Question: What are the two primary reasons for using OSPF or IS-IS routing protocols for SD-Access underlay deployments? Need Assignment Help? (Choose two.) Link-state routing protocols converge much faster than distance vector routing protocols. Link-state protocols advertise the entire routing table in the routing updates. IS-IS and OSPF are Cisco proprietary distance vector routing protocols. Distance vector routing protocols converge much faster than link-state routing protocols. IS-IS and OSPF are open standard protocols.