Cyber/Net Chapter 3 Study Guide

_________ is the basic physical layout of the circuit.

circuit configuration

Which of the following media can best withstand harsh environmental conditions?

coaxial cable

Transmission speeds:

differ widely among media

In general, networks designed to transmit primarily computer data are likely to be ________.

digital

To get more "bandwidth" in a digital transmission, you must:

increase the range of frequencies available for a transmission

__________ is a line-of-sight type of wireless media.

microwave

A codec converts an incoming digital signal to an analog signal for transmission over an analog network.

False

Propagation delay is negligible with satellite transmission.

False

Serial mode transmission is much faster than parallel mode transmission.

False

The amount of time it takes to switch between sending and receiving in half-duplex transmission is called the propagation delay.

False

Wavelength division multiplexing can only used with copper cables.

False

The medium is the physical matter or substance that carries the voice or data transmission.

True

WDM is a version of FDM used in fiber-optic cables.

True

The height of a sound wave is called its:

amplitude

The representation of the character A by the group of 8 bits, 01000001, is an example of:

binary modulation

Which of the following would be considered a type of wireless media?

microwave

In which type of modulation is a 1 distinguished from a 0 by shifting the direction in which the wave begins?

phase modulation

_____________ refers to the difference between the original analog data and the approximation of that data using the techniques for translating from analog data to digital signals.

quantizing error

When sending four bits at a time using frequency modulation, the number of different frequency levels that would be needed would be _______.

16

If the highest frequency of a circuit is 10KHZ and the lowest frequency is 900 Hz, the bandwidth available for this circuit is :

9100 Hz

Coaxial cable costs less and offers less shielding to electrical interference than twisted pair cable.

False

Digital transmission occurs when the signal sent over the transmission media constantly varies among an infinite number of states.

False

Digital transmission produces more errors than analog transmission.

False

Guided media refers to the type of media in which the message is broadcast through the air

False

In a multipoint circuit configuration, each computer has a dedicated circuit between itself and each of the other computers in the network.

False

In simplex transmission, the data flows in both directions at the same time

False

Multimode fiber is capable of longer transmission distances than single mode fiber.

False

Multiplexing increases the cost of provisioning network circuits.

False

With modem communications, the receiving modem converts the incoming digital signal from the telephone line into an analog signal that can be understood by the computer.

False

Amplitude, frequency and phase are all characteristics of a sound wave.

True

Computers produce digital data whose values are binary: 0 or 1.

True

If each sample uses 16 bits and the number of samples taken each second is 8000; then the transmission speed on the circuit is?

128 Kbps

The typical range of human hearing is:

20 to 14,000 Hz

____________ is one of the most commonly used coding schemes used in data transmission.

ASCII

The _____________ of a circuit determines a circuit's capacity.

Bandwidth

A _________ is an FDM device that splits the physical circuit into three logical circuits (phone, upstream data, downstream data).

DSL modem

A physical circuit refers to the transmission characteristics of the connection, such as the speed at which data is being sent through the connection.

False

Which of the following is not a key advantage of digital transmission?

It permits only low transmission rates.

The acronym, Modem, stands for _________________.

Modulator/demodulator

The earliest type of fiber optic systems were:

Multimode

Which of the following statements is correct?

Serial transmission is slower than parallel transmission.

Microwave transmissions require a line of sight between any two points.

True

Of all the media available, fiber optic provides the highest transmission speeds.

True

One form of interference with satellite transmission is called raindrop attenuation in which the transmissions are absorbed by heavy rain.

True

One way to reduce quantizing errors is to increase the sampling rate of the analog signal.

True

Signal bandwidth is the difference between the highest and lowest frequencies in a band.

True

Statistical time division multiplexing does not require the capacity of the circuit to be equal to the sum of the combined circuits.

True

____________ refers to the transmission characteristics of the circuit.

logical circuit

Which of the following media has the lowest error rates and the highest transmission speeds?

fiber optic cable

The type of media usually installed on homes and businesses by the telephone company is called ____________.

twisted pair