ESTUDYR
NOKIA NETWORK ROUTING SPECIALIST I (NRS I)
CERTIFICATION MOST TESTED QUESTIONS AND ANSWERS
GRADED A+ WITH RATIONALES
Which TCP/IP layer is responsible for path determination and end-to-end
forwarding of datagrams?
A. The Application layer
B. The Transport layer
C. C. The Internet layer ✔
D. The Link layer
Rationale: The Internet layer (IP) handles routing, path determination, and
forwarding of IP datagrams between hosts.
What information is part of the encapsulation done at the Link layer?
A. Source and destination IP addresses
B. Source and destination port numbers
C. Source and destination email addresses
D. D. Source and destination MAC addresses ✔
Rationale: Link-layer frames include MAC (hardware) source and destination
addresses for local delivery.
Which of the following is NOT a function of the control plane in a router?
A. Exchange control messages with other routers
B. Collaborate with other routers to compute best paths
C. Populate the routing table and tunnel table
D. D. Forward data packets towards their destination ✔
Rationale: Forwarding is a data-plane function; the control plane handles routing
protocol and table population.
Which shows a typical data packet flow when egressing a Nokia 7750 SR?
A. SF/CPM -> MDA -> IOM -> SFP
B. SF/CPM -> SFP -> IOM -> MDA
C. C. SF/CPM -> IOM -> MDA -> SFP ✔
,ESTUDYR
D. MDA -> IOM -> SF/CPM -> SFP
Rationale: Packets exit the switch fabric (SF/CPM), pass through I/O modules
(IOM), then MDA to the SFP interface.
Which statement about MD-CLI is FALSE?
A. MD-CLI allows atomic transactions.
B. Multiple users may edit the global candidate configuration concurrently.
C. Configuration changes are activated when a candidate configuration datastore
is committed.
D. D. Uncommitted configuration changes are saved when a user exits the
private configuration edit mode. ✔
Rationale: Uncommitted changes are not saved on exit from private edit mode —
they are discarded unless committed.
If one user is in private configuration edit mode and another in read-only mode,
which candidate datastore do they each access?
A. Both users access the global configuration datastore.
B. Both users access the same private configuration datastore.
C. C. Read-only user: global datastore; private user: their own private datastore.
✔
D. Read-only user: running datastore; private user: global datastore.
Rationale: The private editor works on a user-specific candidate; read-only sees
the global (committed) config.
Which action exits the MD-CLI implicit configuration mode?
A. Navigating to a CLI context outside the configuration branch
B. B. Navigating to the root CLI context ✔
C. Issuing a full show command
D. Issuing the quit-config command
Rationale: Returning to the root CLI context exits implicit config mode; other
actions may not.
Which command displays the hierarchical structure of available CLI commands
at the current context?
, ESTUDYR
A. show
B. info
C. C. tree ✔
D. help
Rationale: tree lists command hierarchy for the current CLI context.
Which of the following is NOT a valid log destination in a Nokia 7750 SR?
A. A. Main ✔
B. CLI
C. Syslog
D. Console
Rationale: Typical log destinations include CLI, Syslog, Console; “Main” is not a
standard log target.
Which of the following is NOT a characteristic of a hub?
A. It can interconnect hosts in the same LAN.
B. It replicates Ethernet frames across all ports except the receiving port.
C. C. It inspects layer-2 frame headers. ✔
D. Devices connected must operate in half-duplex mode.
Rationale: Hubs are physical repeaters and do not inspect frame headers (no
switching intelligence).
Which address type is used to send frames to all devices in a Local Area
Network?
A. Anycast
B. Multicast
C. C. Broadcast ✔
D. Unicast
Rationale: Broadcast frames (e.g., ff:ff:ff:ff:ff:ff at L2) target all hosts on the LAN
segment.
What happens when a switch receives a frame with an unknown source MAC
and destination ff:ff:ff:ff:ff:ff?
