QUESTION 1

ADSL allocates upstream band and downstream bands of the same size.

True

False

QUESTION 2

Large numbers of voice and data transmissions can be carried simultaneously using multiplexing.

True

False

QUESTION 3

With time division multiplexing, modulation equipment is needed to move each signal to the required frequency band and multiplexing equipment is needed to combine the modulated signals.

True

False

QUESTION 4

Which kind of frame is used for initializing link, setting transfer mode, and disconnecting link?

		Information (I-frame)
		Supervisory (S-Frame)
		Unnumbered (U-frame)
		Acknkowledge (A-frame)

QUESTION 5

Which kind of frames messages include: RR, RNR, REJ, and SREJ?

		Information (I-frame)
		Supervisory (S-Frame)
		Unnumbered (U-frame)
		Acknkowledge (A-frame)

QUESTION 6

Which kind of frame is used for exchanging data (from higher layers)?

Information (I-frame)

Supervisory (S-Frame)

Unnumbered (U-frame)

Acknkowledge (A-frame)

QUESTION 7

Which kind of frame Includes piggy-backed control data?

		Information (I-frame)
		Supervisory (S-Frame)
		Unnumbered (U-frame)
		Acknkowledge (A-frame)

1 points

QUESTION 8

Which kind of frame is used only for acknowledgment of I-Frames?

		Information (I-frame)
		Supervisory (S-Frame)
		Unnumbered (U-frame)
		Acknkowledge (A-frame)

1 points

QUESTION 9

From customer to carrier is ________.

		asymmetric
		downstream
		upstream
		symmetric

1 points

QUESTION 10

To support data transfer to and from a cable modem, a cable TV provider dedicates ________ channels.

		three
		one
		two
		four

1 points

QUESTION 16

The HDLC frame has only one flag.

True

False

QUESTION 17

When optical fiber signals are multiplexed, the technique used is

		synchronous time division multiplexing
		light-source defraying
		wavelength division multiplexing
		data link control

QUESTION 18

The time it takes a message to transit a medium is called

		transmission time
		propagation time
		link management
		data link

QUESTION 19

Match the correct term with the description.

I-frames

11111111

01111110

Normal Response Mode

Stop and Wait, Go Back N, Selective Reject

A.	ARQs
B.	Broadcast
C.	Either combined station may initiate transmission without receiving permission from the other combined station.
D.	HDLC flag
E.	The primary may initiate data transfer to a secondary, but a secondary may only transmit data in response to a command from the primary.
F.	These links can carry large numbers of voice and data transmissions simultaneously.
G.	Carry the data to be transmitted for the user.
H.	Frequency Division Error Control

QUESTION 20

TDM and FDM are two forms of multiplexing which allow several transmission sources to share the capacity of a data link. Briefly describe the fundamental difference between TDM and FDM.