01. OSPF Foundations & Initialization

• Introduction to OSPF: Protocol versions and core characteristics
• Interface Types: Point-to-Point, Broadcast, Non-Broadcast, and Point-to-Multipoint
• Neighbor States: Down, Init, Two-Way, ExStart, Exchange, Loading, and Full
• Packet Types: Hello, DBD, LSR, LSU, and LSAck
• DR/BDR Election: Designated and Backup Designated Router roles and priorities

02. Intra-Area Operations & Metrics

• Network Convergence: LSA Flooding and SPF tree calculation
• OSPF Metrics: Understanding Cost and Reference Bandwidth
• Metric Manipulation: Altering interface costs and default metrics
• LSA Types Overview: Understanding the purpose of Type 1 and Type 2 LSAs

03. Multi-Area Design & Router Roles

• The Backbone: Function and requirements of Area 0
• Specialized Area Types: Standard, Stub, Totally Stubby, and Not-So-Stubby (NSSA)
• Router Designations: Internal, Area Border Router (ABR), and Autonomous System Boundary Router (ASBR)

04. Advanced LSA Propagation & Reachability

• Deep Dive into LSA Types: Type 3 (Summary), Type 4 (ASBR Summary), Type 5 (External), and Type 7 (NSSA)
• External Reachability: Injecting routes and understanding E1 vs. E2 metrics
• Redistribution: Managing routing information between OSPF and other protocols

05. Optimization, Security & Summarization

• Route Summarization: Inter-area (ABR) and External (ASBR) summary techniques
• OSPF Authentication: Plaintext vs. MD5/SHA secure adjacency
• Best Practices: Passive interfaces and stub area optimization