Which capability do EIGRP and OSPF share?

EIGRP and OSPF both support MD5 authentication for routing updates, enhancing security by ensuring that routing information comes from trusted sources. This prevents unauthorized routers from injecting false routing information. Unequal-cost load balancing is a feature specific to EIGRP; OSPF only performs equal-cost load balancing. Autosummarization is primarily an EIGRP feature (though OSPF can summarize routes, it's not "autosummarization" in the same sense and is typically done manually at ABRs/ASBRs). While both are interior gateway protocols, their underlying algorithms (EIGRP uses DUAL, OSPF uses Dijkstra's SPF) lead to different operational characteristics, including variations in CPU usage, scalability, and convergence times depending on network design and size. Therefore, stating they have similar performance metrics is inaccurate.