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Flashcards in NCT5 Deck (453):
1

The topology where signals originate in the headend andare transmitted long distances via trunk cables

Tree and Branch

2

A network architecture that typically uses fiber optic cables to bring signals to selected areas of the system called nodes

Hybrid Fiber-Coax (HFC)

3

Bi-annual tests, performed in the headend and at a number of end-of-line location

FCC Proof-of-Performance

4

The cumulative effect of return path distortions they are added to the signal at various locations in the coaxial portion of the network.

Funnel Effect

5

Specifications standards approved by the FCC in 1953for commercial analog color TV broadcasting.

National Television Standards Committee (NTSC)

6

a portion of the electromagnetic spectrum whose frequencies are well suited for transmitting and receiving Telecommunications signals through the air.

Radio Frequency (RF) Spectrum

7

Signals that flow downstream, from the headend to the network.

Forwards (Downstream) Signals

8

Signals that flow in the upstream direction, from customer to headend

Revers (upstream) Signals

9

Device that separates or combines based on frequency.

Diplex Filter

10

typical cutoff frequency for a sub-split diplex filter

About 50 MHz

11

The three major concerns/ limitations of the tree andbranch architecture are:

BandwidthImpairmentsDependency on Power

12

The lowest possible power level determined by the thermal noise generated within the electrical componentsbeing tested

Noise Floor

13

The highest power level (amplitude) reached by a carrier

Peak

14

A clustering of beats 1.25 MHz above the visual carriers in a CATV network

Composite Second Order (CSO)

15

A form of interference or noise resulting from the mixingof all of the various carriers in a CATV network

Composite Triple Beat (CTB)

16

Two major types of distortions that are typically associated with CATV

Composite Second Order (CSO) and Composite Triple Beat (CTB)

17

The 6 benefits of implementing fiber optics in broadband networks

Enhances Picture QualityIncreased ReliabilityDecreased cost of system maintenanceCost effective system bandwidth upgradesCost means of system upgrade requiring a complete change our of electronicsSmall segmented areas allow greater return path functionality

18

Having or relating to a frequency below the audibility range of the human ear.

Infrasonic

19

A stream of atomic nuclei that enter the earth’s atmosphere from outer space at speeds approaching that of light

Cosmic Rays

20

Frequency range of satellite systems

4GHz to 13GHz

21

The wavelengths most commonly used by the CATVindustry

1310nm and 1550nm

22

The type of fiber optic cable that the broadband industry uses

Single Mode Fiber

23

The process of combining multiple carriers onto a single medium

Multiplexing

24

Width of the Fiber optic core

8-10um

25

Width of the fiber optic cladding

125um

26

Width of the fiber optic coating

250um

27

Combines multiple optical signals in order to amplify them as a group and transported over a single fiber

Wave Division Multiplexing (WDM)

28

Allows multiple wavelengths above and below a centerwavelength to be carried on a single optical fiber.

Dense Wave Division Multiplexing (DWDM)

29

Three parts of the optical link

Fiber Optic CableTransmitter (Laser)Receiver (Node)

30

Individual fibers are bundled and then placed into these to reduce the possibility of damage

Buffer Tubes

31

This diode changes the RF signals to pulsesof light and then transmits them onto an optical fiber

Semiconductor Laser Diode

32

The Three types of optical transmitters that are typically used in broadband HFC Network

Fabry-Perot (F-P)Distributed Feedback (DFB)Yttrium-Aluminum-Garnet (YAG)

33

YAG

Yttrium-Aluminum-Garnet

34

DFB

Distributed Feedback

35

F-P

Fabry-Perot

36

A spare fiber installed during the construction of the network that was reserved for future use.

Dark Fiber

37

Three advantages of trunk reduction

Shorter CascadesFewer/smaller outages due to segmenting the system into smaller areasImproved picture Quality

38

FTTF

Fiber to the Feeder

39

Advantages of FTTF

Shorter CascadesFewer/smaller outages due to segmenting the system intosmaller areas.Increased Bandwidth

40

FTTC

Fiber to the Curb

41

PON

Passive Optical Network

42

Consists of a transmitter at the Headend and a receiver near the subscriber. Requires a power supply near the node but all other actives have been removed

FTTC PON

43

4 advantages of FTTC

No active devices after nodeNo CascadeFewer/smaller outages due to segmenting the system intovery small areasIncreased Bandwidth

44

A fiber-based network which uses passive splitters todeliver signals to multiple locations

Passive Optical Network (PON)

45

FTTH

Fiber to the Home

46

6 advantages of FTTH

Passive networkSingle fiber is dedicated to each subscriberFeatures local battery backup, no large remote power supplies are required.No exterior active devicesNo CascadesIncreased Bandwidth

47

This will ALWAYS be considered the "Backbone" in an HFC Network

The Fiber Network

48

A high-speed line or series of connections that forms a major pathway within a network

Backbone

49

The duplication of certain pieces and/or portions of thenetwork.

Redundancy

50

Comcast's goal for network reliability

"four-nines" or 99.99%

51

A network architecture where nodes, hubs, or headendsmay be connected with fiber optic cables to provideredundancy or increase services

Ring Architecture

52

Builds upon ring technology by adding a second (redundant) ring connecting the nodes to the headend. The second ring typically takes a different path

Ring within a Ring

53

A facility between the headend and the customer that performs many of the functions of a headend

Hubsite

54

Similar in function to a hubsite, but serving fewer customers

Optical Transition Node (OTN)

55

Usually a passive device such as a splitter or directional coupler used to combine radio frequency signals from one source with those from another

RF Combiner

56

Usually a passive device that divides a signal into two equal paths. It may be found on trunk, feeder, or drop cable.

