_________ is one way that data rates over traditional telephone lines can be increased dramatically.

_________ is one way that data rates over traditional telephone lines can be increased dramatically.

a. SONET
b. T-carrier services
c. CSU/DSU
d. ATM
e. DSL



Answer: dsl

Digital Subscriber Line:

Digital Subscriber Line:

a. is a fairly recent approach to provide higher data transmission rates across traditional voice circuits in the local loop
b. combines analog transmission and frequency division multiplexing
c. involves the use of a customer premises equipment (CPE)
d. uses a combination of amplitude and phase modulation
e. all of the above


Answer: all of the above

Inverse multiplexing means:

Inverse multiplexing means: 

a. combining several low speed circuits to enable them to be transmitted across one high speed circuit
b. multiplexing from the terminal to the host, rather than from the host to the terminal
c. combining high speed circuits to enable them to be transmitted across one low speed circuit
d. inverting the frequencies used for transmission across a low speed circuit for switching to a digital circuit
e. multiplexing to a codec, rather than to a modem


Answer: combining several low speed circuits to enable them to be transmitted across one high speed circuit

Statistical time division multiplexers differ from time division multiplexers because they:

Statistical time division multiplexers differ from time division multiplexers because they: 

a. can cause time delays when all devices are being used for data transmission at the same time
b. take idle time of terminals into account to increase circuit throughput
c. use a complicated statistical formula to allocate time slots
d. all of the above
e. none of the above



Answer: all of the above

Which of the following types of multiplexing is least efficient for data transmission?

Which of the following types of multiplexing is least efficient for data transmission? 

a. frequency division multiplexing
b. statistical time division multiplexing
c. statistical frequency division multiplexing
d. time division multiplexing
e. wave division multiplexing



Answer: frequency division multiplexing

_____ separate channels to reduce interference between channels in frequency division multiplexing.

_____ separate channels to reduce interference between channels in frequency division multiplexing.

a. Channel blockers
b. Statistical dividers
c. Attenuators
d. Guardbands
e. Adaptive differential processors



Answer: guardbands

Frequency division multiplexing:

Frequency division multiplexing: 

a. operates by statistically time slicing the signal
b. operates by dividing the signal into different frequencies
c. uses a codec that divides signals into different channels
d. operates by time slicing the signal
e. operates by light dividing the signal


Answer: operates by dividing the signal into different frequencies