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

Segment routing is a source routing paradigm that allows a source router to define the path that a packet will take through the network by assigning an ordered list of segments—identifiers that specify a forwarding path for the packet through the network. Segment Routing can be implemented over an MPLS architecture or with IPv6 (SRv6).

A. Segment routing does not require a full mesh of adjacencies or state per transit path in the network, which is often the case with conventional MPLS signaling protocols like RSVP-TE. It leverages the existing IGP topology for forwarding without the need to maintain a state for each LSP (Label Switched Path), hence requiring very little resources to maintain.

B. In segment routing, labels (or segments) are distributed via IGP routing protocols like OSPF or IS-IS with extensions to carry segment routing information. These protocols are enhanced with Segment Routing extensions to distribute labels. For example, OSPFv2 is extended with Segment Routing extensions defined in RFC 8665.

C. This statement is not entirely correct. While it is true that segment routing does not require the maintenance of a state for each path (LSP), the concept of "segment routing adjacencies" is a mischaracterization. Segment routing leverages the existing adjacencies formed by the underlying IGP.

D. Label assignments in segment routing are not advertised through LDP (Label Distribution Protocol) updates. Segment routing does away with LDP and instead uses IGP extensions to distribute labels.

References:

• Juniper Networks documentation on Segment Routing: Segment Routing Overview
• Juniper Networks technical documentation providing guidance on configuring OSPF with Segment Routing extensions.
• IETF RFC 8665: OSPF Extension for Segment Routing.

In the given exhibit, interfacege-0/0/0is configured to accept VLANs 101-120 andge-0/0/1is configured with flexible VLAN tagging, which means it can tag traffic with any VLAN ID specified. However, only VLAN 200 is explicitly mentioned forge-0/0/1.A. Traffic tagged with VLAN 101 will pass throughge-0/0/0and will egress onge-0/0/1with the same VLAN tag, because the VLAN ID is within the allowed range on both interfaces.B. VLAN 100 is not specified in the allowed VLAN range forge-0/0/0(which is 101-120),nor is it specified underge-0/0/1. Therefore, it will be dropped.References:

• Understanding VLAN Tagging, Juniper TechLibrary
• Configuring VLANs for EX Series Switches, Juniper TechLibrary

The root bridge in a spanning-tree network is the bridge with the smallest or the lowest bridge ID.

In the absence of a manually configured priority, the Spanning Tree Protocol (STP) elects the root bridge based on the lowest bridge ID, which is a combination of the priority and the MAC address. The device with the lowest MAC address will have the lowest bridge ID and thus be elected as the root bridge.

References

• Juniper Networks Technical Documentation on STP