ct3 Flashcards
Aspect ratio of HDTV
16:9
Preferred method of coax cable routing
Home Run
What is CRT?
cathode ray tube
What four services are business class TV customers not eligible to receive?
PPVVODDVRPremium channels
What does REN stand for?
Ring equivalency number
How much REN do we suppoprt?
5
DOCSIS
Data Over Cable Services Interface Specification
What ensures interoperability of cable modems from various manufacturers?
DOCSIS
What does MoCA stand for?
Multimedia over Coax Alliance
Name four COMCAST business services
TVPhoneInternetTeleworker
What is the delay between transmission and arrival of a packet?
latency
What is it called when packets are received in the wrong order?
jitter
In general, business customers sign a __ to __ year contract.
2 to 5
What does the term POTS mean?
Plain Old Telephone System
What is the name of the dial tone a customer will hear when they have voicemail?
stutter
what does CMTS stand for?
Cable Modem Termination System
How many pairs should there be in a fax machine flat satin?
1 pair
What does EDTV stand for?
Enhanced Definition TV
What is the resolution of EDTV?
480p
What does eMTA stand for?
embedded mutimedia terminal adapter
All lights flashing on an eMTA indicate what type of problem?
Foreign Voltage
What does VOIP stand for?
Voice Over Internet Protocol
List the 3 pairs in order of older station wire?
Green/Red Black/Yellow White/Blue
What tools can you use to check polarity on a phone line?
Butt Set and Toner
Internet phone services transmit calls over a ______ network.
Public
What is the supervisory voltage provided by an eMTA?
48 VDC
What connection type provides both audio and video?
HDMI
Out of the following colors: Green/Red Yellow/Black list the tip and ring.
green-tipred-ringyellow-ringblack-tip
What is DHCP?
Dynamic Host Configuration Protocol
What is QAM?
Quadrature Amplitude Modulation
What frequencies are assigned to the downstream and upstream?
Up- 5-42 MhzDown- 54-1000 Mhz
List 2 types of call forwarding.
SelectiveVariable
What is the 4 step troubleshooting process?
IdentifyIsolateRepairVerify
What are 3 ways to access voicemail?
*99Xfinity ConnectVM Access
What is ICFR?
In Channel Frequency Response
Ring voltage for CDV?
60-90 V AC
5 factors of attenuation
Diameter of center conductorDielectricFrequencyTemperatureLength of cable
What is the difference between dB and dBmV?
dB is relativedBmV is absolute
Multiple carriers oscillating at different frequencies transported in the same medium is what?
Frequency Division Multiplexing
Passage of outside signal into the cable is known as what?
Ingress
Signal leaking out of the system is known as what?
Egress
What are the three main components of a home theater system?
AudioVideoEnvironment
List the 4 main types of displays
Direct viewRear ProjectionFront projectionFlat Panel
Latent or out of sync audio is known as?
Lip sync
MPEG identifies and removes what type of information between successive frames of the picture?
Redundant / Static
Separating successive frames into two types of video information is also known as what?
compression
What is a rugged, inexpensive to repair bandwidth versatile transmission medium?
Coaxial cable
A home run system is also known as what?
Star topology
Formula for voltage
E=IxR
What does DLNA stand for?
Digital Living Network Alliance
What are the 3 troubleshooting areas in CDV?
Before eMTAAt eMTAAfter eMTA
What numbers do you need to dial in order to place an international call?
011 + country code
DHCP
Dynamic Host Configuration Protocol
What is the measure of voice, data and or video quality provided to a customer called?
Quality of Service (QoS)
What is our loop current?
23-40 mA
List 2 safety precautions to take before working on phone lines.
Disconnect ILECDisconnect eMTA
When an eMTA is upgrading firmware what lights are flashing?
U/S and D/S
If the power light is flashing on an eMTA it indicates what?
AC power failure
What tool can you use to connect your butt set to a modular outlet?
banjo
The twists in CAT5 wire help to prevent these 2 things?
crosstalknoise
What type of cable is needed to backfeed an eMTA to a wallplate?
electrically straight
Excess debris left in a punch down block that can cause a short is known as?
shiners
ILEC
Incumbent Local Exchange Carrier
What defines where COMCAST may physically disconnect a customer from the ILEC network?
Interconnection Agreement
When troubleshooting a data device what is the first thing you should check?
dial tone and polarity
What must be placed between the eMTA and the customers telephones if they have an alarm system?
RJ31X
Businesses can add what services a la carte?
HDMusic ChoiceMulti LatinoSports Packages
What is an internet product for companies that have a mobile workforce?
Teleworker
How many email addresses are available to a teleworker customer?
7
How would a teleworker customer add or disconnect accounts?
Teleworker order center
What DOCSIS standard brought about channel bonding and IPv6?
DOCSIS 3.0
What is DNS and what does it do?
Domain Name SystemTranslates the FQDN to an IP
Connect RF to power in order to prevent what?
Ranging
The cumulative effect of ingress from multiple homes is known as what?
Funnel effect
The number one cause of ingress and egress occurs where in the system?
Drop system
The number 1 cause of ingress and egress?
Poorly installed connectors
CPE
Customer Premise Equipment
A return path problem that is caused by the corrosion of dissimilar metals?
CPD
What audio format has 4 channels: Left, Right, Center, Surrounds
Dolby Pro Logic
3 types of audio formats with 5.1 channels.
