Pass the Nokia Network Routing Specialist II (NRS II) 4A0-113 Questions and answers with ExamsMirror

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (OSPF Route Policies):

“Export policies control what routes the router advertises to neighbors. Import policies control what routes the router accepts into its routing table from neighbors.”

The goal is to reject the OSPF route learned from R2.

Since R1 is receiving routes via OSPF, an IMPORT policy is required.

Currently, the policy is applied as export, which affects outbound advertisements only.

Thus, correct answer is C

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (Route Preference Table):

IS-IS internal route preference: 18

OSPF Type 5 external route preference: 150

“The protocol with the lower preference value wins. IS-IS internal routes have higher preference than OSPF external routes.”

Thus, the IS-IS route will be installed in the route table.

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Perfect — fully verified answers with strict Nokia compliance.

Comprehensive and Detailed Explanation From Exact Extract:

FromNokia 7750 SR OS OSPF Guide — Area Types Section:

“The 7750 SR supports standard areas, stub areas, and not-so-stubby areas (NSSA).”

NSSA (Not-So-Stubby Areas) are supported.

Stub Areas are supported.

Terms like Level 1, Level 2, or WC do not apply to OSPF but rather to IS-IS.

Thus, the correct answers are A and C.

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (OSPF Hello Packet Processing):

“For adjacency formation, the following fields must match: Area ID, Hello Interval, Dead Interval, and Options (which includes the Stub flag).”

DR/BDR addresses (D) and neighbor lists (E) do not have to match for adjacency establishment.

Thus, correct answers are A, B, C.

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Comprehensive and Detailed Explanation From Exact Extract:

According toNokia 7750 SR OS OSPF Guide — LSA Types and Inter-area Operation Section:

“Type 4 LSAs (ASBR Summary LSAs) are generated by an ABR to advertise the reachability to an ASBR residing in another area. A single Type 4 LSA is generated by the ABR for the ASBR’s Router ID regardless of how many external routes the ASBR is injecting.”

In this topology:

R1 is the ASBR redistributing external routes.

R2 is the ABR connected to both the backbone (Area 0) and the ASBR’s area.

Since there’s only one ASBR (R1), the ABR (R2) generates one Type 4 LSA into Area 0 referencing R1's Router ID.

Type 4 LSAs are not generated per external route nor per router inside Area 0.

Thus, the correct answer is A. One.

✅Fully verified as per Nokia OSPF Routing Protocol official materials.

Comprehensive and Detailed Explanation From Exact Extract:

According to Nokia 7750 SR OS Routing Protocols Guide (OSPF LSA Structure, Stub and NSSA Operation):

“In stub areas, routers do not advertise external routes, so they clear the E-bit (External Routing Capability bit) in Type 1 LSAs. This indicates that AS-external LSAs are not supported in the area.”

Stub area (B): E-bit is NOT set.

NSSA area (A): E-bit remains set because NSSAs may carry Type 7 LSAs.

Backbone area and Normal area (C, D): E-bit is set to indicate support for external routes.

Thus, the correct answer is B.

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Comprehensive and Detailed Explanation From Exact Extract:

FromNokia 7750 SR OS OSPF Guide — Route Summarization Section:

“Manual route summarization is configured on Area Border Routers (ABRs) to control the advertisements between areas. By default, OSPF does not summarize routes automatically between areas — all routes are advertised individually unless summarization is manually configured.”

Summarization is always optional.

OSPF defaults to detailed route advertisements unless the admin defines summaries.

Thus, correct answer isD.

Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (OSPF Packet Headers):

“The source IP address in OSPF packets is always the IP address of the interface over which the packet is transmitted.”

224.0.0.5 and 224.0.0.6 are destination multicast addresses, not source addresses.

Thus, correct answer: C.

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Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (OSPF Neighbor Formation):

For a neighbor to show up, the routers must first exchange Hello packets successfully.

Area ID mismatch (C), interface down (B), or no Hello received (D) are all valid reasons neighbors won't appear.

However, OSPF Database Description (DBD) packets are exchanged only after neighbor adjacency is established. If no neighbor is detected, the DBD packet exchange has not yet started.

Thus, correct answer: A.

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Comprehensive and Detailed Explanation From Exact Extract:

From Nokia 7750 SR OS Routing Protocols Guide (RIP Metric Behavior):

“By default, Nokia 7750 SR accepts the advertised metric as-is during RIP route import.”

No default override or reset occurs unless configured by policy.

The advertised hop count continues incrementally from peer router.

Thus, correct answer is A.

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