Deck 9: Digital Circuit Switch

Question 1

The digital switch provides:

A) a more efficient way to handle the many voice calls traveling through the network
B) multiple features
C) faster call processing
D) improved reliability of the communications network
E) all of the above

Answer 1

all of the above

Question 2

Global call processing, network control, signaling control, maintenance, and administration are among the responsibilities of the:

A) IC
B) NCP
C) CPS
D) trunk interface module
E) line interface module

Answer 2

CPS

Question 3

System recovery, software upgrades, storage of global routing information, distribution of information to all subsystems, and billing are among the responsibilities of the:

A) IC
B) NCP
C) CPS
D) trunk interface module
E) line interface module

Answer 3

CPS

Question 4

The interface controller interfaces directly with the subscriber line and holds translation information.

Question 5

The class ________ switch is one of the most complex digital switches in the network because it is responsible for all line-side terminations.

A) 5
B) 4
C) 3
D) 2
E) 1

Question 6

A primary ________ carrier is a long distance carrier chosen by the subscriber.

Question 7

When you pick up your telephone and hear the dial tone, you are interfacing with a class 2 switch.

Question 8

A typical class 4 switch has:

A) CPS
B) NCP
C) interface communications modules
D) trunk modules
E) all of the above

Question 9

When you pick up your telephone and dial a friend who lives across the country, your call will be routed through one or more ________ switches, which are the interface between networks and between switches.

Question 10

The class 3 switch switches trunks between:

A) toll switches
B) class 4 or 5 switches
C) international gateway switches
D) all of the above

Question 11

The class 3 toll switch and the tandem class 4 switch are very similar in physical structure except with regard to the software.

Question 12

Class 2 and class 1 switches are still very much a part of the switching hierarchy.

Question 13

Currently, the number of class 5 switches is increasing while the number of class 2 and class 1 switches is decreasing.

Question 14

The international gateway switch is used for all of the following except:

A) to switch trunks between the domestic toll network and a foreign country's telephone network
B) to convert the T1 physical interface to the European E1 physical interface
C) for signal conversion
D) none of the above (it is used for all)

Question 15

A(n) ________ switch is a small switch placed at a customer's premises to provide call switching and features.

Question 16

Speaking only in acronyms, the NPA, the NXX, and the XXXX are all codes utilized by the ________.

Question 17

Who determines the rules within a LATA?

A) ILECs
B) ROBCs
C) PUCs
D) CLECs

Question 18

The terms "wire center"and "rate center"are synonymous.

Question 19

________ occurs when two calls collide on the same trunk during call initiation.

Question 20

Which of the following is not a way of defining the trunk?

A) type of signaling used
B) one way vs. two way
C) incoming or outgoing
D) none of the above (all are ways of defining the trunk)

Question 21

________ trunks are used to connect two long distance switches (one-way or two-way) incoming or outgoing.

Question 22

The feature group D trunk:

A) charges the long distance company an access charge defined by tariffs and approved by the PUCs or PSCs
B) directs the incoming or outgoing traffic to the correct trunk leaving the access tandem
C) allows customers to choose their long distance carrier
D) all of the above

Question 23

________ calls are calls that travel between two subscribers served out of the same central office switch.

Question 24

Operator services trunks are only used when customers dial a specific code, 411 for directory assistance, or 0.

Question 25

P.01, the term used to define a 99% non-blocking rate for a switch, has to do with grade of ________.

Question 26

Which of the following is a factor contributing to call blockage?

A)too few SS-7 links
B) inadequate switch processing
C) too few trunks or circuits
D) DTMF receivers
E) all of the above

Question 27

The central premise used by mathematicians when developing traffic formulas is that callers are ________.

Question 28

Traffic models have been built around the phenomenon that every subscriber is likely to go off-hook on most holidays, during national disasters, and on Sunday afternoons.

Question 29

The difference between the Poisson and Erlang traffic models is how they expect callers to behave when they hear a fast busy signal.

Question 30

The Poisson formula:

A) expects that callers will immediately redial once they receive a fast busy tone and includes the retries in the total number of call attempts
B) assumes all calls will be cleared when blocking occurs
C) does not count all call attempts
D) does not include the blocked calls in its formula

Question 31

Average hold time is one of the hardest values to predict, due in part to the ________ revolution.

Question 32

The unit most commonly used in North America to express call volume is Erlangs, or TUs.

Question 33

Telecommunications traffic engineers are responsible for determining all of the following except:

A) the necessary size of the switch processor (BHA)
B) the number of trunks needed between two switches
C) the number of switch ports needed
D) none of the above (they are all responsibilities of telecommunications traffic engineers)

Question 34

________ in the digital circuit switch are simply software code written to instruct a switch to perform a particular task.

Question 35

Features reside in:

A) the switch
B) intelligent peripherals
C) a separate network
D) all of the above

Question 36

Call-processing features reside in a switch's ________.

Question 37

Automatic recall, calling number identification, and distinctive ringing are common ________ features.

Question 38

Why is it so important to try to build a congestion-free network?

Question 39

Discuss the process of "connecting the dots"in traffic engineering.