JN0-363 Exam Dumps : Service Provider Routing and Switching, Specialist (JNCIS-SP)

In segment routing, SIDs (Segment Identifiers) are used to identify different types of segments that can be traversed. A node SID represents an instruction to route a packet to a particular node, and an adjacency SID represents an instruction to route a packet over a specific link or adjacency between two nodes.

References

• Juniper Networks Technical Documentation on Segment Routing

In MPLS, multiple paths can be merged if they share the same egress router. In the given scenario, traffic from Network 1 to Network 3 and Network 4 can be engineered to follow the same label-switched path (LSP) within the MPLS network until they reach the last common point before diverging to their respective destinations.

As for R3 performing label operations, in a typical MPLS network, intermediate routers (like R3) perform label swapping. They replace the incoming label with a new label before forwarding the packet along the LSP. A label pop operation is typically performed by the egress router in the case of an ultimate hop pop (UHP), where it removes the MPLS label before delivering the packet to the final destination outside the MPLS domain.

References

• Juniper Networks Technical Documentation on MPLS
• Understanding MPLS Label Operations (Swap, Push, and Pop) - Juniper Networks

In MPLS (Multiprotocol Label Switching) networks, routers use label switching to forward packets. The first router at the edge of the MPLS network (R1) will perform a lookup in the mpls.0 table to determine the label to attach to the packet as it enters the MPLS network. This label informs the next routers in the MPLS network (like R2) on how to forward the packet. Internal MPLS routers, like R2, also perform lookups in their mpls.0 table to determine how to switch the packet toward its destination (label swapping). The inet.3 table is used for resolving next-hop information for labeled routes, but it's the mpls.0 table that is used for label switching decisions.

References:

• Juniper Networks documentation on MPLS: MPLS Applications User Guide for Routing Devices