Question 1

Which of the following is a set of rules designed to force the devices sharing a channel to observe orderly communications procedures?

Accepted Answer

A protocol is a set of rules governing the orderly communication between different devices sharing a channel. It helps to ensure that the devices can understand and interpret the data being exchanged between them. Framing refers to the process of dividing a data packet into smaller units for transmission, while handshaking is the process of exchanging control signals between devices to establish a connection. Public data network refers to a telecommunications network that is used to provide connectivity to the public.

Question 2

____________ occurs when calls are unable to reach their destination as a result of excess demand for system capacity.

Accepted Answer

Congestion occurs when there is excessive demand for system capacity, leading to calls being unable to reach their intended destination. Delay distortion refers to delays in signal transmission, switching involves the process of establishing a connection between two communication devices, and attenuation distortion refers to the reduction in signal strength as it travels over a medium. None of these accurately describe the scenario of calls being unable to reach their destination due to overload.

Question 3

Which of the following is the standard carrier system in North America?

Accepted Answer

T carrier system is the standard carrier system used in North America. It is a digital transmission system that uses time-division multiplexing (TDM) to transmit multiple signals over a single communication line. MUX is a generic term for several types of multiplexing techniques, E carrier is a digital transmission system used in Europe and TDMA is a multiple access technique used in wireless communication.

Question 4

A square-wave signal is a digital ______________.

Accepted Answer

A square-wave signal is a digital waveform that has a specific pattern of alternating high and low voltage levels, which is used in digital electronics for encoding binary information. It is not a circuit, transmission, or distortion.

Question 5

Who provides the switch for the frame relay network?

Accepted Answer

Commercial carriers, such as Verizon, AT&T, and Sprint, provide the switch for the frame relay network. These carriers own and operate the infrastructure needed for the network and provide the connection between the subscribing companies.

Question 6

A __________ is a packet switching network designed to carry data traffic over a public data network (PDN).

Accepted Answer

Frame relay is a packet switching network that is designed to carry data traffic over a public data network (PDN). It is a widely used WAN technology and can provide high-speed connectivity for businesses at a lower cost compared to dedicated leased lines. Trunks, local loops, and loopbacks are not specifically designed for carrying data traffic over a PDN.

Question 7

What type of effect does noise have on a signal?

Accepted Answer

Noise typically adds to the original signal, altering its intended form without necessarily amplifying or distorting its harmonic components. This is why it's considered an additive effect.

Question 8

The CSU/DSU has three alarm modes for advising the user about problems on the link. What does a blue alarm indicate?

Accepted Answer

A blue alarm indicates a total loss of incoming signal, which means that the CSU/DSU is not receiving any signal from the other end of the connection.

Question 9

What is the primary function of the private branch exchange (PBX)?

Accepted Answer

The primary function of a private branch exchange (PBX) is to switch one telephone line to another within a private organization or business, allowing for internal communication and external communication with the outside world. Option B, C, and D are not directly related to the function of a PBX.

Question 10

The connection paths for telephone service were all initially designed for what type of transmission?

Accepted Answer

The connection paths for telephone service were initially designed for voice transmission.

Question 11

What is the purpose of framing?

Accepted Answer

Framing is primarily used to maintain synchronization of the receiving equipment by separating the transmitted bit stream into discrete frames or packets. This helps the receiving equipment to identify the start and end of each data packet and ensure that the data is correctly received. Option B is related to networking protocols such as TCP/IP and is not directly related to framing. Option C is a general statement about the increasing demand for data transmission but does not relate specifically to framing. Option D refers to the process of converting a two-wire subscriber loop into a two-wire pair which is not related to framing.

Question 12

Transmission of information in a communications link is defined by three protocol techniques: half duplex,full duplex,and __________.

Accepted Answer

The two given options, half duplex and full duplex, are both examples of bidirectional communication where data can be transmitted in both directions. Simplex, on the other hand, is a unidirectional communication method where data can only flow in one direction. Asynchronous and synchronous refer to how data is transmitted in time, and are not related to the direction of data flow. Framing is a technique used to encapsulate and separate data at the physical layer and does not relate to the transmission of data in a communications link. Therefore, the correct answer is "C) simplex", which is the communication method where data can only flow in one direction.

Question 13

Which of the following do line codes enable?

Accepted Answer

Line codes enable error detection by incorporating redundancy into the transmitted data, which allows the receiver to determine if any errors have occurred during transmission. While line codes may influence traffic capacity and facilitate communication in both directions, these are not their primary functions. Traffic measurement is also not directly enabled by line codes.

Question 14

___________ involves conveying two or more information signals over a single transmission channel.

Accepted Answer

Multiplexing refers to the process of transmitting multiple signals through a single communication channel. This is done by combining different signals using a multiplexer at the sending end and sending them over a single channel. At the receiving end, a demultiplexer is used to separate the different signals and deliver them to their intended destinations. Multiplexing is commonly used in telecommunications, data communication, and digital broadcasting.

Question 15

What type of control keeps message blocks from being lost or duplicated and ensures that they are received in the proper sequence?

Accepted Answer

Sequence control keeps message blocks from being lost or duplicated and ensures that they are received in the proper sequence. Line control ensures that the data is transmitted without errors in the communication channel. Flow control manages the rate of data transmission to avoid overwhelming the recipient. Character control ensures that each character is transmitted accurately. Therefore, sequence control is the best choice to keep message blocks from being lost or duplicated and ensure their proper sequence.

Question 16

The world's public switched telephone networks,both wireline and mobile,communicate with each other by means of a signaling protocol known as __________________.

Accepted Answer

The signaling protocol used by the public switched telephone networks is Signaling System 7 (SS7). PBX refers to a private telephone system within an organization, while PSTN refers to the entire network of public telephone lines and exchanges. PDN refers to a network used for transmitting data, not specifically for telephone communication.

Question 17

Regardless of whether signals are modulated or not,what must first happen to data?

Accepted Answer

Data must first be coded in order to be transmitted or processed by any type of communication system. This involves representing the data in a standardized format, such as binary code, that can be easily interpreted by both sending and receiving devices.

Question 18

Everything facing back to the customer side from the demarc is the customer's responsibility,whereas all equipment and connections facing back toward the carrier side is the carrier's responsibility. What does this statement represent?

Accepted Answer

The statement represents the concept of demarcation point, which is the physical point where the responsibility for network communication changes from the carrier to the customer. The demarcation point is usually located at the customer premises and divides the network into two parts - the carrier side and the customer side. The point of presence refers to the location where the carrier's network equipment is located. Loopback, sequence control, and handshaking are all different networking concepts and are not related to the demarcation point or customer-carrier responsibilities.

Question 19

_____________ is (are)generated by "overlaying" on an oscilloscope all the digital bit signals received.

Accepted Answer

Eye patterns are generated by overlaying all the digital bit signals received on an oscilloscope, which helps in analyzing the quality of the signals and identifying any issues such as jitter or noise. Impedance and digital pulses are not directly related to the generation of eye patterns, and noise on the pulse is only a potential issue that can affect the quality of the signal.

Question 20

What part of the BORSCHT function applies for alerting the central office to on- and off-hook conditions?

Accepted Answer

The supervision function in BORSCHT (Battery, Overvoltage protection, Ringing, Supervision, Coding, Hybrid, Testing) is responsible for detecting the on- and off-hook conditions and alerting the central office.

Quiz 9: Telephone Networks