RF Splitter

57

Device used to combine the channels for entry onto the cable or fiber optic transmitter

Headend Combiner

58

The difference, in dB, of a signal level, injected into one output port, and the measured level of that same signal on another output port, with the input port properly terminated.

Port-to-port isolation

59

Obtained by measuring the attenuation between the two output ports (A and B) when the common port (input port) is terminated in the correct value of impedance. An RF generator signal is applied to port A and an RF voltmeter reading is taken at Port B.

Isolation

60

Provision for connection to a device such as a tap, splitter, set-top box or computer

Port

61

Used to combine all of the signals to be carried over the cable system into a single medium (cable) for routing to the laser transmitters that are feeding the optical nodes in the system

Headend Combining Network

62

A measurement of the reflected signal compared to that of the incident signal

Return Loss

63

Device used to divide or combine light carriers on fiber optic cables.

Optical Splitter

64

A discontinuous signal whose various states are discrete intervals apart.

Digital Signal

65

Device used to convert an analog signal to a digital signal.

Digitizer

66

takes an amplitude measurement of the waveform at fixed intervals of time, and converts them to a binary number

Digitizer

67

The smallest unit of computerized data. Bits are defined as single characters of 0 or 1. Bandwidth is usually measured in bits-persecond.

Binary Digit (Bit)

68

A set of Bits that represent a single character. Usually there are 8 Bits in a Byte, sometimes more, depending on how the measurement is being made.

Byte

69

The number of changed states that can occur per second.

Baud

70

The value of "On" in a binary system

"1"

71

The value of "Off" in a Binary system

"0"

72

How many bits are in a "Nibble"?

4

73

If start and stop bits are included with Asynchronous Communications, then how many bits are in a byte?

10

74

ADC

Analog to Digital Conversion

75

DAC

Digital to Analog Conversion

76

A continuously varying signal with an unlimited number of possible values of amplitude and frequency.

Analog Signal

77

a non-continuous signal or carrier that changes its output in discreetly timed steps of voltage level and/or phase that can represent numerical values or other information

Digital Transmission

78

3 steps of basic ADC

SamplingQuantizationEncoding

79

The "Measuring" of the analog signal at specific intervals.

Sampling

80

The assigning of a specific value to each of the samples

Quantization

81

The process by which Quantized values are converted into a data or bit stream

Encoding

82

ASK

Amplitude Shift Keying

83

FSK

Frequency Shift Keying

84

QPSK

Quadrature Phase Shift Keying

85

QAM

Quadrature Amplitude Modulation

86

The process of varying the amplitude, frequency, or phase of a carrier to be in step with the instantaneous value of the modulating waveform

Modulation

87

Data transmission scheme wherein the carrier is shifted in amplitude

Amplitude Shift Keying (ASK)

88

The carrier frequency is shifted to represent the difference between a one and a zero

Frequency Shift Keying (FSK)

89

The position on a waveform cycle at a specific point in time. One cycle is defined as 360 degrees of this

Phase

90

Digital modulation scheme wherein the carrier is shifted in 90 degree steps. There are four possible phase states and the magnitude is constant.

Quadrature Phase Shift Keying (QPSK)

91

BPSK

BiPhase Shift Keying

92

In QPSK, what does "I" stand for?

In-Phase

93

In QPSK, what does "Q" Stand for?

Quadrature - shifted 90* or one quarter of a cycle

94

A graphic depiction of the four phase states of a Quadrature Phase Shift Key signal.

Constellation Diagram

95

What is the bandwidth of QPSK in a 6MHz bandwidth?

10 Mb/s

96

Digital modulation scheme that changes the phase and the amplitude.

Quadrature Amplitude Modulation (QAM)

97

a digital transmission technology that splits the frequency band into a number of channels. The channels are each assigned a specific time slot, so that several transmissions can share a single channel without interfering with one another

Time Division Multiple Access (TDMA)

98

The digital equivalent to Signal-to-Noise

Modulation Error Ratio (MER)

99

A joined or connected group of devices

Network

100

A network of computers linked by cable within a building or office complex.

Local Area Network (LAN)

101

A network of multiple locations linked by cable withina city or campus

Metropolitan Area Network (MAN)

102

A network typically bigger than a city or metropolitan area.

Wide Area Network (WAN)

103

A data network connects each of its endpoints to the network with a single link. A central device (hub) is used to aggregate and distribute data traffic to all endpoints and/or other central points in what’s referred to as a clustered star.

Star

104

Consists of several star networks that have been linked together

Clustered Star

105

Topology where workstations are connected to the network through a common path

Bus

106

A topology in which a data frame is passed around. As it arrives at an endpoint, the endpoint can either pass it along to the next endpoint or attach information to be sent to a destination

Token Ring

107

A network architecture where nodes, hubs, or headends may be connected with fiber optic cables to provide redundancy or increase services.

Ring

108

A method of data transmission that allows characters to be sent at irregular intervals by preceding each character with a 0 and by ending each character with a 1. This is referred to as start (0) and stop bits (1). It is the method, which most PCs use to communicate with each other and mainframes

Asynchronous Transmission

109

An extra bit added to help check if the data that isbeing transferred is correct

Parity Bit

110

The condition that occurs when two events happen in a specific time relationship with each other and both are under control of a master clock. Characters are spaced by time, not by start and stop bits.