DTS Neo:6Dolby DigitalDTS
What essential supplies are needed for an Xfinity Internet installation?
Modem, cable installation materials (coaxial cable and splitters), welcome kits, ethernet cables
What are the installation options for Xfinity Internet?
Self installation and professional installation
What should the work order contain prior to installation?
Customer’s name and address, account number, current comcast services, information specific to the order, modem information (including correct rate codes for modem installation), comcast.net username
What essential supplies are needed for an Xfinity Internet installation?
Modem, cable installation materials (coaxial cable and splitters), welcome kits, ethernet cables
What is a bit?
a single character of data
What is a Byte (B)?
8 bits, a larger amount of data but still not very large.
What is a Kilobit (Kb)?
Roughly 1000 bits. Many Internet applications measure speed in kilobits
What is a Gigabyte (GB)?
Roughly one thousand megabytes. Gigabytes are common when talking about hard drive storage.
What is a Megabit (Mb)?
Roughly one million bits. This is smaller than a megabyte, but is a common measurement for network bandwidth.
Projects light from microscopic mirrors onto big, widescreen, rear-projection TVs (or micro-displays)
Digital Light Processing(DLP)
What is the Pre-installation internet requirement to installing a CT3 cablecard in a PC?
An Internet connection MUST BE working prior to installation.
Boosts low level signals from the components to the speakers.
Amplifier
Images result when electrically charged gases illuminate colored phosphors
Plasma
What type of cable fulfills the video requirement for an internal or external xfinity TV user?
A/B USB cable.
What is a Gigabyte (GB)?
Roughly one thousand megabytes. Gigabytes are common when talking about hard drive storage.
Includes audio and video input/output ports; Audio input to AV receivers internal preamplifier; Audio output fed to system speakers; Video for selected device is fed from the receivers output jacks to connected video display
Audio/Video Receiver
What is the requirement PRIOR to installing a CT3 cablecard in a PC?
An Internet connection MUST BE working prior to installation.
Toslink or EIA-J are types of what?
Optical Digital Audio connectors
Uses an RCA connector to carry Digital Audio
Coaxial Digital connection
Uses an RCA connector to Analog Audio
Stereo Connection
Creates a picture by shooting an electronic beam at a phosphor-coated glass screen
Cathode Ray Tube (CRT)
Creates images by passing light through a layer of liquid crystal sandwiched between two panes of polarized glass.
Liquid Crystal Display(LCD)
Allows customers to link home TVs from any PC or hand-held device
Slingbox
Uses LED backlighting instead of the cold cathode fluorescents CCFL
LED-backlit LCD
A general term for non-projection types of TVs, which include conventional tube TVs and flat-panel plasma and LCD TVs
Direct View TV
Changes the size of an image to fit the pixel size of a device without changing the shape
Scaler
Operates with beam of infrared light; components must be in line of sight with remote
Infrared Remote
Consisting of a separate projector (typically placed on a table or ceiling-mounted) and screen; Can display images up to 20 feet across, or larger
Front Projection
Ideal if there is little or no space for a TV or projector; Can be hung on the wall; Can be plasma or LCD
Flat Panel
What is the pre-installation video requirement for a CT3 cablecard?
A) An internal or external xfinity TV Tuner
Just launched by Comcast, these remotes talk to the STB via RF while using infrared to talk to the TV.
IR/RF Remote(XR2)
Large 24-pin connector in which audio is not provided
DVI
4-pin video only connector
S-Video
RCA wiring that uses Yellow Red and White connectors
Composite video
Improves picture quality; Makes routing and distribution easier; Allows images to be displayed in different ways
Signal Processor
Enables multiple video and audio signals to be selected and sent to one or more display devices
Switcher
What type of cable fulfills the video requirement for an internal or external xfinity TV user?
An A/B USB cable.
Operate components located throughout the household; Generates signals of given radio frequency
RF Remotes
Control all components; Can be programmed for individual components (uses 3 or 4 digit codes)
Universal Remotes
Perform operations on more than one component; can usually learn commands
Programmable Remotes
Control all components; Can be programmed for individual components (uses 3 or 4 digit codes)
Universal Remotes
Perform operations on more than one component; can usually learn commands
Programmable Remotes
Just launched by Comcast,these remotes talk to the STB via RF while using infrared to talk to the TV.
IR/RF Remote(XR2)
How far should seating be away from TV for Optimum viewing in a Home Theater setup?
Seating should be two times the diagonal wide-screen TV away from TV (example: seating should be 84” away from a 42” TV screen)
Name 4 of the 6 equipment requirements for an external digital cable tuner setup.
1) Windows Vista Home Premium or Ultimate Edition2) Vista digital cable compatible PC3) DVD-ROM Drive4) Audio Output Capabilities5) Internet Access6) Internal or External Xfinity TV Tuner with remote
What is the second step in the installation checklist?
Ensure eMTA is on customer’s account If you are not using a handheld or laptop, call dispatch to verify.
What is the third step in the installation checklist?
Greet the customer Introduce yourself and explain that service will be temporarily disconnected. Ensure that the customer is NOT using an existing service (for example, downloading a file, recording a TV program, etc.) prior to starting to work.
What is the fourth step in the installation checklist?
Determine if additional jacks or wiring is needed If additional telephone jacks need to be installed, have the customer indicate where he/she wants them installed, and get sign-off of any extra costs. If additional wiring is needed, consult customer on preferences, and follow local guidelines regarding wiring policies.
