单项选择题
A.Because data does not need to arrive intact, so data transfer rates can be variable
B.Because lost voice-data packets must be retransmitted
C.Because voice data packets should arrive quickly and sequentially, and with no lost data
D.Because voice data packets must follow a single dedicated path through the network
单项选择题 You are the network consultant from passguide.com. Could you please tell customers what strategy will protect network resources and services from unauthorized actions?（）
单项选择题 Which network technology addresses these customer business needs: shrinking budgets and IT staffs, more complex networks, and an increased need for network security?（）
单项选择题 What does a router do?（）