4A0-105 Online Practice Questions and Answers

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?

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

B. The service MTU must be 1514 bytes.

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

D. The service MTU can be any value.

During the process of troubleshooting a VPLS problem the "oam mac-purge" command with "register" option was used to purge a MAC address from the FDB.

Which of the following statements is true?

A. Relearning of the MAC address that was purged can only be done once customer traffic resumes.

B. Relearning of the MAC address that was purged can only be done with the "oam mac- populate" command.

C. Customer traffic destined to the MAC address that was purged will be dropped until the MAC address is relearned with the "oam mac-populate" command.

D. Relearning of the MAC address that was purged can only be done with the "oam mac- register" command.

Click on the exhibit below.

The MDU attached to this PE has been configured with active/standby SDP's configuration option has been configured for the PE to recognize that this SDP is in standby mode?

A. On the PE the endpoint has been configured with "supress-standby-signalling"

B. On the PE the endpoint has been configured with "no supress-standby-signalling"

C. On the MDU the endpoint has been configured with "supress-standby-signalling"

D. On the MDU the endpoint has been configured with "no supress-standby-signalling1

What are the advantages of running a physical ring topology with a mesh of mesh-SDPs? (Choose 2)

A. STP can be used to break the loop.

B. STP is not required to break the loop because of split-horizon rules.

C. If the traffic is primarily multicast, a full mesh of SDPs is a simple and efficient design.

D. If the traffic is primarily Unicast, a full mesh of SDPs is a simple and efficient design.

Which of the following describes the scope of the IEEE 802.3ah EFM standard? (Choose 3)

A. Monitor and troubleshoot a point-to-point full-duplex link.

B. Monitor and troubleshoot end-to-end services.

C. Can be used at the core to trigger MPLS protection mechanisms when a physical failure detection is not possible.

D. Should not be used at the core to trigger MPLS protection. BFD is the only method that can be used when physical failure detection is not possible.

E. Valuable in the last-mile connection to the Service Provider demarcation device.

Which of the following is a true statement?

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

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

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

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

Why should you configure send-flush-on failure on your PE routers when using active/standby pseudowires?

A. It flushes the local FDB speeding recovery

B. It discards all packets in the queue and sends icmp-discad messages to the sender. The packets are re-transmitted resulting in no loss of data.

C. On failure, the PE sends an LDP flush-all-from-me message to all PE devices in the VPLS. This speeds convergence to the new topology.

D. It is not important to use send-flush-on-failure as Active/Standby signalling automatically converges the FDB in all VPLS instances

What option is available when using PBB to reduce the amount of required VPLS services?

A. The Alcatel-Lucent 7750 SR supports 1:1 mapping of I-VPLS services to B-VPLS services.

B. The Alcatel-Lucent 7750 SR supports 1:1 andM:1 mapping of l-VPLS services to B- VPLS services.

C. The Alcatel-Lucent 7750 SR supports the mapping of multiple, standard VPLS services to B- VPLS services.

D. The Alcatel-Lucent 7750 SR supports the mapping of multiple, standard VPLS services to l- VPLS services.

What is the MTU impact on the SDP path-mtu if fast reroute facilities-mode is implemented on the LSP?

A. There will be no impact on the path-mtu.

B. The path-mtu will decrease by4 bytes.

C. The path-mtu will increase by 4 bytes.

D. The path-mtu will decrease by 8 bytes.

E. The path-mtu will increase by 8 bytes.

What action will be taken when an Ethernet switch receives a frame with a known DA and an outer Ethertype value of 0x0800 on a dot1q encapsulated port?

A. The frame will be forwarded out the port associated with the DA.

B. The frame will be discarded.

C. The frame will be flooded to all ports.

D. The frame will be fragmented and forwarded out the port associated with the DA.

Click on the exhibit below.

Which port will become the alternate port?

A. Bridge B 1/1/3

B. Bridge B 1/1/2

C. Bridge C 1/1/2

D. Bridge C 2/1/1

E. Bridge D 1/1/1

F. Bridge D 1/1/3

G. Bridge E 1/1/1

H. Bridge E 1/1/3

What is PBB also known as?

A. H-VPLS

B. IEEE 802.lag

C. MAC aggregation

D. MAC-in-MAC

What function in IEEE 802.1 ah helps to limit the amount of MAC addresses learned in the core?

A. I-VPLS is configured in the core of the network with an l-MAC address. This l-MAC address is the only MAC learned in the core

B. The B-VPLS and l-VPLS are configured in the edge. The B-VPLS is configured with a Backbone MAC and is the only MAC learned in the core

C. Each SDP is configured with a Backbone MAC to hide customer MAC addresses in the core D. Each SAP is associated with a common l-MAC to hide customer MAC addresses in the core

Which of the following best describes the difference between VPWS and VPLS?

A. Unlike VPLS. VPWS appears as a multi-hop network to the customers.

B. Unlike VPLS, VPWS allows CEs that are member of the same service instance to communicate with each other as if they are connected via a bridged LAN.

C. Unlike VPWS, VPLS allows customers to view the network as a routed network.

D. Unlike VPWS, VPLS is a service where customer MAC addresses are learned.

Which of the following needs to be considered when designing Ethernet networks with redundancy?

A. Processing the TTL takes extra time.

B. MAC learning rate is doubled.

C. FDB size is doubled.

D. Requires a protocol to remove loops.