What is the fifth step in the installation checklist?
Confirm work order Note changes and obtain agreement before work
What is the sixth step in the installation checklist?
Determine if customer has an alarm system If yes, have customer put in ―test‖ or call the alarm company to test alarm.
What is the seventh step of the installation checklist?
If yes, see page 36 for Door Entry System Considerations.
What is the eighth step in the installation checklist?
Give customer Welcome Kit Customer can look over while you do work.
What is the ninth step in the installation checklist?
Test and verify customer equipment Make a call from all the outlets the customer wants changed over to verify they are functioning properly
Equation for calculating Exact Loss
Cable Loss + Passive Loss = Total Loss
Most trouble calls, including repeat trouble calls, in the CATV industry are found where?
Between the tap port and the customer’s television set.
The majority of troubles calls are due to what?
Poor connector installation or device attachments.
What types of problems can poorly installed F-Connectors cause the customer?
Tiling”One Moment Please” messageGhostingDistorted picture (hum)Intermittent service
The Top 5 Types of Connector Problems
- Moisture damage2. Long/short center conductor3. Connector not tightened to port4. Braid removed or too short/long5. Improper connector for cable type
Why is it improper to cut a center conductor a second time to (trim it) to fit a fitting?
A jagged center conductor can scratch the contacts inside the F-port creating reflections.
Name 3 of the 6 best practices for F- Connector Installation
- Use a prep tool with a stop2. Use the side of the compression tool to recheck dimensions3. With the correct prep tool, all the dimensions (1/4”) are setup correctly.4. Make sure the dielectric is flush with post face5. Make sure you hear an audible “click” when using the torque wrench to ensure the connector is tightened properly.6. Always compress fully
Name 5 of the 10 Best practices for Handling Coaxial Cable
- Do not use the wrong size clip2. Do not kink the cable3. Follow the cable’s bending radius4. Label each end of cable with a matching numbering system5. Do not allow a vehicle to run over the cable6. Always use a cable caddy when handling drop cable7. When pulling drop cable off a reel, do not pull loops out. Walk to the loop and unwnd it without kinking the cable.8. Never make 90-degree bends.9.Do not staple the cable10. Do not over tighten tie wraps, or stuff into house boxes.
What is the tenth step in the installation checklist?
Test and verify Comcast services Verify the Cable TV picture quality on all of the customer’s televisions. Be sure the cable modem has Block Sync and basic Web sites can be accessed prior to starting the installation.
What is the eleventh step in the installation checklist?
Determine location of eMTA Place near customer’s primary computer, if possible Keep eMTA away from wireless devices, access by children/pets Avoid attics and spaces that are not temperature controlled
What is the twelve step in the installation checklist?
Complete Onsite Quality Assurance Check Check for signal leakage. Check for inferior/substandard cable, connectors, andcraftsmanship. Check for any filters/traps that may have existed within aprevious installation and remove. If Xfinity Internet does exist, check that the modem isconnected to a ―home run‖ coaxial outlet. If Xfinity Internet does not exist, determine the route for a coaxial cable from a splitter near the ground block to the customer’s PC location. Test to verify that the coaxial portion of the home wiring is properly bonded. Determine the route for a ―home run‖ phone line from the customer’s PC location to the NID. For customers with alarms systems, a ―home run’ phone line to the NID is a required practice to ensure the alarm equipment can seize the customer’s phone line to call out during a potential emergency scenario.
Series-6 cable bending radius:
2.5”
Series-7 cable bending radius:
4”
What are the two ways to typically connect the eMTA to the customer’s inside wiring?
- Direct line from NID to eMTA using Scotchlok connectors2. Via a four-pair jumper
What is involved in the “Isolate” step of the troubleshooting process?
- Measure and record signal levels at outlets, splitter, ground block and tap2. Inspect all connectors, cable, and splitters and replace as needed3. Ensure all equipment is connected properly..4. Use Bypass Method to isolate bad equipment5. Perform Ingress Scan at both the ground block and the tap with all CPE connected.6. Use your Divide and Conquer techniques to cut the system in half to locate the fault
What frequency range is tested in a downstream Ingress resistance test?
88-108 MHz(FM Band) downstream
What is the web address for most Comcast modems and eMTAs
http://192.168.100.1
What frequency range is tested in an upstream spectrum test?
5-42 MHz
What is the acceptable measurement for both the upstream spectrum test and the Ingress resistance test?
-30 dBmV or lower
what are four benefits to an employer who uses teleworker?
Single contract, unified billing, online ordering and management, business class customer support
what are four benefits of teleworker for employees?
Multiple connections, comcast.net email, after hours use, Portal services
how any levels of teleworkers are there?
2
what are the names of of the two levels of teleworker?
Standard and enhanced
what is the major difference between the two teleworker service levels?
speed
how does a technician know the a teleworker customer from a CHSI customer?
the work order
what paper work does a technician give a teleworker at the end of the install?
None
RF:
RF or Radio Frequency refers to an electromagnetic wave that generally falls in the frequency range of 3 kHz to 300 GHz.