A. Destination saved in MAC FDB; frame discarded.
NOKIA NETWORK ROUTING SPECIALIST I (NRS I)
CERTIFICATION MOST TESTED QUESTIONS AND ANSWERS
GRADED A+ WITH RATIONALES
Which TCP/IP layer is responsible for path determination and end-to-end
forwarding of datagrams?
A. The Application layer
B. The Transport layer
C. C. The Internet layer ✔
D. The Link layer
Rationale: The Internet layer (IP) handles routing, path determination, and
forwarding of IP datagrams between hosts.
What information is part of the encapsulation done at the Link layer?
A. Source and destination IP addresses
B. Source and destination port numbers
C. Source and destination email addresses
D. D. Source and destination MAC addresses ✔
Rationale: Link-layer frames include MAC (hardware) source and destination
addresses for local delivery.
Which of the following is NOT a function of the control plane in a router?
A. Exchange control messages with other routers
B. Collaborate with other routers to compute best paths
C. Populate the routing table and tunnel table
D. D. Forward data packets towards their destination ✔
Rationale: Forwarding is a data-plane function; the control plane handles routing
protocol and table population.
Which shows a typical data packet flow when egressing a Nokia 7750 SR?
A. SF/CPM -> MDA -> IOM -> SFP
B. SF/CPM -> SFP -> IOM -> MDA
C. C. SF/CPM -> IOM -> MDA -> SFP ✔
,ESTUDYR
D. MDA -> IOM -> SF/CPM -> SFP
Rationale: Packets exit the switch fabric (SF/CPM), pass through I/O modules
(IOM), then MDA to the SFP interface.
Which statement about MD-CLI is FALSE?
A. MD-CLI allows atomic transactions.
B. Multiple users may edit the global candidate configuration concurrently.
C. Configuration changes are activated when a candidate configuration datastore
is committed.
D. D. Uncommitted configuration changes are saved when a user exits the
private configuration edit mode. ✔
Rationale: Uncommitted changes are not saved on exit from private edit mode —
they are discarded unless committed.
If one user is in private configuration edit mode and another in read-only mode,
which candidate datastore do they each access?
A. Both users access the global configuration datastore.
B. Both users access the same private configuration datastore.
C. C. Read-only user: global datastore; private user: their own private datastore.
✔
D. Read-only user: running datastore; private user: global datastore.
Rationale: The private editor works on a user-specific candidate; read-only sees
the global (committed) config.
Which action exits the MD-CLI implicit configuration mode?
A. Navigating to a CLI context outside the configuration branch
B. B. Navigating to the root CLI context ✔
C. Issuing a full show command
D. Issuing the quit-config command
Rationale: Returning to the root CLI context exits implicit config mode; other
actions may not.
Which command displays the hierarchical structure of available CLI commands
at the current context?
, ESTUDYR
A. show
B. info
C. C. tree ✔
D. help
Rationale: tree lists command hierarchy for the current CLI context.
Which of the following is NOT a valid log destination in a Nokia 7750 SR?
A. A. Main ✔
B. CLI
C. Syslog
D. Console
Rationale: Typical log destinations include CLI, Syslog, Console; “Main” is not a
standard log target.
Which of the following is NOT a characteristic of a hub?
A. It can interconnect hosts in the same LAN.
B. It replicates Ethernet frames across all ports except the receiving port.
C. C. It inspects layer-2 frame headers. ✔
D. Devices connected must operate in half-duplex mode.
Rationale: Hubs are physical repeaters and do not inspect frame headers (no
switching intelligence).
Which address type is used to send frames to all devices in a Local Area
Network?
A. Anycast
B. Multicast
C. C. Broadcast ✔
D. Unicast
Rationale: Broadcast frames (e.g., ff:ff:ff:ff:ff:ff at L2) target all hosts on the LAN
segment.
What happens when a switch receives a frame with an unknown source MAC
and destination ff:ff:ff:ff:ff:ff?
A. Destination saved in MAC FDB; frame discarded.
