Deck 11: Network Communications

Question 1

The ringing signal voltage of the telephone service is set at:

A) 2 mV rms
B) -48VDC
C) 2V rms
D) 90V rms

Answer 1

D

Question 2

Which is not a basic mode of switching digital data?

A) circuit switching
B) packet switching
C) network switching
D) message switching

Answer 2

C

Question 3

CSMA/CD stands for:

A) Carrier Sense Multiple Access with Common DATA
B) Carrier Sense Many Applications Common Data
C) Carrier Sense Multiple Access with Collision Detection
D) None of the above

Answer 3

C

Question 4

The process of changing channels for a new cell site is called a:

A) token passing
B) tradeoff
C) handoff
D) frequency transfer

Question 5

Repeaters are used in T1 lines to carry voice channels when the lines stretch more than

A) 500 feet
B) 6,000 miles
C) 50 miles
D) 6,000 feet

Question 6

Which OSI level accepts outgoing messages and combines messages into packets, adding a header?

A) data link
B) physical
C) session
D) network
E) transport

Question 7

Which transformer allows full duplex operation by providing isolation between the transmit and receive legs of the system?

A) line hybrid
B) secondary
C) primary
D) step-up

Question 8

The voltage difference between the tip and ring lines of the phone line when it is on-hook is

A) 0V
B) 90V rms
C) 2V rms
D) 48 VDC
E) 2 mV rms

Question 9

Which OSI level is concerned with message integrity between the source and destination?

A) transport
B) presentation
C) data link
D) session
E) network

Question 10

The length of a MAC address is :

A) 6 bytes
B) 3 bytes
C) 56 bytes
D) 4 bytes

Question 11

A cable with added inductance every 6000, 4500 or 3000 feet is called a:

A) balanced cable
B) loaded cable
C) minus c cable
D) "L" cable

Question 12

The process of using the same carrier frequency in different cells that are geographically separated is known as:

A) narrowband FM bandwidth that is used
B) Rayleigh fading
C) frequency reuse
D) cell splitting

Question 13

A situation in a telephone switching office when calls are unable to reach their destination is referred to as:

A) congestion
B) delay
C) lag
D) throughput problems

Question 14

Which of the following is considered a wide area network?

A) metropolitan area network
B) open systems interconnection
C) two or more LANs connected over a wide geographical area
D) none of the above

Question 15

A circuit connecting one central office to another is

A) trunk
B) line
C) link
D) interface

Question 16

Which is not a popular topology for a local area network?

A) bus
B) star
C) broadband
D) ring

Question 17

Which OSI level is associated with handling error recovery, flow control, and sequencing?

A) session
B) physical
C) transport
D) data link
E) network

Question 18

A PBX is a:

A) Private Branch Exchange
B) Private Bit Exchange
C) Public Bit Exchange
D) Public Branch Exchange

Question 19

An integrated circuit that contains both encoding PCM circuitry and decoding PCM circuitry is known as:

A) an analog to digital converter
B) a digital to analog converter
C) a modem
D) a codec

Question 20

The FM capture effect in cellular telephone systems is hindered from minimizing co-channel interface effects due to:

A) Rayleigh fading
B) the use of frequency reuse
C) the narrowband FM bandwidth that is used
D) the cell splitting process

Question 21

What are the two systems that most mobile telephone service providers presently use? (select two)

A) CSMA/CA
B) CDMA
C) CSMA/CD
D) GSM

Question 22

A DSL service that provides 1.544 Mbps form the user to the service provider and up to 8 Mbps back to the user from the service provider is:

A) HDSL
B) IDSL
C) VDSL
D) ADSL

Question 23

A technique used by cable modems to determine the time it takes for data to travel to the cable head-end is called.

A) pinging
B) ranging
C) roaming
D) ringing

Question 24

What is the most common reason for sending a release code?

A) The circuit switch times out.
B) Someone hangs up the phone.
C) Someone places a call.
D) The trunk line is congested.

Question 25

The data rate for a (2B+D) ISDN system is:

A) 128 kbps
B) 192 kbps
C) 64 kbps
D) 144 kbps

Question 26

The V.92/90 standard for high speed modems is

A) data rate from the service provider is 56 kbps
B) data rate to the service provider is typically at V.34 speeds
C) combination of digital and analog
D) all of the above

Question 27

128.123.1.10 is an example of a:

A) class C network
B) class A network
C) class B network
D) none of the above

Question 28

The 3G wireless system supports data rates up to

A) 2 Mbps
B) 1.544 Mbps
C) 1 Mbps
D) none of the above

Question 29

The 8-pin modular connector used to connectorize CAT5/5e/6 cable is:

A) RJ-40
B) RJ-11
C) RJ-48
D) RJ-45

Question 30

Select 2 types of ISUP messages.

A) AIM
B) RTS
C) REL
D) ACM

Question 31

The protocol that has been developed to bridge the gap between mobile communications, the internet, and corporate intranets is the :

A) wireless markup language
B) wireless transmission protocol
C) wireless telephony applications
D) wireless application protocol

Question 32

For ADSL, a multi-carrier technique called is used to carry the data over the copper lines.

A) QPSK
B) Discrete multi-tone
C) Spectrum modulation
D) DPSK

Question 33

The term 100 BaseT means:

A) 100 Mbps, baseband, twisted pair
B) 100 meter, broadband, terminated
C) 100 meters, baseband twisted pair
D) none of the above

Question 34

A wireless Ethernet standard is the:

A) IEEE 802.5b
B) IEEE 802.11b
C) IEEE 802.6b
D) IEEE 802.3

Question 35

The rms voltage of a 0dBm sine wave is:

A) 2.188V
B) 0.774V
C) 1.094V
D) 1.414V

Question 36

The CSMA/CA protocol avoids collisions by

A) waiting for acknowledgement that a packet has arrived
B) using separate cables
C) limiting transmission
D) none of the above

Question 37

Setting the destination MAC address to all 1's is called a:

A) multiple delivery address
B) common address
C) router address
D) broadcast address

Question 38

A number that identifies the switch nearest to the caller is called

A) Destination Point Code
B) Release Code
C) Circuit Identification Code
D) Origination Point Code

Question 39

CDMA 2000

A) is a 21G wireless development in the United States
B) is a 2.5G wireless development in the United States
C) is a 2G wireless development in the United States
D) is a 3G wireless development in the United States

Question 40

When making a total harmonic distortion measurement of a 1kHz sinewave, the fundamental frequency of the test instrument must be set to:

A) 1 kHz
B) 2 kHz
C) 3 kHz
D) 500 kHz