Synchronous Transmission

111

Synchronizing bits used in synchronous transmission to maintain synchronization between transmitter and receiver.

Sync Bits

112

SNMP

Simple Network Management Protocol (SNMP)

113

NE

Network Elements

114

MIB

Management Information Base

115

A unique number assigned to a piece of equipmentused for identification purposes.

Media Access Control Address (MAC)

116

UTP

Unshielded Twisted Pair

117

signaling rate of 10BaseT

10 Mb/s

118

Signaling rate of 100BaseT

100 Mb/s

119

The designation for Ethernet over fiber optic cable, primarily for point-topoint links

10Base-F

120

This device works as a multiport signal repeater, broadcasting an incoming signal to all other ports on an ethernet network

Ethernet Hub

121

The four-part numeric address that is assigned to a computer or an account as an identification tool

Internet Protocol Address (IP)

122

DOCSIS

Data Over Cable Service Interface Specification

123

The Leading standard for cable modems

DOCSIS

124

Four devices that must be added to a system to offer high-speed internet

CMTS (Cable Modem Termination System)CM (Cable Modem)ServersNoise Filters

125

A unit consisting of various hardware and software entities that acts as the hand-off point between the RF based HFC network and other networks such as theInternet and the PSTN.

CMTS (Cable Modem Termination System)

126

Used to terminate, manage and translate high-speed Internet sessions between cable modems in a LAN and other devices in a WAN.

CMTS (Cable Modem Termination System)

127

The collection of computers accessed through the Internet. Uses a hypertext based system for finding andaccessing its resources.

WWW (World Wide Web)

128

Four Items that a CMTS manages

Time SlotsContention SlotsModem DataTransmit Levels

129

Each cable modem is assigned one of these by the CMTS and only one modem is allowed to transmit during this.

Time Slot

130

These slots are usually used for short data transmissions such as a request for an additional number of reserved time slots

Contention Slots

131

The signal level that the CMTS wants to "See"

0dBmV

132

A PC on a LAN from which information or applications are requested.

Client/Server

133

A computer circuit board (card) installed in a computer so that the computer can be connected to a network. Provide a dedicated, full-time connection to a network.

NIC (Network Interface Card)

134

Why is it called a cable "Modem"?

When they transmit data they "MOdulate" the data onto a carrier, then receive data and "DEModulate" it from the carrier and send it on to the computer

135

Four of the most common servers found in a braodband network

DHCPTODTFTPProxy

136

This server sets up the MAC and IP addresses for the cable modem.

DHCP Server(Dynamic Host Configuration Protocol)

137

This server sets up a common clock between the CM and the CMTS

TOD Server(Time of Day)

138

This server allows non-protected file transfers, such as aconfiguration file for a modem.

TFTP Server(Trivial File Transfer Protocol)

139

These servers store commonly used (or contractually stored) data. A network may have a series of these servers located in different places.

Proxy Server

140

The two types of noise filters

High Pass FilterNotch Filter

141

These types of filters only allow signals above 50MHz to pass through the filter

High Pass Filter

142

In addition to letting everything above 50 MHz to pass, this filter allows a small spectrum below 50 MHz to pass

Notch Filter

143

The process of setting up the connection between theCMTS and the cable modem, where transmit levels andfrequency are determined.

Ranged

144

A switch or collection of switches connecting multiple networks

POP (Point of Presence)

145

The point of access into theInternet.

NAP(Network Access Point)

146

The company who provides access to the Internet and the World Wide Web, who usually also provides corefeatures such as e-mail.

ISPInternet Service Provider

147

What is "7" equal to in binary?

111

148

64 QAM has how many phase angles?

52

149

16 QAM has how many phase angles?

10

150

The distance between two points of like phasein a wave.

Wavelength

151

A card made up of material similar to photographic film that changes colors when exposed to light.

Photosensitive Card

152

loss of service to ourcustomers due to a fault in thedelivery network.

Outage

153

A continuous wave (CW) frequency onto which information is modulated for transport.

Carrier Frequency

154

Maximum Bandwidth of 256QAM

42.88Mbps

155

How long must POP tests be kept at the local office?

minimum of 5 years

156

A circuit that automaticallyadjusts the gain of an amplifier sothat the output signal levels stayconstant despite varying inputlevels.

Automatic Gain Control (AGC)

157

The square root of the sum ofthe squares of the amplitudes ofindividual components of afunction, such as the frequencycomponents of a signal.

Root Mean Square (RMS)

158

What are the three type of coherent disturbances?

Composite Second Order (CSO)Composite Triple Beat (CTB)Other interfering signals (i.e. Ingress)

159

Allowable signal leakage level below 54MHz

Up to 15uV/m @ 30m

160

Allowable signal leakage level between 54MHz and 216 MHz

up to 20uV/m @ 3m

161

Allowable signal leakage above 216MHz

up to 15uV/m @30m

162

Two types of annual leakage monitoring methods

Ground BasedFlyover

163

What does a Spectrum Analyzer Display?

information in the amplitude (vertical) vs. frequency (horizontal) domain over the entire spectrum or portions of it.

