Free Practice Questions for Nokia 4A0-105 Exam

Question 1

Which of the following is a true statement?

AIn a dynamic environment where MAC addresses are changing rapidly, the lower the age-time, the larger the fdb-table-size should be.

BIn a dynamic environment where MAC addresses are changing rapidly, the higher the age-time, the larger the fdb-table-size should be.

CIn a dynamic environment where MAC addresses are changing rapidly, the higher the age-time, the smaller the fdb-table-size should be.

DThere is no relationship between the age-time and the fdb-table-size.

Correct Answer: B. In a dynamic environment where MAC addresses are changing rapidly, the higher the age-time, the larger the fdb-table-size should be.

Question 2

How does the IEEE 802.1ag loopback function differently from the loopback feature in 802.3ah? (Choose 2)

ATheloopbackfuntionin802.1ag is an intrusive test that will stop customer data.

BThe loopback function of 802.lag is a non-intrusive 'ping' sent from a MEP to a remote MEP or MIP.

CThe loopback function in 802.3ah is an intrusive test that will loop customer data.

DThe loopback function of 802.lag is an intrusive test that will 'loop' all customer data back to the original sender.

Correct Answer: B. The loopback function of 802.lag is a non-intrusive 'ping' sent from a MEP to a remote MEP or MIP.; C. The loopback function in 802.3ah is an intrusive test that will loop customer data.

Explanation:

Topic 2, Volume B

Question 3

Which of the following statements about the VC-ID is false?

AThe vc-id is signaled in the control plane.

BThe vc-id is part of the data plane encapsulation.

CThere is a vc-id to vc-label mapping.

DThe vc-id has point to point significance.

Correct Answer: B. The vc-id is part of the data plane encapsulation.

Question 4

Which of the following OAM tools can be used as a VPLS topology discovery mechanism (Choose 2)?

Aoam mac-ping

Boam mac-populate

Coamsvc-ping

Doam mac-trace

Correct Answer: A. oam mac-ping; D. oam mac-trace

Question 5

What scaling factors should a network engineer be aware of when designing VPLS networks? (Choose 3)

AControl plane scaling.

BData plane scaling.

CNetwork touches.

DRoute table reduction.

EOAM tools.

Correct Answer: A. Control plane scaling.; B. Data plane scaling.; C. Network touches.

Question 6

How is MAC learning achieved in traditional Ethernet switches?

AAs frames leave the switch, the DA is populated into the FDB.

BAs frames enter the switch, the DA is populated into the FDB.

CAs frames leave the switch, the SA is populated into the FDB.

DAs frames enter the switch, the SA is populated into the FDB.

Correct Answer: D. As frames enter the switch, the SA is populated into the FDB.

Question 7

Which of the following must be true in order to add a port to a LAG? (Choose 2)

Aports must be on the same MDA

Bports must have the same speed and duplex settings

Cauto negotiation must be on

Dauto negotiation must be off or limited

Eport must be in access mode only

Correct Answer: B. ports must have the same speed and duplex settings; D. auto negotiation must be off or limited

Question 8

Click on the exhibit below.

The VPLS service MTU on R2 is 1514 bytes. What must the service MTU be on all other routers participating in the VPLS?

AThe service MTU must be equal to or smaller than 1514 bytes.

BThe service MTU must be 1514 bytes.

CThe service MTU must be equal to or greater than 1514 bytes.

DThe service MTU can be any value.

Correct Answer: B. The service MTU must be 1514 bytes.

Question 9

In RSTP, how is the root bridge selected?

AThe switch with the highest bridge-id is selected as root.

BThe switch with the lowest bridge-id is selected as root.

CThe switch with the highest MAC address is selected as root

DThe switch with the lowest MAC address is selected as root.

Correct Answer: B. The switch with the lowest bridge-id is selected as root.

Question 10

Which of the following are required for an operational mesh-sdp binding for bidirectional traffic when signaling is enabled within the SDP? (Choose 3)

ALDP must be enabled.

BRSVP must be enabled.

CAn SDP must be configured on the far-end.

DService MTU must match.

ESDP ID must match.

Correct Answer: A. LDP must be enabled.; C. An SDP must be configured on the far-end.; D. Service MTU must match.

Question 11

Which of the following functions must a PE router support when participating in a VPLS service? (Choose 3)

AMAC learning

BFrame replication

CFrame fragmentation

DFrame forwarding

EMust discard frames with an unknown destination MAC

FMSTP

Correct Answer: A. MAC learning; B. Frame replication; D. Frame forwarding

Question 12

Click on the exhibit below.

Which ports will become root ports? (Choose 3)

ABridge B 1/1/3

BBridge B 1/1/2

CBridge C 1/1/2

DBridge C 2/1/1

EBridge D 1/1/1

FBridge D 1/1/3

GBridge E 1/1/1

HBridge E 1/1/3

Correct Answer: B. Bridge B 1/1/2; D. Bridge C 2/1/1; F. Bridge D 1/1/3

Question 13

When a PE node receives a PBB encapsulated frame on a B-VPLS, how does the PE determine which l-VPLS it belongs to?

AThe l-TAG in the l-SID is inspected to determine where the frame should be delivered.

BWhen the B-MAC header is stripped the customer MAC address is then looked up in the FDB

CThe l-SID in the l-TAG is inspected to determine where the frame should be delivered.

DThe PE inspects the service label in the MPLS header before stripping the B-MAC header.

Correct Answer: C. The l-SID in the l-TAG is inspected to determine where the frame should be delivered.

Question 14

How do user VPLSs become associated with a management VPLS for redundant spoke-sdp connections?

AThe association must be defined in the user VPLS service.

BThe association is done when the user VPLS is associated with the same sdp-id in the management VPLS

CThe association is based on service IDs.

DThe association is based on customer IDs.

Correct Answer: B. The association is done when the user VPLS is associated with the same sdp-id in the management VPLS

Question 15

RSTP blocks a spoke-sdp using a management VPLS. Is traffic affected on an ES using the same transport SDP?

AYes

BNo

Correct Answer: A. Yes