What is the topology of a LAN using a router to connect several PCs in a house.
A. Star
Bus
C. Mesh
D. Ring
For switching
A. Packet swiching is more reliable than circuit swiching
B. Circuit swiching requires path setup in advance
C. Packet swich is more likely to waste bandwidth
D. Packet swiching is less efficient than circuit swiching
For Multiplexing,
A. FDM divides frequency spectrum into frequency bands
B. TDM allows mutilple signals to be transmitted on
C. the channel at the same time
D. TDM has higher efficiency than FDM
PSTN (public switched telephone network) consists:
A. Local loop, toll connecting trunk, and inter-toll trunk
B. Telephone and central office
C. Local loop, trunks, and switching office
D. Telephone, end office, and trunks
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