You are the network consultant from passguide.com. Do you know what attacks are software based attacks that disable your computer and attack user by e-mail?（）

单项选择题How does a switch respond when it receives a message?（）

A.It reads the Layer-5 information and sends the message directly to the intended computer.
B.It reads the Media Access Control (MAC) address and sends the message directly to the intended computer.
C.It reads the Layer-5 information and broadcasts the message to all the computers that are connected to the switch.
D.It reads the Media Access Control (MAC) address and broadcasts the message to all the computers that are connected to the switch.

多项选择题Which two Internet Protocol (IP) telephony devices are best categorized as infrastructure components? （）

A.IP telephones
B.Voice gateways
C.Call management software
D.Media Convergence Servers (MCSs)

单项选择题What ensures that voice packets are given priority throughout the network so that conversations arrive intact?（）

A.QoS
B.Centrex
C.Packet encryption
D.Intelligent call routing

单项选择题Why is QoS important in a converged network?（）

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?（）

A.Network management
B.Network optimization
C.Network security
D.Content storage networking