The mapping of labels in a Multi-protocol label switching (MPLS) network domain is maintained by which of the following?

In a Multi-Protocol Label Switching (MPLS) network, the mapping of labels is critically maintained by the Label Forwarding Information Base (LFIB). The LFIB is a data structure used by MPLS routers that contains the information necessary to forward packets based on their assigned labels. Each entry in the LFIB corresponds to a specific label and defines how packets with that label should be processed, including information like the next hop and the outgoing interface. This allows for efficient packet forwarding by leveraging labels instead of relying solely on network addresses.

The LFIB operates alongside the Label Information Base (LIB), which keeps track of all the labels and their associated information such as upstream or downstream labels. However, the LFIB is specifically the component that dictates how labels are used to direct packet forwarding through the network.

In contrast, the other options represent various aspects of routing and forwarding in a network but do not specifically pertain to the label mapping utilized in MPLS. For example, the Forwarding Information Base (FIB) is used in general IP routing and doesn't manage labels specifically. The Label Distribution Protocol (LDP) is involved in the signaling and distribution of labels but does not maintain the actual forwarding mappings. Lastly, the Multi-Protocol Routing Table