多项选择题
Which are valid modes for a switch port used as a VLAN trunk? （）
A.transparent B.auto C.on D.desirable E.blocking F.forwarding
填空题 流控的三种方式是（）、（）、（）。
多项选择题 Which two values are used by Spanning Tree Protocol to elect a root bridge (Choose two.)（）。
单项选择题 Which component of VPN technology ensures that data can be read only by its intended recipient?（）
