4A0-116 Nokia Segment Routing Exam Questions and Answers

SRGB when SRv6 is configured: This is not required to be advertised, SRGB(Segment Routing Global Block) is only used for SR-MPLS and is not needed when SRv6 is configured. Instead, SRv6 uses the IANA-assigned IPv6 address space.

When an SR-TE LSP with Seamless-BFD enabled, the BFD sessions are established between the routers along the path to detect any failures quickly. If a failure happens in the path, the router will stop forwarding the traffic and send a BFD control packet to the head-end router. In this case, R4 failed, BFD sessions will detect the failure and send a message to the head-end router, but since R4 is a loose hop, the path doesn't have to be re-calculate. The head-end router will continue forwarding traffic to the current next-hop, R2, which will be discarded at the point of failure (R4) as it doesn't know about the failure. And the traffic will not be redirected to R3 after IGP reconvergence.

The data is transparently carried from end to end: This statement is not true, MPLS does not provide data transparency, which means that the data is not carried unmodified from end to end. MPLS uses labels to forward data, so the original IP packets are encapsulated in new MPLS packets, and the original IP headers are not visible at the egress LSR.