单项选择题 Which of the following network devices would MOST likely be installed on a network to helpreduce broadcast traffic and to allow individual virtual networks?（）

单项选择题 Users report an intermittent degradation of sound on their IP phones. Which of the following woulda network administrator do to alleviate the problem?（）

单项选择题 A technician is working on a SOHO wireless network and notices that the wireless adaptor in the laptop shows excellent connection at 11Mbps. The technician has a wireless N adaptor. Which of the following would BEST describe this connection speed?（）