164

Counteracts Horizontal forces placed on poles by the strand and cable

Guy & Anchor

165

Connects pole hardware to the anchor

Guy

166

Transfers horizontal stress from the pole to the ground

Anchor

167

Conduit pipe is usually made from

PVC

168

Allows strand to be pulled in only one direction

Strand Brake

169

Prevents unwanted payoff from the Reel

Reel Brake

170

A portable bonding method used in the stationary reel method

Traveling ground

171

Strand and cable should pay-off the _______ of the reel

Top

172

Measures pulling tension on the cable

Dynamometer

173

Ensures cables are not over tensioned

Breakaway Swivel

174

Minimizes drag on the cables in the corners & ensures that minimum bending radius is not exceeded

Corner Block

175

Tension in the cable caused by the mass of the cable & reel brake

Tail Loading

176

Cable spans______ and greater require two expansion loops

250'

177

Expansion loops should be formed on the ______ side of the pole

output

178

Double lashing is done in these three scenarios

1) two or more cables2) trunk cables3) Street and RR Crossing

179

How deep is warning tape buried?

12 inches

180

When doing a figure eight with fiber, how far apart should the cones be placed?

10-15 paces

181

Clearance for communications lines above roads, streets or alleys

15.5 ft

182

EDFA

Erbium-Doped Fiber Amplifier

183

Similar to loose tube, this type of cable has ribbons that are contained in buffer tubes

Ribbon Stranded

184

A card made up of material similar to photographic film that changes colors when exposed to light

Photosensitive Card

185

The wavelength range of visible light

390nm to 780nm

186

OCEF 

Optical Cable Entry Facility 

187

What is the formula to convert dB to mW?

mW = 10(dB/10)

188

The two means of splicing fiber optic cable

Fusion SplicingMechanical Splicing

189

APC

Angle Polish Connector

190

Monitoring Center for high-speed data and telephony.  Technical customer service calls are escalated here for investigation and network troubleshooting 

Network Operation Center (NOC) 

191

Generated during the node certification showing the fiber performance when first activated.  It is a document used to compare old test results to new test results 

Node Birth Certificate. 

192

The diameter of the glass cladding

125 microns

193

A device that scores then breaks the optical fiber to prepare it for splicing

Cleaver

194

Radiated light created in the same direction at the same time 

Coherent Light 

195

Where the connector end of the pigtail is connected to the laser.  Provides a neat and orderly method of managing the patch cords. 

Patch Panel 

196

The two ways a fusion splicer lines up the fiber ends in order to get the best possible splice.

Local Injection and Detection (LID)Profile Alignment

197

SC

Standard Connector

198

Silicon photodiodes are sensitive to light in the range of 

400 to 1000nm 

199

What is Comcast's maximum allowed loss through a fusion splice?

0.05dB

200

The ideal optical power level at a receiver input is

0dBm

201

The ratio of the velocity of light of two mediums of optical glass

Refractive Index

202

UPC

Ultra Polish Connector

203

Most light generated by lasers for telecommunications exist in this light band

Infrared band

204

Theoretically, how many wavelengths can be carried on a single fiber using DWDM?

2 to 128

205

A device used to test for dicontinuities (impedance mismatches) on coaxial cables 

Time Domain Reflectometer (TDR) 

206

Used to detect light from an optical fiber and convert the light to an electrical source

Photodiode

207

A jumper cable for optical connectors

Pigtail

208

This laser generates only one wavelength at it's output 

Distributive Feedback Laser (DFB) 

209

The ratio of the velocity of light of two mediums of optical glass 

Refractive Index 

210

Enables different wavelengths to be carried on a single optical fiber

WDM (Wave Division Multiplexing)

211

List the 5 laser classes

Class 1Class 2/2AClass 3AClass 3BClass 4

212

Typical loss (in dB) of a fiber connector

0.5dB

213

A device used to wrap and store excess fiber optic cable in an aerial location

Snowshoe

214

Two types of fiber amplifiers

EDFA (Erbium-Doped Fiber Amplifier)YEDFA (Ytterbium Erbium-Doped Fiber Amplifier)

215

Formula to convert mW to dBm

dBm = 10log(mW)

216

An electronic or optical process that combines several individual signals or wavelengths into a single carrier or path.

Multiplexing

217

Type of cable consisting of larger buffer tubes with the fibers inside, surrounded by fiberglass water block tape, armor, two steel strength members and a jacket

Unitube

218

a trillion Hertz or 1,000 gighertz

Terahertz

219

Similar to loose tube, this type of cable consists of buffer tubes surrounded by a fiberglass wrap and two steel strength members on each side molded into the jacket.

Flex Tube

220

The most basic laser and consists of two pieces of semiconductor material with an active layer between them 

Fabry-Perot Laser 

221

Central data point communicating with endpoints of a network.  All data communications must flow through the central point. 

Star

222

Test equipment used to visually see the losses, breaks and distance measurements in an optical fiber

OTDR (Optical Time Domain Reflectometer)

223

Fiber loss is expressed in this manner

dB/km (decibels per kilometer)

224

A network of devices connected together in a circular communication link

Ring 

225

A board for making optical connections consisting of sleeves used to line up two connectors

Patch Panel

226

Used to measure transmitter outputs and receiver inputs

Optical Power Meter

227

Allows multiple wavelengths above and below a center wavelength to be carried on a single optical fiber

DWDM (Dense Wave Division Multiplexing)

228

Output of a YEDFA 

22dBm 

229

How far back should the fibers be stripped?

1-1/2 to 2 inches

230

Typical loss (in dB) of a mechanical splice

0.25dB

231

Allows only a single mode of light to propagate through the fiber core

Single Mode Fiber

232

Light that is reflected back to the source and contributes to the optical fiber loss 

Backscattered Light 

233

A special optical fiber connector used in gigabit Ethernet Devices that uses fibers in pairs with LC and/or SC.

