cisco培训07-Deploying OSPF.pptVIP

What Is OSPF? Has fast convergence Supports VLSM Processes updates efficiently Selects paths based on bandwidth Supports equal-cost multipath OSPF in IP Packets OSPF is a link-state routing protocol Relies on IP packets for delivery of routing information Uses protocol number 89 OSPF Terminology (cont.) OSPF Topologies Neighborship Neighborship (cont.) DR and BDR Electing the DR and BDR Hello packets exchanged via IP multicast Router with highest OSPF priority elected Exchange Process Discovering Routes Discovering Routes (cont.) Choosing Routes Maintaining Routing Information (cont.) Maintaining Routing Information (cont.) Point-to-Point Neighborship NBMA Topology Frame Relay Topologies DR Selection in NBMA Topology OSPF over NBMA TopologyModes of Operation NBMA Mode Neighborship Point-to-Multipoint Mode Neighborship Additional Cisco Neighborship Modes OSPF over NBMA Topology Summary Configuring OSPF on Internal Routers Configuring Optional Commands Router ID: Number by which the router is known to OSPF Default: The highest IP address on an active interface at the moment of OSPF process startup Can be overridden by a loopback interface: Highest IP address of any active loopback interface Configuring Optional Commands (cont.) Assigns a cost to an outgoing interface May be required for interoperability Uses default cost between Cisco devices Configuring OSPFover NBMA Topology Configuring OSPFover NBMA Topology (cont.) Configuring OSPF in NBMA Mode Configuring OSPF in Point-to-Multipoint Mode Configuring OSPF inBroadcast Mode Configuring OSPF in Point-to-Point Mode Verifying OSPF Operation Verifying OSPF Operation (cont.) Verifying OSPF Operation (cont.) show ip ospf interface show ip ospf neighbor—Multiaccess and Point-to-Point show ip ospf neighbor—NBMA Topology Broadcast Mode show ip ospf neighbor— NBMA Topology NBMA Mode show ip ospf database Issues with Maintaining a Large OSPF Network The Solution: OSPF Hierarchical Routing Consists of ar