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1 Refer to the graphic. Server sends
an ARP request for the MAC address of its default gateway. If STP is not enabled,
what will be the result of this ARP request?
Router_1 will kill the broadcast and reply with the MAC address of the next
Switch_A will reply with the MAC address of the Router_1 E0 interface.
Switch_A and Switch_B will continuously flood the message onto the network.
Switch_B will broadcast the request and reply with the Router_1 address.
The message will cycle around the network until its TTL is exceeded.
2 How is the information contained in BPDUs used by switches? (Choose two.)
to prevent loops by sharing bridging tables between connected switches
to set the duplex mode of a redundant link
to determine the shortest path to the root bridge
to determine which ports will forward frames as part of the spanning tree
to activate looped paths throughout the network
3 What elements will exist in a converged network with one spanning tree? (Choose
one root bridge per network
all non-designated ports forwarding
one root port per non-root bridge
multiple designated ports per segment
one designated port per network
4 Which of the following criteria does a switch use to select the root
bridge? (Choose two.)
number of ports
base MAC address
5 How does a switch forward a multicast frame through the network?
It floods it to all ports as a broadcast.
It is forwarded only to ports that contain the destination address.
It is sent to the port that contains the first destination address.
It floods it to all ports except the one it was received on.
It is dropped and not sent to any address.
6 What happens when there is a topology change on a network that utilizes STP
? (Choose two.)
User traffic is disrupted until recalculation is complete.
The switch recomputes the Spanning Tree topology after the network converges.
All ports are placed in learning state until convergence has occurred.
A delay of up to 50 seconds is incurred for convergence of the new Spanning Tree
User data is forwarded while BPDUs are exchanged to recompute the topology.
7 How much time does it take for a switch port to go from the blocking state
to the forwarding state?
8 Following a link failure, when does Rapid Spanning Tree Protocol allow
point-to-point and edge type links to go to the forwarding state?
in 15 seconds
in 30 seconds
after 90 seconds
9 What will be the port assignments and port states in the STP-enabled
network shown in the graphic? (Choose two.)
Port 1/1 will be a root port, 1/11 will be a designated port.
Port 1/1 will be a designated port, Port 1/11 will be a root port.
Port 1/2 will be a root port, 1/12 will be a designated port.
Port 1/1 will be blocked
Port 1/12 will be blocked.
10 Which algorithm is used to create a loop free switched topology?
Shortest Path First
11 Which of the following are problems that can occur in redundantly switched
networks? (Choose three.)
corrupted ARP tables
duplicate MAC addresses
inaccurate routing tables
multiple copies of Ethernet frames
MAC address table instability
12 How can a network administrator influence which STP switch becomes the
Configure the switch as the static root bridge.
Change the BPDU to a higher value than that of the other switches in the
Change the BPDU to a lower value than that of the other switches in the network.
Set the switch priority to a smaller value than that of the other switches in
Set the switch priority to a higher value than that of the other switches in the
13 What features of the Spanning-Tree Protocol contribute to the time it
takes for a switched network to converge after a topology change occurs? (Choose
the max-age timer
the listening forward delay
the spanning-tree hold down timer
the learning forward delay
the spanning-tree path cost
the blocking delay
14 Which of the following are valid STP port states? (Choose three.)
15 How often are BPDUs sent by default in a network using the spanning-tree
every two seconds
every three seconds
every four seconds
16 In which STP state does a port record MAC addresses but not forward user
17 What is meant by "five nines" network uptime?
A network should be available until 9:00 pm five days of the week.
A network should be functioning 99.999% of the time.
There should be five nine-port uplinks for each backbone segment.
Five percent of network expenditures should address 99% of user requirements.
Nothing short of 100% network uptime is acceptable in modern networks.
18 Refer to the network shown in the graphic. Host1 needs to transfer data to
host2, but host1 has no MAC address entry in its ARP cache for host2. What will
happen on the network as host1 prepares to transmit its data to host2?
Host1 will receive an ICMP destination unknown message from switch3.
All hosts in the network shown will receive an ARP request message from host1.
Multicasting will occur until host2 is located.
Switch3 will send the host2 MAC address from its bridging table to host1.
A broadcast storm will occur.
19 What link types have been defined for Rapid Spanning-Tree Protocol? (Choose
20 What characteristic of Ethernet makes a redundantly switched network prone
Routers are only able to prevent loops at Layer 3, while Ethernet exists at
The Ethernet protocol has no TTL mechanism.
Switches lack the sophisticated software required to prevent loops.
Looping of frames is a reliability mechanism built in to the Ethernet protocol.
21 What is the first step in the process of convergence in a spanning tree
election of the root bridge
determination of the designated port for each segment
blocking of the non-designated ports
selection of the designated trunk port
activation of the root port for each segment
22 Switch_A and Switch_B shown in the graphic receive an ARP request from the
host and forward it out their ports. The switches receive the forwarded requests
from each other and in turn flood the requests again. What will be the result if
this process continues?
a broadcast storm
ARP table errors
MAC address instability
redundant unicast frame forwarding
23 In which STP state does a switch port transmit user data and learn MAC
24 Which of the following describe the BIDs used in a spanning tree topology?
They are sent out by the root bridge only after the inferior BPDUs are sent.
They consist of a bridge priority and MAC address.
Only the root bridge will send out a BID.
They are used by the switches in a spanning tree topology to elect the root
The switch with the fastest processor will have the lowest BID.
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