CCNP level

1. Lecture 10 - OSPF Part1 ,
Introduction to OSPF , Areas
and ABR
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2. What is OSPF
• IGP
• RFC 2328 by IETF
• Link-state advertisement (LSA) 30 Minutes & immediately
• Exam test on single Area
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3. Areas
• All areas connect to area0
• Same topology table within area
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4. OSPF Neighbor Adjacencies
• Hello protocol……….. Bidirectional communication
Router ID 32-bit number (higher IP address on an active interface)
Hello and Dead intervals*(4 x 10 Sec)
Neighbors
Area ID+
Router Priority (8 bit number to elect DR and BDR)
DR IP Address
BDR IP Address
Authentication Password
Stub Area Flag
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5. SPF Algorithm
Each router at the root of a tree
auto-cost reference-bandwidth ref-bw
Cost = reference bandwidth / interface bandwidth (in bps)
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6. Configuration
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7. Administrative Distance
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