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1>Following different types of customers have access to broadband networks a: corporate or enterprise users who have campuswide networks

b: service providers

c: residential and small business customers who have multimedia requirements Ans: __________ (a/b/c/all)

2>MSO stands for__________

3>HFC stands for__________

4>Following types of access technology are currently available to residential and small business customers a: HFC/cable modem

b: DSL

Ans: __________ (a/b/both)

5>In the case of __________network, information is transmitted to the cable modem at the customer site from an MSO facility (DSL/HFC)

6>The access network based on_______ uses the existing twisted pair loop facility from a central office to the customer premises (DSL/HFC)

7>Different modes of access rely on following technologies a: HFC cable

b: DSL

c: wireless communication d: satellite communication Ans: ___________ (a/b/c/d/all)

8>Broadband access technologies currently consist of following mutually independent methods a: HFC cable

b: DSL

c: wireless communication d: satellite communication Ans: ___________ (a/b/c/d/all)

9>___________uses television transmission facilities and cable modems, and is the most widely deployed means of access of the four (HFC/DSL/wireless/satellite)

10>In _____way telephony return configuration, the downstream signal to the customer traverses cable (one/two)______

11>In____ way HFC mode, both upstream and downstream are handled by the HFC medium using a cable modem (one/two)_______

12>DSL technology has 3 different implementations and is generally referred to as xDSL , where the x represents asymmetric (A), high speed (H) Or very high speed (V) transmission (true/false)_______

13>Following broad categories of service are being offered in wireless access technology a: MMDS/WCS

b: LMDS c: ISM

Ans: ___________ (a/b/c/all)

14>MMDS/WCS stands for___________

15>LMDS stands for___________

16>ISM stands for__________

17>___________operates over the 2500-2686 MHz band and includes both one-way wireless with telephony return and two-way wireless implementations, it has a range of up to 35 miles (MMDS/WCS or LMDS or ISM)

18>___________operates over two frequency bands, it has a range of about 3miles (MMDS/WCS or LMDS or ISM)

19>___________operates over two frequency bands , the lower band has a range of only 0.5 mile but the higher band has a range of up to 15 miles (MMDS/WCS or LMDS or ISM)

20>___________technology is based on existing cable television technology (DSL/HFC) 21>The signal going from the head end to the customer premises is called ___________signal (downstream/forward path/either)

22>The signal going from the customer premises to the head end is called___________ signal (upstream/reverse path/either)

23>NIU stands for___________

24>NID stands for___________

25>At the customer premises, ___________is the demarcation point between the customer network and service provider network (NIU/NID/either)

26>The _________modem converts analog signal to Ethernet output (cable/telephone) 27>Match the following

Telephone modem ,28.8 kbps : approximately 1 second ISDN ,4 kbps : 6-8 minutes

cable mode, 10 Mbps : 1-1.5 minutes

28>The HFC broadband system with ___can process data much faster than can a conventional____or____

(ISDN/telephone modem/cable modem) 29>HFC technology is based on a: broadband LAN

b: asymmetric bandwidth allocation to achieve two way communication

c: radio frequency spread spectrum technique for carrying multiple signals over the HFC

d: radio frequency spectrum allocation to carry multimedia telephony , television and computer communication services

Ans: ___________ (a/b/c/d/all)

30>In Broadband LAN architecture, the downstream signals are in the _____MHz band and the upstream signals are in the______ MHz band (5-42/50/860)

31>In Broadband LAN architecture, the downstream bandwidth of a channel is ____MHz and the upstream bandwidth varies from___ kHz to ____MHz (3.2/6/200)

32>___________modem modulates and demodulates the digital signal from the customer equipment to the radio frequency signal carried on the cable (telephone/cable/either)

33>Following different modulation techniques support different capabilities in cable modem a: ASK

b: FSK c: PSL

Ans: ___________ (a/b/c/all)

34>In cable modem, the most commonly used modulation technique are___________ (QPSK/QAM/both) 35>_____is the number of bits per second traversing the medium .______is the number of signal units per second (baud rate/bit rate)

