多项选择题
Which of the following features would BEST be used to optimize real-time voice and video chat?（）(Select TWO)
A. Load balancing B. Caching engines C. Qos D. Fault tolerance systems E. Traffic shaping
单项选择题 1000BaseT has a MAXIMUM run distance of:（）
单项选择题 Which of the following features is essential in a firewall if it is to support RTP sessions?（）
单项选择题 A layer 3 switch can move packets between subnets based on which of the following criteria?（）