LCSC

234

A connection point in a cable system where a fiber enters a neighborhood and the optical signal is converted to an electrical signal

Node

235

How many feet is equal to 1km

3300 ft

236

Is a water-resistant enclosure that is intended for storing trays of optical fiber splices between incoming outside plant fiber cables and the inside fiber cables going to the fiber patch panels. 

OCEF (Optical Cable Entry Facility) 

237

This cable configuration is the same as unitube, except fibers are arranged side by side

Ribbon

238

FC

Ferruled Connector

239

Attenuation of the wavelength 1310nm per kilometer

.35 dB/km

240

Method of joining two optical fibers of the same type using an electrical arc to form a precision splice

Fusion Splice

241

YEDFA

Ytterbium Erbium-Doped Fiber Amplifier

242

The twelve fiber and buffer tube colors in order:


* Blue
* Orange
* Green
* Brown
* Slate
* White
* Red
* Black
* Yellow
* Violet
* Rose
* Aqua

243

The three most important procedures to insure a good splice

Proper CleaningProper CleaveControlled Break

244

This is the sum of all the losses associated with a fiber link between the optical fiber transmitter and the optical fiber receiver

Loss Budget

245

5 types of fiber connections

FC (Ferruled Connector)SC (Standard Connector)UPC (Ultra Polish Connector)APC (Angle Polish Connector)LCSC

246

Output gain of an EDFA 

Over 40dB Possible 

247

Used to visually see the losses, breaks and distance measurements in an optical fiber link 

OTDR (Optical Time Domain Reflectometer) 

248

One billion cycles per second or 1 billion Hertz

Gigahertz

249

In DWDM, the wavelengths are this far apart

0.8nm or 100GHz

250

Attenuation of the wavelength 1550nm per kilometer

.25 dB/km

251

Color-Coded tubes that house and protect the optical fibers within a fiber optic cable.

Buffer Tubes

252

A method used to lock and mark one end of a line in order to allow someone to safely work on the other end

Lockout Tag-out

253

Typical loss (in dB) of a fusion splice

0.1dB

254

The distance that cannot be seen by the OTDR because the initial pulse doesn't create enough backscattered light and "hides" the first several hundred feet of cable. 

Dead Zone 

255

The preferred method of fiber optic splicing

Fusion Splicing

256

This type of fiber optic cable consists of a single strength member in the center surrounded by color-coded buffer tubers, which contain fibers that are also color-coded.

Loose Tube

257

A temporary joining of two optical fibers of the same type using a plastic form to hold and lock fibers together.

Mechanical Splice

258

The gel from buffer tubes should be cleaned with what?

Isopropyl Alcohol that is at least 90% pure

259

To prevent stress on the fiber, cable manufacturers put about 1% more fiber in the cable than the length of the cable itself, to allow for some stretch.  What is this called? 

Lay Loss Factor 

260

Used to locate faults in jumpers and pigtails

Visible fault locator

261

A Photodiode used to detect light from an optical fiber and converts the light to an electrical source

PIN Diode 

262

The interface between the Headend (Hub) and the RF Plant.

Node

263

Optical fiber with erbium, a rare earth material, added to the glass during the manufacturing process, to give fiber useful properties when properly lased 

Doping 

264

Attaches optical fiber from the device to an optical connector 

Pigtail 

265

The difference between transmitted and received power resulting from the loss through equipment, lines, or other transmission devices; usually expressed in decibels

Attenuation

266

The diameter of the fiber optic coating

250 microns

267

Allows many modes of light to propagate through the core.

Multi-Mode Fiber

268

Name the 5 most common fiber optic cable arrangements

Loose TubeFlex TubeUnitubeRibbonRibbon Stranded

269

A cabinet or rack that houses the splices of the outside plant fiber to the inside headend, node or OTN fiber. 

Splice Panel 

270

The diameter range of the fiber optic core

8 to 10 micron

271

Extra fiber connected to the OTDR to make up for the dead zone. 

Launch Cable 

272

What does LASER stand for?

Light Amplification by the Stimulated Emission of Radiation

273

Optical splitter loss is based on _________

Percentages

274

Fiber amplifier that provides the greatest output gain

YEDFA (Ytterbium Erbium-Doped Fiber Amplifier)

275

Advantage of InGaAs over Ge detectors. 

InGaAs are less noisy and allow measurements down to -65dBm. 

276

Fibers are contained in a plastic tube much larger than the optical fibers.  The fibers can move freely within the tube.

Loose Tube

277

A photo diode used to detect light from an optical fiber and convert the light to an electrical source

PIN Diode

278

The topology where signals originate in the headend andare transmitted long distances via trunk cables

Tree and Branch

279

A network architecture that typically uses fiber optic cables to bring signals to selected areas of the system called nodes

Hybrid Fiber-Coax (HFC)

280

Bi-annual tests, performed in the headend and at a number of end-of-line location

FCC Proof-of-Performance

281

The cumulative effect of return path distortions they are added to the signal at various locations in the coaxial portion of the network.

Funnel Effect

282

Specifications standards approved by the FCC in 1953for commercial analog color TV broadcasting.

National Television Standards Committee (NTSC)

283

a portion of the electromagnetic spectrum whose frequencies are well suited for transmitting and receiving Telecommunications signals through the air.

Radio Frequency (RF) Spectrum

284

Signals that flow downstream, from the headend to the network.

Forwards (Downstream) Signals

285

Signals that flow in the upstream direction, from customer to headend

Revers (upstream) Signals

286

Device that separates or combines based on frequency.

