Lab: Distributing Level-2 IS-IS Routes into Level-1 Areas
OSPF and IS-IS differ in inter-area route handling, with OSPF copying intra-area routes into the backbone, while IS-IS uses level-1 areas like totally stubby OSPF areas without copying level-2 routes.
MAIN POINTS
- OSPF copies non-backbone intra-area routes into the backbone area.
- After the backbone SPF run, OSPF routes are copied into other areas.
- IS-IS does not copy level-2 routes into level-1 areas.
- Level-1 IS-IS areas behave like totally stubby OSPF areas.
TAKEAWAYS
- OSPF and IS-IS handle inter-area routes differently.
- OSPF uses a backbone area for route copying.
- IS-IS relies on the ATT bit for default route generation.
- Understanding these differences is crucial for network design.