单项选择题 Which of the following protocols requests membership to a multicast group?（）

单项选择题 A small amount of spoofed packets are being sent across a network and a large amount of reply packets are being sent back to the network resource. Which of the following BEST describes this security threat?（）

单项选择题 Which of the following is a hybrid network topology used for fault tolerance, in which all computersMUST connect to each other?（）