Question No. 1

Which of the following statements about multi-homing for a Layer-2 service is TRUE?

AIn the single-active mode, the CE requires a LAG to be configured between the CE and all attached PEs.

BIn the single-active mode, the CE forwards traffic to all attached PES and receives traffic from a single PE.

CIn the all-active mode, all PES attached to a CE can forward traffic to and from the CE.

DThe Nokia 7750 SR supports a CE being multi-homed to a maximum of two PEs.

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Correct Answer: C

In the all-active mode, all PEs attached to a CE can forward traffic to and from the CE. This provides load balancing and redundancy for the CE.The CE does not require a LAG to be configured between the CE and all attached PEs1.

Verified Reference:Ethernet Virtual Private Networks (EVPNs)

Question No. 2

In the exhibit, the EVPN-IRB is configured to use the interface-ful unnumbered model. Which of the following statements regarding the route advertisement is FALSE?

APEI advertises an EVPN IP-Prefix route for prefix 10.10.1.0/24 to PE3. The BGP update includes MAC-OI as on overlay index.

BPEI advertises an EVPN MAC route for MAC-OI to PE3. The BGP update includes the route-target value configured for VPRN 15.

CPE3 advertises a VPN-IPv4 route for prefix 10.10.1.0/24 to PE4. The BGP update includes an MPLS service label.

DPE4 advertises an EVPN IP-Prefix route for prefix 10.10.1.0/24 to PE2. The BGP update includes MAC-04 as an overlay index.

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Correct Answer: D

PE4 does not advertise an EVPN IP-Prefix route for prefix 10.10.1.0/24 to PE2.PE4 advertises a VPN-IPv4 route for prefix 10.10.1.0/24 to PE2, which includes the MPLS service label of VPRN 152.

Verified Reference:Nokia Ethernet Virtual Private Network Services Course | Nokia

Question No. 3

Which of the following statements about the operation of a single-homed EVPN VPWS is TRUE?

AThe same tag ID must be configured for the local attachment circuit (AC) at each PE.

BEach PE advertises a MAC route and an A-D per EVI route when its local AC becomes operationally UP.

CThe advertised A-D per EVI route includes a non-zero tag ID and a non-zero MPLS label.

DEach PE verifies that the received tag ID matches its configured local AC tag ID.

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Correct Answer: C

The advertised A-D per EVI route includes a non-zero tag ID and a zero MPLS label.The tag ID is used to identify the VPWS service, while the MPLS label is not used for single-homed VPWS services1.

Verified Reference:Ethernet Virtual Private Networks (EVPNs)

Question No. 4

In the exhibit,

MACI moves from PEI to PE2. Which of the following actions related to this MAC address mobility is performed?

ACEI generates an update message to PEI withdrawing its MAC.

BPEI generates an update message to remote PES identifying the new location of CEI.

CPE2 advertises a MAC/IP route for MACI with a sequence number higher than that received from PEI.

DPE3 waits to receive a data packet from CEI to update its FDB entry for MACI.

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Correct Answer: C

PE2 advertises a MAC/IP route for MAC1 with a sequence number higher than that received from PE1. This indicates that MAC1 has moved from PE1 to PE2 and triggers a MAC withdrawal message from PE1 to remote PEs.CE1 does not generate an update message to PE1 withdrawing its MAC, nor does PE1 generate an update message to remote PEs identifying the new location of CE11.

Verified Reference:Ethernet Virtual Private Networks (EVPNs)

Question No. 5

A Layer-3 EVPN service is configured to use the interface-ful unnumbered forwarding model. Which of the following statements is FALSE?

AEach participating PE advertises a MAC/IP route that carries the MAC address of SBD IRB interface.

BIP-Prefix routes exchanged between PES include a non-zero MAC address as an overlay index.

CThe VPRN service is configured to allow the advertisement of IP prefixes.

DThe SBD IRB interface configured in the VPRN service has no IP address assigned to it.

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Correct Answer: D

The SBD IRB interface configured in the VPRN service has an IP address assigned to it.The IP address is used as a gateway IP address for hosts in the corresponding subnet2.

Verified Reference:Nokia Ethernet Virtual Private Network Services Course | Nokia

Free Nokia 4A0-115 Exam Actual Questions

The questions for 4A0-115 were last updated On Jan 18, 2025