单项选择题
In which solution is a router ACL used?（）
A. protecting a server frome unauthorized acces B. controlling path selection,based on the route metric C. reducing router CPU utilization D. filterring packets that are passing through a router
单项选择题 Which command can be used from a PC to verfy the connectivity between host that connect through path?（）
单项选择题 What is the function of the command switchport trunk native vlan 999 on a switch?（）
单项选择题 Which IPsec security protocol should be used when confidentiality is required?（）