MHz (Megahertz):
Equal to one million Hz. Video signal bandwidth is typically expressed in megahertz
All FM radio stations transmit in a band of frequencies between:
88 and 108 MHz
Spectrum:
A range of wavelengths of electromagnetic emission
AM radio:
535 kHz to 1.7 MHz
Short wave radio:
5.9 to 26.1 MHz
Aircraft navigation frequencies:
110 to 137 MHz
Broadcast television stations: VHF low band channels 2 through 6
54 to 88 MHz
Broadcast television stations: VHF high band channels 7 through 13
174 to 220 MHz
The difference between transmitted and received power resulting from the loss through equipment, lines, or other transmission devices; usually expressed in decibels.
Attenuation
Coax attenuation specifications are based on:
100 feet of cable at 68 deg F
Each 10 degree increase in temperature results in a
1.2% increase in attenuation
The variable in calculating attenuation is always
The frequency
At 50 MHz, 100 feet of RG6 cable loses roughly
1.5 dBmV
At 400 MHz, 100 feet of RG6 cable loses roughly
4 dB
At 750 MHz, 100 feet of RG6 cable loses roughly
5.5 dB
The insulating material separating two conductors such as that between the center conductor and sheath in a coaxial cable
Dielectric
High frequencies travel in the very ____ of the center conductor
skin
Damage to the copper or silver skin of the center conductor will directly affect ____ _________ signals
high frequency
_____ ___________ utilize more of the cross-sectional area of the conductor and are more forgiving when it comes to imperfections in the copper plating
Lower frequencies
The property of higher frequencies travelling on the outer portion of a conductor is called the ____ ______
skin effect
A passive signal splitting device, with minimum signal loss between the input port and the output port (through loss), a specified coupling loss between the input port and the tap port (tap or coupler loss), and very high loss between the output port and tap port (isolation)
Directional coupler
A subunit of a larger unit called the bel:
decibel
Is a measure of the ability of a circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output
Gain
An increase of 3 dB _______ the signal power
doubles
Anytime an RF signal changes by 3 dB, the signal power is either _______ (+3 dB) or ___ __ ____ (-3 dB)
doubledcut in half
A signal of 0 dBmV corresponds to
1 mV across a 75-ohm impedance
(Attenuation x Footage)
Cable Loss
(Cable Loss + Passive Loss)
Total Loss
(Known Level – Total Loss)
Expected Level
A measure of the received carrier strength relative to the strength of the received noise
Carrier to Noise (C/N) ratio
A network architecture developed by the cable industry, which typically uses fiber optic cables to bring signals to selected areas of the system called nodes, which are usually based on the number of subscribers to be served
Hybrid Fiber Coax (HFC)
An advantage of fiber is:
It has bandwidth many times greater than coaxial cable and can travel great distances without amplification
The width of a band of frequencies
Bandwidth
Passage of an outside signal into the cable; can result in noise and disruption of the desired signal
Ingress
A standard for home entertainment networking in which existing subscriber drop coaxial cabling and components are used to interconnect set-top boxes
MoCA
Allows up to 16 devices on the network, with a maximum of 300 feet of cable
MoCA 1.1
MoCA 1.1 offers ___ ____ MAC rates and __ node network extensions
175 Mbps16
MoCA 1.1 operates in the ___ – ____ MHz frequencyrange
500 – 1500
MoCA 2.0: offers net throughput MAC rates of ________(baseline mode) and _______ (enhanced mode)
400 Mbps800 Mbps
MoCA 2.0 operates in the ___ - ____ MHz frequency range
500 - 1650
To ensure that MoCA energy remains within the home, the CommTech 3 must install a __________ in the drop
POE filter
FCC part 76.614
States that any leakage source which produces a field strength of 20 uV/m or greater at a distance of 3 meters in the aeronautical radio frequency bands shall be noted and such leakage sources shall be repaired within a reasonable period of time
Three main features of OWE:
First Time User Experience (FTUE) XFINITY ProfileProgress Bar
The residential services are:
XFINITY TVXFINITY VoiceXFINITY InternetXFINITY Home
Xfinity apps
XFINITY Connect AppXFINITY Home AppXFINITY TV Go AppXFINITY Player AppXFINITY Remote AppXFINITY Wi-Fi App
Suite of applications that enable customers to enjoy the services they have from Comcast on as many platforms as possible
Converged Products:
Allows customers to make outgoing calls via a virtual telephone number using a mobile device without using wireless minutes
Voice 2go
The three main components of a Home Theater system are:
AudioVideoEnvironment
There are three significant considerations in a Home Theater application
Audio qualityAudio formatsAudio equipment
Latent or out-of-sync audio
Lip-Sync
The different types of audio formats are:
MonoStereoSurround Sound
Key elements of a surround sound system are:
PreamplifierPower AmplifierSurround Sound ProcessorAudio/Video Receiver
Tiny dots that convey light and combine to form a video picture
Pixel
Short for “picture element.”
