Juniper JN0-363 - Service Provider Routing and Switching, Specialist (JNCIS-SP)

The diagram you provided shows two routers, Router A and Router B, with MPLS labels between them. In the context of segment routing with MPLS, each router advertises a set of SIDs (Segment Identifiers). These SIDs can be node SIDs, which are associated with the router itself, or adjacency SIDs, which are associated with the links between routers.

Given the information from the exhibit:

Router A has a Router ID of 10.1.1.1 and is associated with the MPLS label 11.

Router B has a Router ID of 10.1.1.2 and is associated with the MPLS label 12.

The adjacency SID in segment routing is used to identify a specific adjacency between two routers. In this case, the question is asking for the adjacency SID that Router B advertises to Router A. This would be the label that Router B tells Router A to use to send packets directly to Router B over their shared adjacency.

So, the adjacency SID that Router B advertises would be associated with the link that Router A would use to send traffic to Router B, which is labeled with the number 12 in the exhibit.

Therefore, the answer to the question is:

D. 12

This is the label that packets would carry when being sent from Router A to Router B to identify the specific adjacency between the two routers in the context of segment routing.

In the OSPF routing table output, prefixes are marked with different route types. An external prefix injected into OSPF is marked as 'Ext' (External) followed by a number that indicates whether it's an E1 or E2 route. The prefix 172.18.1.0/24 is marked as Ext2, which indicates that it is an external route that has been redistributed into OSPF from another routing protocol or static configuration.

References

Juniper Networks Technical Documentation on OSPF

The policy statement shown in the exhibit has a term that specifies load-balance per-packet, which indicates that per-packet load balancing is being used. This means that the routing device will distribute packets out multiple paths on a per-packet basis, rather than on a per-flow (per-destination or per-source-destination pair) basis.

IPv6 link-local addresses are automatically generated for each interface and have a prefix of fe80::/10. The interface's MAC address is typically used as part of the process to create the Interface Identifier (IID) in the link-local address, following the EUI-64 format.

References

Juniper Networks Technical Documentation on IPv6

IPv6 Interface Addresses - Juniper Networks

In the given exhibit, interface ge-0/0/0 is configured to accept VLANs 101-120 and ge-0/0/1 is configured with flexible VLAN tagging, which means it can tag traffic with any VLAN ID specified. However, only VLAN 200 is explicitly mentioned for ge-0/0/1.

A. Traffic tagged with VLAN 101 will pass through ge-0/0/0 and will egress on ge-0/0/1 with 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 for ge-0/0/0 (which is 101-120), nor is it specified under ge-0/0/1. Therefore, it will be dropped.

The Segment Routing Global Block (SRGB) defines a range of MPLS labels reserved for segment routing. With an SRGB starting label of 10,000 and an index range of 500, the first usable label is indeed 10,001 because label 10,000 is typically reserved and not used for forwarding. The last usable label would be 10,499 because the range includes 500 labels starting from 10,001.

https://www.juniper.net/documentation/us/en/software/junos/mpls/topics/topic-map/lsp-routers.html

In an MPLS network, the types of routers include ingress routers (where the MPLS labels are first applied), egress routers (where MPLS labels are removed), and transit routers (which switch MPLS-labeled packets through the MPLS network). Peering routers and aggregation routers are not specific types of MPLS routers; they are general network terms.

A route being hidden in BGP usually indicates a configuration that prevents it from being used, such as a next-hop that is not reachable.

B. Configuring a routing policy on R1 that sets the next-hop to the address used for IBGP peering ensures reachability of the next-hop within the local AS.

D. Applying the correct routing policy as an export policy to the IBGP group on R1 will share the route with the IBGP peers, in this case, R2 and R3.

A router’s priority for becoming the designated router is indicated by an arbitrary number from 0 through 127, which you configure on the IS-IS interface. The router with the highest priority becomes the designated router for the area (Level 1, Level 2, or both), also configured on the IS-IS interface. If routers in the network have the same priority, then the router with the highest MAC address is elected as the designated router. By default, routers have a priority value of 64.

https://www.juniper.net/documentation/us/en/software/junos/is-is/topics/concept/routing-protocol-is-is-security-designated-router-understanding.html

The adjacency SID in segment routing is advertised by one router to inform another about the label that should be used to forward traffic to it over a particular link. In this scenario, Router B would advertise an adjacency SID to Router A, which would be used by Router A to forward traffic to Router B. Based on the exhibit, the adjacency SID that Router B advertises to Router A would be 12.