cis 171 ch 5

Which statement best describes STP?

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

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?

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

Which of the following ports will forward Ethernet frames? (Choose two.)

designated port, root port

What is an accurate description of redundancy?

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

Which three port states are used by Rapid PVST+? (Choose three.)

discarding, learning, forwarding

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 sum of all port costs to reach the root and use the path with the lowest cost

Which RSTP ports are connected to end devices?

edge port

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.)

edge port, portfast

How often does a switch send a BPDU?

every 2 seconds

Which port state will switch ports immediately transition to when configured for PortFast?

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?

listening

The root bridge will be the switch with the:

lowest bridge id

What value determines the root bridge when all switches connected by trunk links have default STP configurations?

mac address

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

What device is elected by the Spanning Tree Algorithm to which all other switches determine a single least-cost path?

root bridge

The sum of individual port costs along the path from the switch to the root bridge is known as the:

root path cost

The port closest to the root bridge in terms of least overall cost (best path) to the root bridge is the:

root port

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

root port

Which protocol was designed to bring faster convergence to STP?

rstp

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

By default (without any configuration on a switch), what will determine which switch is the root bridge?

the mac address on the switch

Which two statements describe a switch port that is configured with PortFast? (Choose two.)

the switch port immediately transitions from blocking to the forwarding state, the switch port should never recieve bpdus

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

unknown unicast, multicast, broadcast

What additional information is contained in the 12-bit extended system ID of a BPDU?

vlan id