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RFC · RoutingStandard explained

RFC 2328: OSPFv2: Link-state routing in IPv4 networks

Summary

RFC 2328 defines OSPFv2 as a dynamic interior routing protocol for hierarchical IPv4 networks. A shared view of the topology enables fast, decentralised decisions. Hierarchy becomes necessary as soon as a complete view gets too expensive.

Ideas

  • Routers distribute the state of their links.
  • Every router calculates shortest paths from the same topology database.
  • Areas limit flooding and computation effort.

Facts

  • RFC 2328 replaces RFC 2178.

Remarks

  • RFC 2328 has the status “Internet Standard”; current errata and successor documents should also be checked.

Recommendations

  • Authenticate adjacencies and filter unexpected participants.
  • Plan areas along a stable topology instead of org charts.

References

Read the RFC at the RFC Editor

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