Pixel
The number of scans from the left side of the display to the right and back that occur in one second
Horizontal Scan Rate
The number of times per second that the scan sequence is repeated from the top of the display
Vertical Scan Rate
Visible fading of luminance between scan cycles on video displays
Flicker
The method of displaying television pictures in which the picture is displayed in two halves (one of odd-numbered lines, one of even-numbered lines), that are interlaced together to create the full picture
Interlaced scanning
Standard television pictures are composed of ___ horizontal lines that scan across the screen in less than the blink of an eye
480
The ____ format utilizes two sequential fields of 540 lines each
1080i
Interlacing produces __ fields or __ complete frames every second
6030
Television pictures are displayed in a single pass, instead of the two fields used with interlaced scanning
progressive scanning
The common progressive scan standards that you will see are:
480p, 720p, and 1080p
Identifies and removes redundant information between successive frames of the picture
MPEG compression
Separating successive frames into two types of video information—that which remains unchanged from frame to frame, and that which is updated frame to frame
Digital Compression
The most important part of a Home Theater system is the?
video display
The three main steps involved in site preparation when installing new equipment in a customers home are:
Determining customer expectationsAnalyzing the current setupPlanning the signal flow
A common problem with Home Theater systems is:
no picture or poor picture
The most common causes of picture failure in a Home Theater system are:
Wrong display settings.Lack of power to various components.Cable routing malfunction, loose or disconnected cables
Ground loop issues are basically caused by
A 60-cycle AC component in the audio connections
When multiple carriers oscillating at different frequencies are transported simultaneously in the same medium
Frequency Division Multiplexing (FDM)
A return path impairment that can have a severe effect on return path signal quality
CPD
The transfer of energy from one device to another is most successful when both devices are of the same
Impedance
Signals propagate through either of two mediums
guided and unguided
Provides a physical path along which the signals are transported; such as those used in cable TV
Guided media
Can be water or the air around us. The signal is transmitted from a transmit antenna to a receive antenna
Unguided media
Three components of an electrical circuit:
VoltageCurrentResistance
The electromotive force (or pressure) that causes electrons to flow in a circuit
Voltage (E)
The amount of pressure required to cause one ampere of current to flow through one ohm of resistance
One volt
The flow of electrons through a conductor
Current (I)
The opposition a material offers to the flow of electrical current
Resistance (R)
One coulomb passing a given point in one second is equivalent to
One amp
German physicist, investigated galvanic currents and established the mathematical relationship between voltage, current, and resistance
Georg Simon Ohm
voltage =
current X resistance
A flow of IP data supplied to a processor at a rate fast enough forreal-time decoding
Streaming
Enables media files—movies, TV shows, music, and so on—to be played on TV, from various sources like computers, hard drives, the Internet, and media servers
Home Media Streaming
An all-in-one device that connects the customer’s Internet, phone, and home networking, enabling them to share files with computers and other electronic products that are connected to their home network
Wireless Gateway
A term used in IP telephony for methodologies and transmission techniques that manage the delivery of voice, using IP packets
Voice over Internet Protocol (VoIP)
Three ways a customer can access Enhanced Voicemail:
- Dial *992. Dial home telephone number3. Online, through XFINITY Connect
A customer can access Enhanced Voicemail while away from home bypressing
, once the greeting begins
Customers can easily check their email, listen to voicemail, and manage their address book and calendar from any computer with an internet connection.
XFINITY Connect
XFINITY Connect allows customers to:
Review call historyEasily manage everything related to their account without calling Customer Service
How customers can access XFINITY Connect:
If a customer has XFINITY Internet and XFINITY Voice, the login is their primary email username and password.If a customer is only subscribing to XFINITY Voice, the login will be the XFINITY Voice 10-digit home telephone number and voicemail password.For a new voicemail setup, simply dial *99, the system will prompt you to create a new passcode. Note, the last four digits of the telephone number is NO LONGER the default passcode.
website to access Xfinity Connect
https://login.comcast.net/login
Phone service that transmits telephone calls over a public network, such as the Internet
IP Telephony
A term used in IP telephony for methodologies and transmission techniques that manage the delivery of voice, using IP packets
VoIP
Technology used to transmit voice and related calls over a data network
IP Phone/IP Voice
A device that allows the telephone company to route and connect customers to one another
Telephone Switch
Worldwide network of public circuit-switches used by traditional, local, and long-distance companies
Public Switched Telephone Network (PSTN)
Central Office (CO) server that routes calls to other IP-based phones or through the PSTN
Soft switch (Software Switch, VoIP Switch, or CMS)
A telephone line dedicated to a specific subscriber. This line sends signals through the system, based on a subscriber making and receiving calls.
Subscriber Line
A site where telecommunications companies (such as cellular and long-distance providers) physically interconnect their systems with other networks (such as local telephone companies or cable companies)
Point of Presence (POP)
A condition caused when packets are not received in the correct order, or when they take too long to arrive at their destination.
Jitter
Delay associated with inconsistencies, or impairments, in the data transport stream.
Latency
Voice packets are given priority over other types of data traveling within the Comcast network. This managed delivery ensures high-quality voice packet interpretation.
Dynamic Quality of Service (DQoS)
The only time a call from an XFINITY Voice customer may use the public Internet is when the receiving party is using an ______________________.
internet-based service
When a telephone is on-hook, there is a potential difference of 48 volts between the tip and ring. This is called?
Supervisory or idle voltage
Ring voltage:
It may be anywhere from 60–90 Volts Alternating Current (VAC) at a frequency of 20 Hz.
In North America, a ____ pattern is the standard ring cycle.
2-4, two seconds of ring voltage followed by a four-second pause
In legacy telephone networks, talk battery and ring voltage come from the?
Central Office
Always disconnect the inside wire (IW) from the_________ before working on the wiring.
NID or eMTA
The total REN value in an individual circuit should not be greater than?