36>_____equals ______times the number of bits per symbol (bit rate/baud rate)

37>In____ modulation, the four levels are represented by the four states 0, 90, 270 and 180 (QAM/QPSK)_______

38>Phase shift keying is limited by the difficulty of detecting small phase shifts (true/false)___________

39>___________is the preferred method of modulation for the downstream signal in the cable modem (QPSK/QAM)

40>Match the following Toshiba : 40Mbps RCA DCM105 : 38Mbps Cisco : 10Mbps LANcity : 5.36 Msym/sec Motorola:

41>Cable modems with a downstream speed of___ Mbps and an upstream speed of ____Mbps are commonly available now (10/30/40)____

42>______uses pseudotree topology (DSL/HFC) 43>MCNS stands for___________

44>DAVIS stands for___________

45>DOCSIS stands for___________

46>___________standard being developed by the MCNS is the industry standard for cable modem system specification (DOCSIS/DAVIS)

47>Some cable modems are designed as one way, and the return path is via telephone link called___________

(telco return/telecom return) 48>CMTS stands for___________

49>All cable modems terminate at a server called ___________at the head end (LMDS/CMTS)

50>___________consists of multiple pairs of optical fibers connecting fiber nodes (DSL plant/HFC plant) 51>In an HFC network, the coaxial cable that connects to the NIU in the home is referred to as___________ in CATV terminology (tap to cable/tap to TV)

52>The spectrum use in HFC extends only to____ MHz (750/860)_______

53>In Cable modem, the upstream signal is allocated the low end of the spectrum from___ to ___ MHz. The downstream signal is allocated from___ to ___MHz (5/42/54/750)

54>Using noisy conditions, the cable modem could dynamically switch to different downstream and upstream channels to improve the quality of service. Such a feature is called_____ (phase agile capability/frequency agile capability)

55>CMCI stands for___________

56>DOCS-OSSI stands for___________

57>CMTRI stands for___________

58>DOCSS stands for___________

59>RFI stands for___________

60>In data over cable system reference architecture, the head end is connected to WAN, and multiple head ends can be connected via the WAN to a regional center head end. In such a case, the local head end is referred to

as___________ hub (centralized/distribution)

61>DOCSIS places interfaces into following categories a: data interface

b: operations support system interfaces and telephony return interface c: RF and security interfaces

Ans: ___________ (a/b/c/all) 62>Match the following

data interface : RFI ,DOCSS

operations support system interfaces & telephony return interface : CMTRI ,DOCS-OSPG RF & security interface : CMCI, CMT -NSI CMTS 63>Management of an HFC system with cable modems is more complex than the management of ___________network (computer/telecommunication/either)

64>Management of ____network is involved with data layers. Management of _______network is involved with physical layer (computer/telecommunication)

65>HFC management encompasses ___________management (data layer/physical layer/both) 66>Following functional area are identified in the management of BIDS

a: network maintenance b: subscriber support c: planning

Ans: ___________ (a/b/c/all) 67>BIDS stands for___________

68>At the physical layer, HFC access network management functions include a: detection of errors and corrections of ingress noise interference

b: amplifier gains

c: signal levels at the cable modems d: power supply voltages

Ans: ______ (a/b/c/d/all)

69>At the data link layer, HFC access network management functions include a: traditional configuration management

b: fault management

c: performance management Ans: ___________ (a/b/c/all)

70>Cable modem and CMTS can be managed with ___________management (SMTP/SNMP) 71>CMTS is also called___________ (trail end reference/head end reference)

72>DOCS stands for ___________

73>The HFC element management can be divided into following components a: cable modem management

b: CMTS management c: HFC link management d: RF spectrum management Ans: ___________ (a/b/c/d/all)

74>The DOCS interface objects group, docsIfMIBObjects, has following subgroups a: base interface objects group

b: CM interface objects group c: CMTS interface objects group Ans: ___________ (a/b/c/all)