Diplex Filter

287

typical cutoff frequency for a sub-split diplex filter

About 50 MHz

288

The three major concerns/ limitations of the tree andbranch architecture are:

BandwidthImpairmentsDependency on Power

289

The lowest possible power level determined by the thermal noise generated within the electrical componentsbeing tested

Noise Floor

290

The highest power level (amplitude) reached by a carrier

Peak

291

A clustering of beats 1.25 MHz above the visual carriers in a CATV network

Composite Second Order (CSO)

292

A form of interference or noise resulting from the mixingof all of the various carriers in a CATV network

Composite Triple Beat (CTB)

293

Two major types of distortions that are typically associated with CATV

Composite Second Order (CSO) and Composite Triple Beat (CTB)

294

The 6 benefits of implementing fiber optics in broadband networks

Enhances Picture QualityIncreased ReliabilityDecreased cost of system maintenanceCost effective system bandwidth upgradesCost means of system upgrade requiring a complete change our of electronicsSmall segmented areas allow greater return path functionality

295

Having or relating to a frequency below the audibility range of the human ear.

Infrasonic

296

A stream of atomic nuclei that enter the earth’s atmosphere from outer space at speeds approaching that of light

Cosmic Rays

297

Frequency range of satellite systems

4GHz to 13GHz

298

The wavelengths most commonly used by the CATVindustry

1310nm and 1550nm

299

The type of fiber optic cable that the broadband industry uses

Single Mode Fiber

300

The process of combining multiple carriers onto a single medium

Multiplexing

301

Width of the Fiber optic core

8-10um

302

Width of the fiber optic cladding

125um

303

Width of the fiber optic coating

250um

304

Combines multiple optical signals in order to amplify them as a group and transported over a single fiber

Wave Division Multiplexing (WDM)

305

Allows multiple wavelengths above and below a centerwavelength to be carried on a single optical fiber.

Dense Wave Division Multiplexing (DWDM)

306

Three parts of the optical link

Fiber Optic CableTransmitter (Laser)Receiver (Node)

307

Individual fibers are bundled and then placed into these to reduce the possibility of damage

Buffer Tubes

308

This diode changes the RF signals to pulsesof light and then transmits them onto an optical fiber

Semiconductor Laser Diode

309

The Three types of optical transmitters that are typically used in broadband HFC Network

Fabry-Perot (F-P)Distributed Feedback (DFB)Yttrium-Aluminum-Garnet (YAG)

310

YAG

Yttrium-Aluminum-Garnet

311

DFB

Distributed Feedback

312

F-P

Fabry-Perot

313

A spare fiber installed during the construction of the network that was reserved for future use.

Dark Fiber

314

Three advantages of trunk reduction

Shorter CascadesFewer/smaller outages due to segmenting the system into smaller areasImproved picture Quality

315

FTTF

Fiber to the Feeder

316

Advantages of FTTF

Shorter CascadesFewer/smaller outages due to segmenting the system intosmaller areas.Increased Bandwidth

317

FTTC

Fiber to the Curb

318

PON

Passive Optical Network

319

Consists of a transmitter at the Headend and a receiver near the subscriber. Requires a power supply near the node but all other actives have been removed

FTTC PON

320

4 advantages of FTTC

No active devices after nodeNo CascadeFewer/smaller outages due to segmenting the system intovery small areasIncreased Bandwidth

321

A fiber-based network which uses passive splitters todeliver signals to multiple locations

Passive Optical Network (PON)

322

FTTH

Fiber to the Home

323

6 advantages of FTTH

Passive networkSingle fiber is dedicated to each subscriberFeatures local battery backup, no large remote power supplies are required.No exterior active devicesNo CascadesIncreased Bandwidth

324

This will ALWAYS be considered the "Backbone" in an HFC Network

The Fiber Network

325

A high-speed line or series of connections that forms a major pathway within a network

Backbone

326

The duplication of certain pieces and/or portions of thenetwork.

Redundancy

327

Comcast's goal for network reliability

"four-nines" or 99.99%

328

A network architecture where nodes, hubs, or headendsmay be connected with fiber optic cables to provideredundancy or increase services

Ring Architecture

329

Builds upon ring technology by adding a second (redundant) ring connecting the nodes to the headend. The second ring typically takes a different path

Ring within a Ring

330

A facility between the headend and the customer that performs many of the functions of a headend

Hubsite

331

Similar in function to a hubsite, but serving fewer customers

Optical Transition Node (OTN)

332

Usually a passive device such as a splitter or directional coupler used to combine radio frequency signals from one source with those from another

RF Combiner

333

Usually a passive device that divides a signal into two equal paths. It may be found on trunk, feeder, or drop cable.

RF Splitter

334

Device used to combine the channels for entry onto the cable or fiber optic transmitter

Headend Combiner

335

The difference, in dB, of a signal level, injected into one output port, and the measured level of that same signal on another output port, with the input port properly terminated.

Port-to-port isolation

336

Obtained by measuring the attenuation between the two output ports (A and B) when the common port (input port) is terminated in the correct value of impedance. An RF generator signal is applied to port A and an RF voltmeter reading is taken at Port B.

Isolation

337

Provision for connection to a device such as a tap, splitter, set-top box or computer

Port

338

Used to combine all of the signals to be carried over the cable system into a single medium (cable) for routing to the laser transmitters that are feeding the optical nodes in the system

Headend Combining Network

339

A measurement of the reflected signal compared to that of the incident signal

Return Loss

340

Device used to divide or combine light carriers on fiber optic cables.