5
CPE that may have REN specifications:
Answering machineFax machinePhone modemMonitoring devicesAlarm systems
The voice portion of the eMTA can interpret both
DTMF and pulse signaling
Also known as Touch-Tone, this form of audio signaling was introduced by Western Electric in 1963
DTMF: Dual-tone multi-frequency signaling
In earlier pulse dialing systems, noise generated in the copper pairs could be interpreted as a pulse by the switch rendering:
Wrong telephone numbers
An eMTA features up to ____ hours talk time and up to _____ hours of standby battery
fiveseven
An eMTA features up to ____ hours talk time and up to _____ hours of standby battery
fiveseven
When utilizing an in-house amplifier, the eMTA must be connected to a:
passive port
If the customer has opted for a backup battery, it is recommended that they also have a ___________ on hand, in the event of a power outage.
wired phone
eMTA Location Guidelines
Place near customer¡¦s primary computer, if possible.Do not place eMTA in an attic or unheated basement space.Do not place the eMTA too close to a furnace or in any other area that is environmentally unsuitable for the unit.Keep away from wireless devices, and access by children or pets.Ensure adequate ventilation
Do not place an in-home amplifier between the tap and the eMTA unless the amplifier has an approved:
eMTA port
eMTA battery provides _____________ hours of standby time in case of power outage
five to seven
Backup batteries will not be available for purchase from Comcast by customers subscribing to:
“Unlimited Select.”
All of a sudden, the eMTA Link lamp or LED goes off. What could be the reason?
Ethernet cable disconnected, or computer has been powereddown. Possibly the router has lost power
What does the eMTA Telephone light do when the telephone is off the hook?
The lamp flashes
What does the eMTA Telephone light do when the telephone is off the hook?
The lamp flashes
How do you know if the eMTA battery is low?
Indicates a low battery
If all the lights flash, it is an indication that:
foreign voltage is present.
Name two ways to discourage the customer from unplugging the eMTA from a dual jack when they are trying to unplug their phone.
Wire in such a manner that the eMTA is plugged into the bottom jack to minimize accidental disconnectionUse a red “Do not remove” tag to block the unused port
Once the eMTA is hooked up, you can access a GUI to check signal levels by using:
192.168.100.1
Line test set common features:
» Monitor mode (on hook): Primarily for monitoring of a telephone line while on hook.» Talk mode (off hook): Will draw dial tone and is used to test the analog phone line» Speaker phone: Provides hands-free listening in both monitor and talk modes» Polarity test: Used to check polarity of the tip and ring, for tone signaling, and receiving signal from the tone-generating unit» Talk battery: The butt set can power a wire pair for voice communications» Dialing and calling capability
Indicates the pair polarity, detects a short circuit, and indicates the presence of “talk battery” (connection to the network)
Toner
Older wiring is often referred to as ____________, or Category 1 (CAT 1) wire.
station wire
With station wire the_____ and___ wires are used for the primary line.
greenred
The twists in Category 3,5 and 6 wire help prevent __________ and cancel out noise that might be induced onto the wire from adjacent pairs or exposed wire.
cross talk
All the wires used at Comcast start with “white” because white (tip) refers to the first five pairs:
» White/Blue» White/Orange» White/Green» White/Brown» White/Slate
____________________ silver satin cables should always be used from the eMTA to the wall jack, to prevent reverse polarity.
Electrically straight
4P4C connector -
4 wire (handset coil cord)
6P2C connector -
2 wire – RJ11 – one phone
6P4C connector -
4 wire – RJ14 – two phones
6P6C connector -
6 wire - RJ25 – three phones
8P8C connector -
8 wire – RJ45 - Ethernet
Contrary to popular belief, the handset cord is not a ______________ It has been erroneously referred to as an RJ22, RJ10, or RJ9. It is simply a unique sized 4P4C connector designed for the handset.
registered jack
When a fax machine is used with XFINITY Voice, the fax machine will:
Share the incoming phone line
Pre-installation Guidelines
Verify that tools and equipment have been chargedStock XFINITY Voice Welcome KitsEnsure that pocket guides/other resources are availableKnow how to use the mobile device/laptop and the IVRUnderstand troubleshooting stepsCheck work order; find out whether the customer requires a DOCSIS 3.0 deviceVerify that XFINITY Voice is shown on the work order before attempting the installation
What to do before beginning the actual installation
Confirm that the job is indeed what the customer orderedDetermine if additional jacks or wiring is neededHand the customer a Welcome KitDetermine if the customer has a monitored alarm systemAsk if the telephone is connected to an entry buzzer or door-entry systemAsk the customer what devices they have at home that are connected to the telephone line. This will help in ensuring compatibility.If there is a monitored security alarm, have the customer notify the alarm service to test the functionality of the alarm system.Once tested and verified, or if alarm is not monitored, ask the customer to place the alarm in “test” mode.
In a ____________ wiring configuration, the twisted-pair coming in from the NID goes, consecutively, through all the phone jacks
loop-through
In homes with loop-through wiring, the primary line may have been moved to the ____________ pair because of damage to the _________ pair somewhere in the wall
black/yellow red/green
Disadvantage of loop-through wiring configurations
If one part of the loop goes bad, the rest of the circuit is often affected.It inhibits/complicates addition of a special service, such as a fax machine, to just one phone jack.
