Which statement is correct about the inet.3 routing table?
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A. B. C. D.C
The inet.3 routing table in Junos is used to store MPLS label-switched paths (LSPs) and is maintained by the Label Distribution Protocol (LDP) or RSVP-TE (Resource Reservation Protocol with Traffic Engineering) signaling protocol. It is a dynamic table that maps IP prefixes to MPLS labels and is created by the Junos operating system when MPLS is enabled on a router.
Answer A is incorrect because MPLS creates a copy of the inet.0 table and stores it in the mpls.0 table, not the other way around.
Answer B is partially correct. The inet.3 routing table is used by transit routers to identify label values, but it is not the only function of this routing table. The transit routers use this table to determine which label to assign to a packet based on the destination IP address. The MPLS label identifies the LSP that the packet should follow.
Answer C is incorrect. BGP uses the inet.0 and inet.2 routing tables to resolve next hops.
Answer D is incorrect. MPLS does not use the inet.3 routing table to assign labels. Instead, MPLS assigns labels based on the contents of the inet.0 table, which stores the IPv4 forwarding table.
In summary, the correct answer is B: The inet.3 routing table is used by transit routers to identify label values.