Module 5

During the implementation of Spanning Tree Protocol, all switches are rebooted by the network administrator. What is the first step of the spanning-tree election process? Each switch determines the best path to forward traffic. Each switch determines what port to block to prevent a loop from occurring. All the switches send out BPDUs advertising themselves as the root bridge. Each switch with a lower root ID than its neighbor will not send BPDUs.

All the switches send out BPDUs advertising themselves as the root bridge.

The port on the segment (with two switches) that has the lowest path cost to the root bridge is the: Designated port Blocked port or non-designated port Root port Routed Port

Designated port

Which of the following ports will forward Ethernet frames? (Choose two.) Designated port Blocked port or non-dedicated port Root port

Designated port Root port

After the election of the root bridge has been completed, how will switches find the best paths to the root bridge? Each switch will analyze the BID of all neighbors to reach the root and use the path through the lowest BID neighbors. Each switch will analyze the port states of all neighbors and use the designated ports to forward traffic to the root. Each switch will analyze the sum of the hops to reach the root and use the path with the fewest hops. Each switch will analyze the sum of all port costs to reach the root and use the path with the lowest cost.

Each switch will analyze the sum of all port costs to reach the root and use the path with the lowest cost.

How often does a switch send a BPDU? Every 2 seconds Every 15 seconds Every 20 seconds Only when there is a change in the topology

Every 2 seconds

The root bridge will be the switch with the: Lowest bridge ID Highest bridge ID Lowest port priority Highest port priority

Lowest bridge ID

What value determines the root bridge when all switches connected by trunk links have default STP configurations? MAC address extended system ID VLAN ID bridge priority

MAC address

What is one way to correct a spanning tree failure? Insert redundant links to replace the failed STP links. Manually remove redundant links in the switched network. Replace all instances of STP with RSTP. Replace the cables on failed STP links.

Manually remove redundant links in the switched network.

Which is the default STP operation mode on Cisco Catalyst switches? MST PVST+ Rapid PVST+ RSTP MSTP

PVST+

Which technology solves the problem of a device being unable to get an IPv4 address from a DHCP server due to STP forwarding delay timers? PortFast BPUD guard PVST MSTP

PortFast

Which two concepts relate to a switch port that is intended to have only end devices attached and intended never to be used to connect to another switch? (Choose two.) PVST+ PortFast bridge ID extended system ID edge port

PortFast edge port

Which protocol was designed to bring faster convergence to STP? PortFast RSTP PVST MSTP

RSTP

The sum of individual port costs along the path from the switch to the root bridge is known as the: Least cost path Shortest path cost Best path cost Root path cost

Root path cost

The port closest to the root bridge in terms of least overall cost (best path) to the root bridge is the: Designated port Blocked port or non-designated port Root port Routed Port

Root port

Which statement describes STP? STP is a Layer 2 routing protocol. STP is a Layer 3 routing protocol for Ethernet LANs. STP is a Layer 2 loop prevention protocol for Ethernet LANs. STP is a Layer 3 loop prevention protocol for IP networks.

STP is a Layer 2 loop prevention protocol for Ethernet LANs.

By default (without any configuration on a switch), what will determine which switch is the root bridge? The bridge priority The extended system ID The MAC address of the switch The bridge ID

The MAC address of the switch

Which two statements describe a switch port that is configured with PortFast? (Choose two.) The switch port immediately transitions from the listening to the forwarding state. The switch port immediately processes any BPDUs before transitioning to the forwarding state. The switch port immediately transitions from blocking to the forwarding state. The switch port should never receive BPDUs. The switch port sends DHCP requests before transitioning to the forwarding state.

The switch port immediately transitions from blocking to the forwarding state. The switch port should never receive BPDUs.

Without STP on the Ethernet LAN, which three types of frames could cause a catastrophic loop in the network? (Choose three.) Unicast Unknown unicast Multicast Broadcast

Unknown unicast Multicast Broadcast

What additional information is contained in the 12-bit extended system ID of a BPDU? IP address MAC address port ID VLAN ID

VLAN ID

What is an accurate description of redundancy? configuring a switch with proper security to ensure that all traffic forwarded through an interface is filtered designing a network to use multiple paths between switches to ensure there is no single point of failure designing a network to use multiple virtual devices to ensure that all traffic uses the best path through the internetwork configuring a router with a complete MAC address database to ensure that all frames can be forwarded to the correct destination

designing a network to use multiple paths between switches to ensure there is no single point of failure

Which three STP port states are merged into the RSTP discarding port state? (Choose three.) disabled blocking listening learning forwarding

disabled blocking listening

Which port state will switch ports immediately transition to when configured for PortFast? listening forwarding blocking learning

forwarding

Which three port states are used by Rapid PVST+? (Choose three.) forwarding listening trunking blocking learning discarding

learning discarding forwarding

When PVST is running over a switched network, which port state can participate in BPDU frame forwarding based on BPDUs received, but does not forward data frames? blocking forwarding disabled listening

listening

What device is elected by the Spanning Tree Algorithm? All other switches determine a single least-cost path to this device. root bridge dedicated bridge default gateway core switch

root bridge

Which STP port role is adopted by a switch port if there is no other port with a lower cost to the root bridge? alternate root port designated port disabled port

root port

An administrator is troubleshooting a switch and wants to verify if it is a root bridge. What command can be used to do this? show spanning-tree show running-config show vlan show startup-config

show spanning-tree