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How are OSPF route attributes propagates across the MPLS VPN backbone?

How are OSPF route attributes propagates across the MPLS VPN backbone? (Choose two)

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A.
OSPF priority is propagated in the Experimental Bits.

B.
OSPF cost or external metric is propagated in the BGP MED attribute.

C.
Metrics for external OSPF router is propagated in the Hop Count field.

D.
OSPF area, route type, and metric type are propagated in an extended BGP community.

Explanation:

MP-BGP attaches two new extended community attributes to the routes redistributed from OSPF:
* OSPF domain identifier extended community attribute
* OSPF route type extended community attribute
MP-BGP uses these attributes and the MED to preserve OSPF routing information across the BGP/MPLS VPN backbone.
Reference: MPLS and VPN Architectures (Ciscopress) page 235


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