4A0-105 Sample Questions Answers

There is no effect. The MAC addresses for the l-VPLS age out independently of the aging of B-VPLS addresses.

The MAC addresses for the l-VPLS will age out immediately following the remote-age out of the backbone-macs of the B-VPLS.

By default, the remote-age timer of the B-VPLS is configured to 0 and addresses do not age out. The l-VPLS uses its own timer.

The same timer is used for B-VPLS and l-VPLS addresses on the node.

Spanning tree will be disabled on the SAP that the PVST BPDU was received on.

The SAP that the PVST BPDU was received on will be disabled to prevent loops.

The spanning tree encapsulation will be dynamically changed to PVST on the SAP the PVST BPDU was received on.

The PVST BPDU will be ignored and 802.1D 2004 BPDUs will continue to be transmitted on the SAP.

The time to relearn thousands of MAC addresses may result in excessive flooding or loss of packets.

If the FDB reaches the limit, the router will discard frames.

Discarding frames when the FDB limit is reached could deny SLA guarantees.

It could take several seconds to relearn thousands of MAC addresses denying QoS/SLA guarantees.

STP can be used to break the loop.

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

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

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

Theloopbackfuntionin802.1ag is an intrusive test that will stop customer data.

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

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

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

All untagged frames will be dropped.

The source MAC address of a frame with a top tag of 200 and bottom tag of 300 will be populated in VPLS 3.

All frames with more than one tag will be dropped.

The source MAC address of a frame with a single tag of 500 will be populated in VPLS 1.

The source MAC address of a frame with a top tag of 100 will be populated in VPLS 2.

PE-B will require a SAP id of "sap 1/1/1:500*".

PE-B will require a SAP id of "sap 1/1/1:100*".

PE-B will require a SAP id of "sap 1/1/1:500.200".

PE-B will require a SAP id of "sap 1/1/1:200*".

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

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

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

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

PE-1 must be configured with mesh-SDPs to every node receiving the multicast traffic. There is no way to reduce the replication or bandwidth.

PE nodes in Metro 1 could be configured with mesh-SDPs. PE nodes in Metro 2 would be configured with mesh-SDPs. However, the connection between Metro networks (PE-2 to PE-6) can be configured with a spoke-sdp. This would reduce the replication and bandwidth used on the link between Metro networks. This also reduces the replication required by PE-1.

PE-1 can be configured with spoke-SDPs to every PE node in both Metro networks. This will reduce the bandwidth and replication within the network.

PE nodes in Metro 1 could be configured with spoke-SDPs. PE nodes in Metro 2 would be configured with spoke-SDPs. However, the connection between Metro networks (PE-2 to PE-6) can be configured with a mesh-sdp. This would reduce the replication and bandwidth used on the link between Metro networks. This also reduces the replication required by PE-1.

100

200

1

2

TRUE

FALSE

Designated

Discarding

Listening

Root

Forwarding

discard-unknown

mac-move

disable-learning

enable-mac-stability

sap 1/1/1:200.100

sap 1/1/1:200*

sap 1/1/1:*

sap 1/1/1:0*

Learning should be disabled on both SAPs connected to the DPI device to prevent FDB instability

A MAC filter should be applied to both SAPs connected to the DPI to limit MAC learning on the port

An IP filter should be applied to both SAPs connected to the DPI to prevent FDB instability

The SAPs connected to the DPI should be configured with the "discard-unknown" feature to limit MAC learning on the port

4094

8190

32768

131071

Loss of connectivity.

Unidirectional Loss.

Loop detection.

Merged Services.

End-to-end bit error rates.

LDP must be enabled.

RSVP must be enabled.

An SDP must be configured on the far-end.

Service MTU must match.

SDP ID must match.

Multicast frames only forward out ports that have a known receiver.

Unicast frames only forward out ports that have a known receiver.

If the FDB is empty, unicast and multicast frames are treated equally.

If the FDB has an entry for the unicast frame, both unicastand multicast are treated equally.

Spanning-tree BPDUs are returned to the sender.

The MEP sees its own CFM frames returned to itself.

This is not a function of IEEE 802.lag but of 802.1D

The record field of the CFM frame keeps track of chassis-mac addresses.

Configure the local age timer to be larger.

Configure the local age timer to be lower.

Configure the remote age timer to be larger.

Configure the remote age to be lower.

Broadcast traffic will be flooded.

If the unicastSA has not been learned in the FDB, the frame will be dropped.

If the unicast DA has not been learned in the FDB, the frame will be dropped.

All traffic will be dropped, including multicast and broadcast.

Broadcast traffic will be dropped.

TRUE

FALSE

MEP

MAP

MIP

MUP

TRUE

FALSE

802.1D2004

802.1D 1998

comp-dot1w

PVST

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

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

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

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

Mesh-sdp

Spoke-sdp

MPLS

GRE

oam mac-ping

oam mac-populate

oamsvc-ping

oam mac-trace

The CE must be configured with an MC-LAG to both PE devices.

The CE must be configured with LACP in active mode.

There is no configuration required on the CE.

The CE must be an Nokia 7750 SR.

TRUE

FALSE

H-VPLS

IEEE 802.lag

MAC aggregation

MAC-in-MAC

A Spanning Tree BPDU will be sent across the mesh flushing the FDB table in all devices participating in the VPLS instance.

Stale information will be used within the VPLS instance to forward traffic until the FDB ages out.

An LDP control message will be sent to all devices in the mesh participating in the VPLS instance. Only MAC addresses associated with the PE that the failure occurred on will be flushed.

An LDP control message will be sent to all devices in the mesh participating in the VPLS instance. The entire FDB in the VPLS instance will be flushed.

ports must be on the same MDA

ports must have the same speed and duplex settings

auto negotiation must be on

auto negotiation must be off or limited

port must be in access mode only

9100 bytes

9104 bytes

9108 bytes

9118 bytes

Yes

No

The customer-id in this command is 9000.

The service-id in this command is 9000.

This value 9000 should be unique across the network as a best practice.

The vc-id will be 6 for the service by default.

The egress vc-label will be 9000.

If the MAC address of this new client device does not reach the upper limit of the configured total number of MAC addresses allowed in the VPLS forwarding database, then the new MAC address will be stored.

The new source MAC addresses will not be entered in the VPLS service forwarding database.

New local source MAC addresses will not be entered in the VPLS service forwarding database, but new remote MAC addresses would continue to be entered.

New remote source MAC addresses will not be entered in the VPLS services forwarding database, but new local MAC addresses would continue to be entered.

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

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

The switch with the highest MAC address is selected as root

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

9100

9104

9108

9122

9126

TRUE

FALSE

The loopback control PDU instructs the remote port to enter loopback mode.

Putting a port in loopback does not affect customer data flow

Both ports must rediscover the OAM capabilities of each other once the port is put back into service.

Both ports must still send Information PDUs to avoid going back to discovery mode.

When a port is in loopback mode, service mirroring will still work if it is a mirror-source or mirror-destination.

All packets, except for information PDUs, are looped back.

On initialization and then every hello-interval.

Only after receiving LACP packets.

Every 1 second.

Never.