  • Contain only one routing table

• Area border routers (ABRs):

• • Routers between multiple areas
  • Contain one routing table per area

• Autonomous system boundary routers (ASBRs):

• • Routers that exchange routes with a different autonomous system (typically using an EGP)
  • Contain one routing table per OSPF area and one routing table for the protocol used by the other AS.