Powerpoints Telephone

Question 1

Define following:

Backplane

Answer 1

Main board where other circuits and power supplies are plugged into.

Question 2

Bandwidth:

Answer 2

Difference in Hz between ↑ and ↓ frequency of a group or band of frequencies (300Hz and 3100Hz)

Question 3

BPS:

Answer 3

Bits per second

Question 4

Buffer:

Answer 4

Storage device in a computer system that compensates for a difference in the rate data flows during transmission.

Question 5

Byte:

Answer 5

8 bits

Question 6

Bit:

Answer 6

Unit of information in binary (1+0)

Question 7

CO (Central Office):

Answer 7

Telecom facility where switching of the telephone calls is accomplished.

Question 8

COS (Class of Service):

Answer 8

Features and outside line accessible to extensions within a PBX system based on the user’s privilege level.

Question 9

CODEC:

Answer 9

Chip contained within the line unit, converts analog to digital and then uses Pulse Code Modulation (PCM).

Question 10

Cross Connect:

Answer 10

Connections between two cables on IDF or MDF.

Question 11

Flash (Hookflash):

Answer 11

Momentary depress and release a hookswitch (i.e. conference,transfer or another call)

Question 12

Frequency:

Answer 12

Number of cycles completed per units of time measured in Hertz (Hz)

Question 13

Ground Start:

Answer 13

Signaling that uses DC in a ground return path to request service.

Question 14

Hertz:

Answer 14

Unit of measurement for frequency (1 Hz = one cycle per second)

Question 15

Hookswitch:

Answer 15

Physical switch on the telephone base.

Question 16

Inside Plant:

Answer 16

Within the company or inside customer’s facility.

Question 17

ISDN (Integrated Services Digital Network)

Answer 17

Simultaneous Tx of voice and data over multiplexed communications circuits.

Question 18

Interconnect:

Answer 18

Connection between CPE (customer’s primary equipment) and public switched network.

Question 19

Intermediate Distribution Frame (IDF):

Answer 19

Extension of the MDF (main) and connected by multi-pair copper or fiber optics.

Question 20

KSU (key service units):

Answer 20

Cabinet that contains the control modules associated with key telephone systems.

Question 21

Local Exchange:

Answer 21

Switch office where outgoing/incoming calls are routed and directed to end user / end office.

Question 22

Loop:

Answer 22

“Last mile” communication path between company and subscriber’s site, referring to the two halves of a communication circuit.

Question 23

Loss:

Answer 23

Reduction of power in a circuit, measured in -dB.

Question 24

Microwave:

Answer 24

RF between 1 and 20 GHz.

Question 25

Modem: (modem/demodulator):

Answer 25

Changes digital signals into analog signals for Tx over the telephone lines.

Question 26

Macmonic: ?

Answer 26

Memory aid that helps you remember something else or an abbreviation for an operation in a computer code.

Question 27

MUX (multiplayer unit):

Answer 27

Device that contains two or more signals over the same link.

Question 28

North American Dialing Plan:

Answer 28

Area code, central office code, subscriber number (651-555-1492 example).

Question 29

Off Hook:

Answer 29

Hookswitch released, closing the tip/ring loop, signaling a request for service.

Question 30

Outside Plant:

Answer 30

Poles, cables and wires outside the company and customer's premises.

Question 31

Packet:

Answer 31

Prat of a message that has some addressing information attached.

Question 32

Packet Switching:

Answer 32

Form of multiplexing that allows decisions to be made on a packet-by-packet basis.

Question 33

Port:

Answer 33

Point of access - physical part.

Question 34

PBX (Private Branch Exchange):

Answer 34

Switching system on the customer's property for internal calling and access to outside telephone network.

Question 35

Protectors:

Answer 35

Mounted in MDF to guard outside damage to company (fuse, air gap, rare gas).

Question 36

Pulse Dialing:

Answer 36

Quick on-hook/off-hook switches (rotary dialing).

Question 37

Receiver:

Answer 37

Converts electrical energy to acoustic energy.

Question 38

Redundant System:

Answer 38

Second complete system that activates upon failure of primary system.

Question 39

RS-232:

Answer 39

Standard data input / output serial port.

Question 40

Service Request:

Answer 40

Signaling to company that dial tone and a circuit are needed.

Question 41

Signaling:

Answer 41

Exchange of control information.

Question 42

Subscriber / Number:

Answer 42

Person/Company who has telephone number registered to them (subscriber number, last four digits of telephone number).

Question 43

T1:

Answer 43

Circuit of 24 channels, channel called DSO with data rate of about 64 kbps, upload/download 1.544 Mbps.

Question 44

Transmitter:

Answer 44

Converts sound waves into electrical energy.

