CCNP ROUTE - Opaque LSAs

Type 9, 10, 11 (Opaque LSAs) may be used for distributing application-specific information through an OSPF domain.

  • Type 9 LSAs are not flooded beyond the local network or subnetworks.
    • A link-local "opaque" LSA (defined by RFC2370) in OSPFv2 and the Intra-Area-Prefix LSA in OSPFv3. It is the OSPFv3 LSA that contains prefixes for stub and transit networks in the link-state ID.
  • Type 10 LSAs are not flooded beyond the borders of their associated area.
    • An area-local "opaque" LSA (defined by RFC2370). Opaque LSAs contain information which should be flooded by other routers even if the router is not able to understand the extended information itself. Typically type 10 LSAs are used for traffic engineering extensions to OSPF, flooding extra information about links beyond just their metric, such as link bandwidth and color.
  • Type 11 LSAs are not flooded through the AS.
    • An AS "opaque" LSA defined by RFC 5250, which is flooded everywhere except stub areas. This is the opaque equivalent of the type 5 external LSA.

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