In a home-run wiring configuration, also known as ____, each outlet is fed directly from a central location
star
When to use back-feed installation:
After determining that the existing wire can support a back-feed, and that it is the most reliable and efficient solution
When to use dedicated feed:
Whenever the customer has a PBX and/or monitored alarm system or when the existing phone jack wiring is determined to be faulty
Disadvantage of dedicated feed installation:
Requires spare pairs that are not always availableMay require installation of an additional telephone wire to facilitate the feed
Only _________ alarm systems should be connected to the phone service
monitored
Allows an alarm panel to control access to active phone pairs, and seize those pairs even if the customer is using the telephone
Line seizure
Be sure that the alarm system is in ________ before beginning work, to ensure that an alarm is not triggered
Test Mode
Some ILECs utilize “______________,” a service that keeps talk battery on the pairs even if the location no longer subscribes to their phone service
soft dial tone
Before the eMTA can be connected to the customer’s home wiring, the existing service must be disconnected at the?
NID
Unplugging the modular connector in the NID is a safety step. It prevents?
being hit by ring voltage
Insulate wiring disconnected at the NID with __________or similar if it is going to have continuity back to the eMTA.
Scotchloks
What is the preferred method of connecting the eMTA to the house wiring?
Disconnect the ILEC and connect the eMTA with a dedicated line to the NID
An _____ jack isolates the alarm panel from the eMTA in the telephone circuit.
RJ31X
In a phone installation with an alarm system, a _________ _____ _____ is always the first active device in the telephone circuit
monitored alarm panel
Exceptions to opening the alarm panel:
When you do not know the color/pair of inside wiring that has been previously used to supply dial tone from the NID to the RJ31XWhen you need to isolate a trouble condition
Rule of Three for XFINITY Voice:
- Confirm the customer’s new telephone number.2. Illustrate how to use voicemail, referencing the steps in the Welcome Kit.3. Talk about XFINITY Connect where customers can go online to check voicemail, see call history, or set options
There are three methods for activating XFINITY Voice services. They are (in order of preference):
- Via the workforce management application on the company-issued mobile device or laptop2. Via the Online Tech Activation Tool, using the customer’s computer3. Via the Interactive Voice Response (IVR).
Often called Cable Modem MAC, is typically used when provisioning an installation for both XFINITY Voice and Internet
CMAC
Refers to the telephone only portion of the eMTA. It is typically used for provisioning XFINITY Voice when using the IVR
MTA-MAC
MAC address added to the customer’s account in CSG/ACSR markets
CMAC
Typically used for provisioning XFINITY Voice when using the IVR.
MTA-MAC
Used for provisioning via the mobile device in AMDOCS/Comtrac/Cable Data markets
The serial number
An eMTA or modem that has not been activated receives a ____________boot file which allows it to communicate with our network but not surf the Internet
walledgarden
After activation the first test call:
verifies inbound calling, long distance, and calling features
After activation and placing the first test call, keep the first test call connected and prompt a second test call to validate:
call waiting and voicemail
If a password is required, to validate voice mail, use?
the last four digits of the telephone number
Use only________________to connect the fax machine
single pair silver satin (two wires)
Single pair silver satin utilizes pins ______ of the connector
2 and 3
Why do we only use single pair silver satin wire for fax machines?
Using two-pair (four wire) silver satin may allow voltage to be present on pins 1 and 4 of the modular connector. The eMTA provides supervisory voltage on pair two even if the customer subscribes to only one phone line. This pair two voltage wreaks havoc with several models of fax.
There are three categories that can help us determine where an XFINITY Voice problem may occur
RF or coaxCopper wiring or jacksThe eMTA
Keenness and depth of perception, discernment, or discrimination especially in practical matters
Acumen
The ability to make good judgments and quick decisions, typically in a particular domain
Business acumen
The Comcast Credo
“We will deliver a superior experience to our customers every day. Our products will be the best and we will offer the most customer-friendly and reliable service in the market.”
Two versions of Business TV:
Private ViewPublic View
Typically private/professional businesses where food and/or alcohol is not sold for immediate consumption/not the main source of revenue.
Private View
Includes, but is not limited to, locations where the bulk of the revenue is derived from the sale of food and/or alcohol
Public View
Some services available to Residential customers are excluded in Business Services. The excluded services are:
DVRVODImpulse PPV (IPPV)Premium channels
Business TV is not available to venues that:
Charge an admission or entry fee. (However, a monthly or yearly membership is not considered as admission fee. Thus, Business TV is made available to health clubs or special interest clubs.)
Service levels for Business TV Private View:
Business TV BasicBusiness TV Information & EntertainmentBusiness TV StandardBusiness TV Preferred
Business customers are required to sign a ______________________ in order to establish service.
service order agreement/contract
Service levels for Business TV Public View:
BasicDigital Basic PlusDigital StandardDigital DeluxeSports & Entertainment StandardSports & Entertainment Deluxe
There are three major music licensing organizations which provide the rights for businesses to play licensed recordings:
ASCAPBMISESAC
Benefits of bundling
FlexibleOne service providerEfficientCost effectivePeace of mind
Most VoIP service providers use the _____________(Internet Phone) to carry phone traffic; Comcast does not.
public Internet
Business Voice is transported over _____________________________, giving customers the clarity they expect.
Comcast’s private, advanced broadband network
Business Voice Service Capabilities & Customer Support
Operator AssistanceDirectory AssistanceCall RestrictionsE911 Emergency CallsDo-Not-Call RegistryDirectory Listings
Features that are available only to Business customers:
Call Forward No AnswerHunt GroupsExtension Dialing
A serviceability check consist of two components:
- Serviceability of the location2. E911 serviceability
The demarcation point for Small Business Voice services is?
