Where can OSPF inter-area route summarization be configured?

OSPF inter-area route summarization can be configured specifically on Area Border Routers (ABRs) or Autonomous System Boundary Routers (ASBRs). ABRs are the routers that connect different OSPF areas to the backbone area (Area 0), which allows them to summarize routes from one area to another effectively. By summarizing routes at the ABR, it reduces the amount of routing information that must be processed and maintained, leading to a more efficient and scalable network design.

Since ASBRs connect OSPF to another routing protocol or to external networks, they can also be configured for route summarization, particularly for external routes. Thus, the summarization functionality is limited to these types of routers, as they have the role of handling multiple areas or routing protocols, making them the appropriate point for route aggregation.

While other routers in the OSPF domain can distribute OSPF routes, they do not have the capability to perform inter-area summarization as ABRs do. Therefore, the option stating that summarization is only configured on ABRs or ASBRs reflects the correct understanding of how OSPF manages inter-area routing efficiently.