多项选择题 A new switch is installed in the Testking network. This switch is to be configured sothat VLAN information will be automatically distributed to all the other Cisco Catalyst switches in the network. Which of the conditions below have to be met in order for this to occur?（）

单项选择题 Which switching mode provides the highest level of integrity and error-free transport, rather then maximizing speed?（）

单项选择题 A network administrator wants to control which user hosts can access the network based on their MAC address. What will prevent workstations with unauthorized MAC addresses from connecting to the network through a switch?（）