Optical Splitter

341

A discontinuous signal whose various states are discrete intervals apart.

Digital Signal

342

Device used to convert an analog signal to a digital signal.

Digitizer

343

takes an amplitude measurement of the waveform at fixed intervals of time, and converts them to a binary number

Digitizer

344

The smallest unit of computerized data. Bits are defined as single characters of 0 or 1. Bandwidth is usually measured in bits-persecond.

Binary Digit (Bit)

345

A set of Bits that represent a single character. Usually there are 8 Bits in a Byte, sometimes more, depending on how the measurement is being made.

Byte

346

The number of changed states that can occur per second.

Baud

347

The value of "On" in a binary system

"1"

348

The value of "Off" in a Binary system

"0"

349

How many bits are in a "Nibble"?

4

350

If start and stop bits are included with Asynchronous Communications, then how many bits are in a byte?

10

351

ADC

Analog to Digital Conversion

352

DAC

Digital to Analog Conversion

353

A continuously varying signal with an unlimited number of possible values of amplitude and frequency.

Analog Signal

354

a non-continuous signal or carrier that changes its output in discreetly timed steps of voltage level and/or phase that can represent numerical values or other information

Digital Transmission

355

3 steps of basic ADC

SamplingQuantizationEncoding

356

The "Measuring" of the analog signal at specific intervals.

Sampling

357

The assigning of a specific value to each of the samples

Quantization

358

The process by which Quantized values are converted into a data or bit stream

Encoding

359

ASK

Amplitude Shift Keying

360

FSK

Frequency Shift Keying

361

QPSK

Quadrature Phase Shift Keying

362

QAM

Quadrature Amplitude Modulation

363

The process of varying the amplitude, frequency, or phase of a carrier to be in step with the instantaneous value of the modulating waveform

Modulation

364

Data transmission scheme wherein the carrier is shifted in amplitude

Amplitude Shift Keying (ASK)

365

The carrier frequency is shifted to represent the difference between a one and a zero

Frequency Shift Keying (FSK)

366

The position on a waveform cycle at a specific point in time. One cycle is defined as 360 degrees of this

Phase

367

Digital modulation scheme wherein the carrier is shifted in 90 degree steps. There are four possible phase states and the magnitude is constant.

Quadrature Phase Shift Keying (QPSK)

368

BPSK

BiPhase Shift Keying

369

In QPSK, what does "I" stand for?

In-Phase

370

In QPSK, what does "Q" Stand for?

Quadrature - shifted 90* or one quarter of a cycle

371

A graphic depiction of the four phase states of a Quadrature Phase Shift Key signal.

Constellation Diagram

372

What is the bandwidth of QPSK in a 6MHz bandwidth?

10 Mb/s

373

Digital modulation scheme that changes the phase and the amplitude.

Quadrature Amplitude Modulation (QAM)

374

a digital transmission technology that splits the frequency band into a number of channels. The channels are each assigned a specific time slot, so that several transmissions can share a single channel without interfering with one another

Time Division Multiple Access (TDMA)

375

The digital equivalent to Signal-to-Noise

Modulation Error Ratio (MER)

376

A joined or connected group of devices

Network

377

A network of computers linked by cable within a building or office complex.

Local Area Network (LAN)

378

A network of multiple locations linked by cable withina city or campus

Metropolitan Area Network (MAN)

379

A network typically bigger than a city or metropolitan area.

Wide Area Network (WAN)

380

A data network connects each of its endpoints to the network with a single link. A central device (hub) is used to aggregate and distribute data traffic to all endpoints and/or other central points in what’s referred to as a clustered star.

Star

381

Consists of several star networks that have been linked together

Clustered Star

382

Topology where workstations are connected to the network through a common path

Bus

383

A topology in which a data frame is passed around. As it arrives at an endpoint, the endpoint can either pass it along to the next endpoint or attach information to be sent to a destination

Token Ring

384

A network architecture where nodes, hubs, or headends may be connected with fiber optic cables to provide redundancy or increase services.

Ring

385

A method of data transmission that allows characters to be sent at irregular intervals by preceding each character with a 0 and by ending each character with a 1. This is referred to as start (0) and stop bits (1). It is the method, which most PCs use to communicate with each other and mainframes

Asynchronous Transmission

386

An extra bit added to help check if the data that isbeing transferred is correct

Parity Bit

387

The condition that occurs when two events happen in a specific time relationship with each other and both are under control of a master clock. Characters are spaced by time, not by start and stop bits.

Synchronous Transmission

388

Synchronizing bits used in synchronous transmission to maintain synchronization between transmitter and receiver.

Sync Bits

389

SNMP

Simple Network Management Protocol (SNMP)

390

NE

Network Elements

391

MIB

Management Information Base

392

A unique number assigned to a piece of equipmentused for identification purposes.

Media Access Control Address (MAC)

393

UTP

Unshielded Twisted Pair

394

signaling rate of 10BaseT

10 Mb/s

395

Signaling rate of 100BaseT

100 Mb/s

396

The designation for Ethernet over fiber optic cable, primarily for point-topoint links

10Base-F

397

This device works as a multiport signal repeater, broadcasting an incoming signal to all other ports on an ethernet network

Ethernet Hub

398

The four-part numeric address that is assigned to a computer or an account as an identification tool

Internet Protocol Address (IP)

399

DOCSIS

Data Over Cable Service Interface Specification

400

The Leading standard for cable modems

DOCSIS

401

Four devices that must be added to a system to offer high-speed internet

CMTS (Cable Modem Termination System)CM (Cable Modem)ServersNoise Filters

402

A unit consisting of various hardware and software entities that acts as the hand-off point between the RF based HFC network and other networks such as theInternet and the PSTN.

