1. Spanning Tree Protocol IEEE 802.1s defines the ability to deploy which of these?
哪个是生成树协议802.1s的定义。?
A. one global STP instance for all VLANs
B. one STP instance for each VLAN
C. one STP instance per set of VLANs
D. one STP instance per set of bridges Answer:
答案：C考试用书
2. Which two of these are used in the selection of a root bridge in a network utilizing Spanning Tree Protocol IEEE 802.1D? (Choose two.)
在生成树协议802.1D中，选择根桥需要用到那两个参数?
A. Designated Root Cost
B. bridge ID priority
C. max age
D. bridge ID MAC address
E. Designated Root Priority
F. forward delay Answer:
答案BD
3. If a port configured with STP loop guard stops receiving BPDUs, the port will be put into which state?
网桥的优先级 网桥的MAC地址
在STP中一个接口停止接收BPDU信息了，那么这个接口是什么状态?
A. learning state B. listening state C. forwarding state D. root-inconsistent state
Answer: D
4. What is the purpose of the STP PortFast BPDU guard feature?
根状态发生了改变
什么是生成树开启PortFast BPDU保护功能的目的
A. enforce the placement of the root bridge in the network B. ensure that a port is transitioned to a forwarding state quickly if a BPDU is received C. enforce the borders of an STP domain
Answer: C
5. When STP UplinkFast is enabled on a switch utilizing the default bridge priority, what will the new bridge priority be changed to?
配置了生成树域的边界
D. ensure that any BPDUs received are forwarded into the STP domain
当STP的uplink Fast端口上使用了一个默认优先级的交换机， 这个交换机的优先级将变成什 么?
A. 8192 B. 16384 C. 49152 D. 65535
Answer: C
6. Which of these best describes the actions taken when a VTP message is received on a switch configured with the VTP mode "transparent"?
那一项最能说明，收到的VTP信息是从透明模式的交换机收到的?
A. VTP updates are ignored and forwarded out all ports. B. VTP updates are ignored and forwarded out trunks only. C. VTP updates are made to the VLAN database and are forwarded out trunks only. D. VTP updates are ignored and are not forwarded.
Answer: B
7. The classic Spanning Tree Protocol (802.1D 1998) uses which sequence of variables to determine the best received BPDU?
基本的生成树协议(802.1D)，使用哪些参数来确定最佳的BPDU的包
A. 1) lowest root bridge id, 2) lowest sender bridge id, 3) lowest port id, 4) lowest root path cost B. 1) lowest root path cost, 2) lowest root bridge id, 3) lowest sender bridge id, 4) lowest sender port id C. 1) lowest root bridge id, 2) lowest sender bridge id, 3) lowest root path cost 4) lowest sender port id D. 1) lowest root bridge id, 2) lowest root path cost, 3) lowest sender bridge id, 4) lowest sender port id
Answer: D
1 最低的根桥ID 的发送者接口。
2最小的到根桥的路径 3最小的PBDU的发送者的ID 4最小的PBDU
8. Which three port states are used by RSTP 802.1w? (Choose three.)
哪三个状态出现在RSTP 802.1W中
A. Listening B. Learning C. Forwarding D. Blocking E. Discarding F. Disabled
Answer: BCE
9. Refer to the exhibit. Catalyst R is the root bridge for both VLAN 1 and VLAN 2. What is the easiest way to load-share traffic across both trunks and maintain redundancy in case a link fails, without using any type of EtherChannel link-bundling?
如图所示，在这个网络中 交换机R是vlan 1 和vlan 2 的根桥。在一条线路故障的时候用什 么最简单的办法来使通过trunk的流量有沉余，不能使用任何的EtherChannel。
A. Increase the root bridge priority (increasing the numerical priority number) for VLAN 2 on Catalyst D so that port D2 becomes the root port on Catalyst D for VLAN 2. B. Decrease the port priority on R2 for VLAN 2 on Catalyst R so that port D1 will be blocked for VLAN 2 and port D2 will remain blocked for VLAN 1. C. Decrease the path cost on R2 on Catalyst R for VLAN 2 so that port D1 will be blocked for
VLAN 2 and port D2 will remain blocked for VLAN 1. D. Increase the root bridge priority (decreasing the numerical priority number) for VLAN 2 on Catalyst R so that R2 becomes the root port on Catalyst D for VLAN 2.
Answer: B
在交换机R上减少VLAN2的优先级，使得端口D1阻塞VLAN2 ，端口D2阻塞VLAN1
10. Refer to the exhibit. In the diagram, the switches are running IEEE 802.1s MST. Which ports are in the MST blocking state?
如图所示，在这个图中，所有交换机运行IEEE802.1s MST多生成树协议，哪些接口在MST 中处于阻断的状态。
A. GE-1/2 and GE 2/1 B. GE-1/1 and GE-2/2 C. GE-3/2 and GE 4/1 D. no ports are in the blocking state
Answer: D