Question 45

Voice Frequency (Hum):

Answer 45

300-3400 Hz

Question 46

Wire Gauge (AWG)

Answer 46

↑ gauge ↓ wire, 22 to 24 AWG

Question 47

Ring Tone:

Answer 47

(+) 90-95 VAC (transmit -48VDC)

Question 48

Tip/Ring;

Answer 48

Tip - Ground (service request) | Ring - (-48 Dial tone VDCm 90-95 Ring VAC)

Question 49

Trunk:

Answer 49

Line between two switching stations (CO to CO, CO to PBX, PDX to PBX)

Question 50

The three Trunk Types and define.

Answer 50

Loop start: On hook/off hook states presence of line circuit. Ground start: Connection between PBX and CO (handshaking). Direct inward dial: One-way incoming trunk from CO; allows outside caller to dial an extension (2-7 digit extensions).

Question 51

Speech / Phone frequencies:

Answer 51

S) 100Hz - 6 kHz P) 300Hz - 3 kHz

Question 52

Inband/Outband:

Answer 52

Analog (both) - In-band: range of human hearing Out-band: Outside of human hearing

Question 53

Echo:

Answer 53

Noise that results from voice Tx, mismatches in Tx line impedance (fixed with echo canclls).

Question 54

CODEC (code/decode):

Answer 54

Analog voice converted to digital, sound depends on CODEC and sampling rate.

Question 55

Asynchronous/Synchronous Tx:

Answer 55

A) no time relation between ↑ send and receive Tx and ↓ loads faster than ↑ loads. S) Time relationship between ↑ and ↓ loads; T1 and T3 use this model.

Question 56

DSL:

Answer 56

Analog POTS circuit and data circuit on same pair; separated by frequency

Question 57

ISDN:

Answer 57

International concept whose objective is a digital telephone network.

Question 58

Digital Telephone Network

Answer 58

Not owned by anyone; end-to-end digital connection using twisted wires to connect subscriber to telco

Question 59

DSO (digital signal zero):

Answer 59

Basic unit of measure for all ISDN based technologies.

Question 60

Name ISDNs two types of channels and definition:

Answer 60

1. Bearer channel (B channel) - carries the data. | 2. Data channel (D channel) - the control channel - does not carry data.

Question 61

ISDN BRI/PRI:

Answer 61

BRI - 2 B channels and 1 D channel | PRI - 23 B channels and 1 D channel. Caller ID is Tx on the D channel.

Question 62

SS7 (signaling system 7)

Answer 62

Most widely used out-of-band signaling. Has entire OSI protocol suite attached to it.

Question 63

SS7 (signaling system 7)

Answer 63

Most widely used out-of-band signaling. Has entire OSI protocol suite attached to it.

Question 64

PBX (Private Branch of Exchange

Answer 64

Intermediate point between telephone sets and Co; Programming done remotely or locally; End user program changes in the system; Changes made via software or by moving cross connects.

Question 65

Trunks vs. Lines (PBX)

Answer 65

Trunks feed switching equipment Lines feed end devices Apply to PBX based systems.

Question 66

PBX System Capacity

Answer 66

Based on the number of trunk lines and station ports. The system is capable of: First # - Max # of trunk ports Second # - Max # of line ports. 24 x 48 = 24 trunks and 48 stations

Question 67

Cross connects:

Answer 67

Makes moves, adds and changes easier

Question 68

Hard key vs. soft key

Answer 68

Hard cannot be changed. | Soft can be changed or assigned by software.

Question 69

QoS - Quality of Service:

Answer 69

Process of prioritizing

Question 70

VoIP:

Answer 70

Sends voice over data network, converts voice signals to data. "Voice data" is prioritized over other traffic. Bypasses the Public Switched Network (PSN). Uses Session Initiation Protocol (SIP).

Question 71

T1 Circuits:

Answer 71

24 voice/data circuits, 1.544Mbsp; Requires CSU/DSU (channel/data service unit); pulse Code Modulation or Frame Relay Tx used.

Question 72

T3 Circuits:

Answer 72

672 multiplexed channels; equivalent to 28 T-1's; rate 44.736Mbps

Question 73

ISDN Circuit (BRI/PRI):

Answer 73

BRI (Basic Rate Interface) uncommon in US. Two 64kbps B channels and one 64 kbps D channel. PRI (Primary Rate Interface) 23 64kbps B channels and one 64 kbps D channel. B = bearer carries the voice signals. D = data controls info only.

Question 74

Hotline:

Answer 74

Connects two telephones together.

Question 75

Paging/Emergency Systems:

Answer 75

25 or 70v paging system.

Question 76

Paging/Emergency Systems:

Answer 76

25 or 70v paging system.