Open Shortest Path First
Open Shortest Path First (OSPF) is a link-state routing protocol that was created by the IETF in 1988. It is capable
of quickly detecting topological changes within the autonomous system and establishing loop-free routes2
with the
least amount of extra communication required for negotiating topology changes between peering routers.
Area - The OSPF area keyword identifies an OSPF area.
Router ID - uniquely identifies a router in an OSPF area.
Cost Value - OSPF uses costs as route metrics. Each OSPF-enabled interface maintains a cost value.
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ROUTES ARE NOT EXCHANGED BY OSPF ROUTERS; ONLY CONNECTION STATUS INFORMATION IS.
FOR OSPF TO CALCULATE TOPOLOGY AND ROUTES, LINK STATUS INFORMATION IS ESSENTIAL.
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A NETWORK'S LINK STATUS DATA IS GATHERED BY AN OSPF ROUTER AND STORED IN THE LSDB.
ROUTERS CAN DETERMINE LOOP-FREE PATHWAYS AND ARE AWARE OF THE INTRA-AREA
NETWORK TOPOLOGY.
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THE OSPF NEIGHBOR TABLE DESCRIBES THE STATUS OF THE NEIGHBOR
RELATIONSHIP BETWEEN OSPF ROUTERS.
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AN OSPF ROUTER COLLECTS LINK STATUS INFORMATION ON A
NETWORK AND STORES THE INFORMATION IN THE LSDB. ROUTERS ARE
AWARE OF THE INTRA-AREA NETWORK TOPOLOGY AND ARE ABLE TO
CALCULATE LOOP FREE PATHS.
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EXECUTING THE COMMAND TO QUERY THE LSDB.
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[R1] DISPLAY OSPF PEER
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OSPF ROUTING TABLE CONTAINS INFORMATION, SUCH AS
THE DESTINATION IP ADDRESS, COST, AND NEXT-HOP IP
ADDRESS, WHICH GUIDES PACKET FORWARDING. [R1]
DISPLAY OSPF ROUTING