The RJ telephone connector on the back of the eMTA
When installing Business Voice, always use a?
dedicated eMTAThe Ethernet port should not be used for Internet service
___________ circuits can be noisy and more susceptible to migration and corrosion
Ground start
_________circuits are almost always used in IP voice telephony
Loop start
1 Baud equals ____, thus 9600 Baud is _______.
1 bps9.6kbps
Metro Ethernet (Metro-e) customers can select one of the three Classes of Service (CoS) that best meets their applications’ performance requirements:
- Basic2. Priority3. Premium
What is the speed range for Metro-e?
1Mbps–10Gbps
What website would you direct a customer to for anything business class related?
http://business.comcast.com/
Business Internet Customer Support a technician can be dispatched within ______, including on weekends and holidays
4 hours
Combines the functions of a cable modem and a router in a single device
IP gateway
It is the process of modifying IP address information in IPv4 headers
NAT
Some routers come with a ___________option which, when enabled, essentially disables the networking functionality and the gateway basically becomes a modem.
Bridge Mode
Managed Internet access, available to corporations that have a distributed, mobile workforce of at least 100 persons
Teleworker Internet
DOCSIS 1.0 issued
March 1997
DOCSIS 1.1 added full standardization and quality of service capabilities
April 1999
DOCSIS 2.0 released, to meet the demand for enhanced upstream transmission speeds
December 2001
DOCSIS 3.0 released; it supported enhanced upstream and downstream transmission speeds and Internet Protocol version 6 (IPv6).
August 2006
Aims to support capacities of at least 10Gbit/s downstream and 1Gbit/s upstream
DOCSIS 3.1
All DOCISIS specifications currently support:
6 MHz wide downstream channels, modulated at 64 QAM or 256 QAM, with receive levels between -15 and +15 dBmv at the cable modem
Upstream channels are __ MHz wide and depending on the DOCSIS version, support these upstream modulation schemes:
3 MHzQPSK, 16 QAM, 32 QAM, and 64 QAM
Transmit levels for QPSK are:
+8 to +58 dBmv
Transmit levels for 64 QAM are:
+8 to +55 dBmv
Comcast has allocated downstream DOCSIS carriers to be located in the higher end of the downstream bandwidth, somewhere between:
500 and 700 MHz
DOCSIS supports frequencies anywhere between:
88 MHz and 860 MHz
Upstream carriers are currently located somewhere between:
5 and 42 MHz
Technology that allows multiple cable boxes to utilize a single radio channel. Each box is assigned a code for its upstream bit stream
S-CDMA: Synchronous - Code Division Multiple Access
Load-sharing technique for logically combiningmultiple DOCSIS channels
Channel Bonding
Electromagnetic wave that generally falls in the frequency range of 3 kHz to 300 GHz
RF or Radio Frequency
A protocol for assigning dynamic IP addresses to devices on a network
Dynamic Host Configuration Protocol (DHCP)
The modem scans the downstream QAM channels, looking for an upstream channel descriptor. A __ occurs if the cable modem does not find one within a few seconds
T1
The modem waits for an opportunity to communicate with the CMTS. If it does not get an opportunity within about 12 seconds, a __ timeout occurs.
T2
The cable modem has sent a ranging request upstream to the CMTS for transmit and timing information. If the modem does not get a response within 200 milliseconds, a __ Timeout occurs. After 16 attempts, the modem will reboot to restart the registration process from the beginning.
T3
Once a cable modem is online, it continues to communicate with the CMTS. The modem watches for Keep Alive requests from the CMTS. If it does not receive one after 30 seconds, a __ timeout occurs.
T4
After __ T4s, the cable modem will reset
16
T3 and T4 timeouts can be a sign of an
upstream or downstream problem
A complex number with a resistive and reactive component. It is a function of the frequency of the applied signal, and is unrelated to length
Characteristic Impedance
The condition that results when two components of a system are operating at a different impedance
Impedance Mismatch
Performs a function similar to that of a cable amplifier’s equalizer. However, instead of equalizing the entire 50-860 MHz downstream or 5-42 MHz upstream, it deals with just a single channel.
Adaptive Equalization Technology
A feature in Scout that shows the presence or absence of linear distortions in the RF portion of the return path
Scout Flux
Cable modems communicate with the CMTS every _________ to characterize network conditions
20 seconds
How do you access Scout Flux data for a single modem
Go to the Device Watch tab and select Customer ReportIn the search box, you can enter an account number, phone number, MAC address, IP address, FQDN, or name for the customer.After entering the information, click the Submit buttonThe customer report will look slightly different for various customers, due to the equipment on the accountClick on the CM1 page (if it shows up on your screen), and go to the Modem Toolbox at the bottom of the pageTo open up Scout Flux, click on the Scout Flux icon - the sine wave
To troubleshoot single premise issues in Scout Flux, you will need to concentrate on the ____________________________ graphs shown in the second row
In-Channel Frequency Response (ICFR)
A measurement of how consistent the signal response is from the beginning to the end of the channel space
ICFR
ICFR values, and what they indicate:> 3.0 dB -
-the problem should be investigated and fixed-required level to pass Techlink certification-ideal circumstances at the modem
ICFR Ripple Count:Fewer ripples would generally indicate a?whereas numerous ripples would most llikely indicate a?
house problemplant problem
The adaptive equalizers are sent fresh commands for equalization every?
20 seconds