Which of the following statements about MPLS forwarding mechanisms are true?

The statement indicating that all of the provided statements about MPLS forwarding mechanisms are true accurately reflects the functioning of the Multi-Protocol Label Switching (MPLS) architecture.

Device queries in the FIB (Forwarding Information Base) table after an IP packet enters an MPLS domain are an essential part of how MPLS operates. When a packet with an IP header comes into an MPLS domain, the MPLS-capable router will look up the FIB table to determine the appropriate label to attach to the packet for efficient forwarding. This ensures that the packet is processed according to the routing policies associated with MPLS.

Regarding the automatic assignment of a tunnel ID to upper-layer applications, this is also a valid statement. In MPLS, when traffic is encapsulated for transport through a Label Switched Path (LSP), the tunnel ID helps to identify the correct path and associated resources at the forwarding layer, thus streamlining the data transfer without requiring upper-layer applications to handle complex routing decisions.

The notion that if the tunnel ID is 0x0, the MPLS forwarding process starts is correct as well. A tunnel ID of 0x0 is typically used to signal that the packet should be forwarded based on standard routing rather than an established