You work as a network technician at. Your boss， Mrs. ， is interested in the Spanning Tree Protocol timers. 
What can you tell her regarding the default STP timers？ （）

单项选择题A switch port on TK1 is being configured to support 802.1Q trunking.  Which of the following are true about 802.1Q trunking？（）

A.Both switches must be in the same VTP domain.
B.The encapsulation type of both ends of the trunk does not have to match.
C.The native VLAN on both ends of the trunk must be VLAN 1.
D.802.1Q trunking can only be configured on a Layer 2 port.
E.In 802.1Q trunking， all VLAN packets are tagged on the trunk link， except the native VLAN.

多项选择题WhichtwotabletypesareCEFcomponents？（）

A.forwarding information base
B.adjacency tables
C.neighbor tables
D.caching tables
E.route tables

单项选择题WhichprocessplaysamajorroleinthecreationoftheCEFadjacencytable？（）

A.Address Resolution Protocol （ARP）
B.PDU header rewrite
C.NetFlow switching
D.hello packet exchange

单项选择题Whichofthefollowingcommandscanbeissuedwithoutinterferingwiththeoperationofloopguard？（）

A.Switch（config-if）#spanning-tree guard root
B.Switch（config-if）#spanning-tree portfast
C.Switch（config-if）#switchport mode trunk
D.Switch（config-if）#switchport mode access

单项选择题A port in a redundant topology is currently in the blocking state and is not receiving BPDUs. To ensure that this port does not erroneously transition to the forwarding state，  which command should be configured to satisfy the requirement？（）

A.Switch（config）#spanning-tree loopguard default
B.Switch（config-if）#spanning-tree bdpufilter
C.Switch（config）#udld aggressive
D.Switch（config-if）#spanning-tree bpduguard