CMTS (Cable Modem Termination System)

403

Used to terminate, manage and translate high-speed Internet sessions between cable modems in a LAN and other devices in a WAN.

CMTS (Cable Modem Termination System)

404

The collection of computers accessed through the Internet. Uses a hypertext based system for finding andaccessing its resources.

WWW (World Wide Web)

405

Four Items that a CMTS manages

Time SlotsContention SlotsModem DataTransmit Levels

406

Each cable modem is assigned one of these by the CMTS and only one modem is allowed to transmit during this.

Time Slot

407

These slots are usually used for short data transmissions such as a request for an additional number of reserved time slots

Contention Slots

408

The signal level that the CMTS wants to "See"

0dBmV

409

A PC on a LAN from which information or applications are requested.

Client/Server

410

A computer circuit board (card) installed in a computer so that the computer can be connected to a network. Provide a dedicated, full-time connection to a network.

NIC (Network Interface Card)

411

Why is it called a cable "Modem"?

When they transmit data they "MOdulate" the data onto a carrier, then receive data and "DEModulate" it from the carrier and send it on to the computer

412

Four of the most common servers found in a braodband network

DHCPTODTFTPProxy

413

This server sets up the MAC and IP addresses for the cable modem.

DHCP Server(Dynamic Host Configuration Protocol)

414

This server sets up a common clock between the CM and the CMTS

TOD Server(Time of Day)

415

This server allows non-protected file transfers, such as aconfiguration file for a modem.

TFTP Server(Trivial File Transfer Protocol)

416

These servers store commonly used (or contractually stored) data. A network may have a series of these servers located in different places.

Proxy Server

417

The two types of noise filters

High Pass FilterNotch Filter

418

These types of filters only allow signals above 50MHz to pass through the filter

High Pass Filter

419

In addition to letting everything above 50 MHz to pass, this filter allows a small spectrum below 50 MHz to pass

Notch Filter

420

The process of setting up the connection between theCMTS and the cable modem, where transmit levels andfrequency are determined.

Ranged

421

A switch or collection of switches connecting multiple networks

POP (Point of Presence)

422

The point of access into theInternet.

NAP(Network Access Point)

423

The company who provides access to the Internet and the World Wide Web, who usually also provides corefeatures such as e-mail.

ISPInternet Service Provider

424

The local, long-distance and internationalphone system in use today

PSTN(Public Switched Telephone Network)

425

This device in the Headend controls the operation of CDV.

HDT(Host Digital Terminal)

426

What is "7" equal to in binary?

0111

427

64 QAM has how many phase angles?

52

428

16 QAM has how many phase angles?

10

429

The distance between two points of like phasein a wave.

Wavelength

430

A card made up of material similar to photographic film that changes colors when exposed to light.

Photosensitive Card

431

ANSI Laser standard that separates lasers into various classes that take into consideration the operating wavelength, output power level and whether the laser operates as a continuous or pulsed light output

Z-136

432

loss of service to ourcustomers due to a fault in thedelivery network.

Outage

433

A continuous wave (CW) frequency onto which information is modulated for transport.

Carrier Frequency

434

Maximum Bandwidth of 256QAM

42.88Mbps

435

How long must POP tests be kept at the local office?

minimum of 5 years

436

A circuit that automaticallyadjusts the gain of an amplifier sothat the output signal levels stayconstant despite varying inputlevels.

Automatic Gain Control (AGC)

437

The square root of the sum ofthe squares of the amplitudes ofindividual components of afunction, such as the frequencycomponents of a signal.

Root Mean Square (RMS)

438

What are the three type of coherent disturbances?

Composite Second Order (CSO)Composite Triple Beat (CTB)Other interfering signals (i.e. Ingress)

439

FCC requirement for isolation

18dB

440

Allowable signal leakage level below 54MHz

Up to 15uV/m @ 30m

441

Allowable signal leakage level between 54MHz and 216 MHz

up to 20uV/m @ 3m

442

Allowable signal leakage above 216MHz

up to 15uV/m @30m

443

The two types of leakage monitoring frequency.

Continuous MonitoringQuarterly Monitoring

444

Two types of annual leakage monitoring methods

Ground BasedFlyover

445

What leaks are included in the CLI calculation?

All leaks 50uV or greater

446

what is the elevation that a flyover is completed at? (in meters)

450m(1476')

447

Two requirements for monitoring of plant with a handheld signal leakage detector

-Must be properly calibrated to detect a leak of 20uV/m or greater @ 3m-Perform all measurements with a horizontally polarized dipole antenna, preferably located no more than 3m from the leak and 3m from the ground

448

What does a Spectrum Analyzer Display?

information in the amplitude (vertical) vs. frequency (horizontal) domain over the entire spectrum or portions of it.

449

comparable in certain respects, typically in a way that makes clearer the nature of the things compared.

Analogous

450

states that in order to obtain an accurate recreation of a signal, it must be sampled at a rate of at least twice the highest frequency

Nyquist's Rule

451

In identifying utility locate colors, What colors represent power, telecommunications, and water?

Red, Orange, and Blue

452

How many feet should a ladder be angled per 4 feet of height?

1 foot

453

When a ladder is extended to 20 feet, how far from the base of the pole should its feet be positioned?

5 feet