75>The baseline privacy objects group, docsBpiMIBObjects, has ____subgroups (7/8/9)_______

76>Match the following

docsBpiCmObjects : baseline privacy CMTS multicast control group docsBpiCmBaseTable : baseline privacy CMTS authorization table docsBpiCmTEKTable : baseline privacy CMTS objects

docsBpiCmtsObjects : baseline privacy CM base and authorization table docsBpiCmtsBaseTable : baseline privacy objects for CM

docsBpiCmtsAuthTable : baseline privacy traffic encryption key table docsBpiCmtsTEKTable : baseline privacy CMTS base table

docsBpiMulticastcontrol : baseline privacy CMTS traffic encryption key table 77>Match the following

docsQosMIBObjects : mapping of flows to service classes

docsQosIpPktClass-Table : set of DOCSIS Qos flows active in the device docsQosEthPktClass-Table : contains QOS table

docsQosServiceClassGroup : IP packet classification table containing class information on direction, type, flow, source and destination

docsQosServiceClassTable : DOCSIS QOS extensions of MIB objects

docsQosFlowTable : ethernet packet classification containing information similar to the IP packet docsQosSidToClass-Table : set of DOCSIS QOS service classes defined in the managed object

docsQosFlowToClassTable : mapping of service classes to SIDs 78>Match the following

docsDevMIBObjects : CPE IP management and anti-spoofing group on cable modems docsDevBase : provides control and logging for event reporting

docsDevNmAccessTable : provides information for network downloadable software upgrades docsDevSoftware : extends MIB2 system group with objects needed for cable device system management

docsDevServer : Objects of the cable modem and CMTS device docsDevEvnt : defines the minimum level of SNMP access security

docsDevFilter : provides information about the progress of the interaction with various provisioning servers

docsDevCpe : configures filter at link layer and IP layer for bridged data traffic 79>SMS stands for___________

80>____________deals with the management of RF spectrum allocations to different digital services both in the downstream and upstream bands (MMS/SMS)

81>the main motivating factor for employing _____for access technology in multimedia service is the preexistence of local loop facilities to most residences (HFC/DSL)______

82>HDSL stands for___________

83>ADSL stands for___________

84>VDSL stands for___________

85>___________operates at a T1 or E1 data rate in a duplex mode with two pairs of wires (ADSL/HDSL/VDSL) 86>SDSL stands for___________

87>The duplex mode is defined as___ way communication with the same speed in both direction (one/two)________

88>___________is the same as the HDSL, except the two way duplex communication occurs ove a single twisted pair (ADSL/SDSL/VDSL)

89>_____&______both operate asymmetrically (ADSL/SDSL/VDSL/HDSL) 90>_____signal has a larger bandwidth than ______signal (downstream/upstream)

91>The difference between ADSL and VDSL is that _______operates at higher data rates over shorter lines than____ (VDSL/ADSL)

92>ATU stands for___________

93>ATU is also baked the________ modem (HDSL/ADSL) 94>POTS stands for___________

95>Development is in progress to eliminate the splitter at the customer site. This configuration is referred to as___________ (ADSL lite/HDSL lite)

96>Following are the schemes for separating the upstream and downstream frequency bands: ___________

(FDM/echo cancellation/both)

97>In___________, after the upstream and downstream bands have been separated, each band is divided into one or more high speed channels and one or more low speed channels (FDM/echo cancellation)

98>DSLAM stands for___________

99>ONU stands for___________

100>CEBus Stands for___________

101>PDN stands for__________

102>SOHO stands for__________

103>PSTN stands for__________

104>Real time signals such as audio and real time video, use a fast buffering scheme and hence are referred to as__________ (fast channel/interleaved channel)

105>Digital data that can tolerate delay make use of slow buffers and are interleaved between fast signals. The digital data channel is referred to as__________ (fast channel/interleaved channel)

106>ADSL management is __________the line encoding scheme used (dependent on/independent of) 107>CAP stands for __________

108>DMT stands for__________

109>The echoing phenomenon occurs in telephone systems because of crosstalk between neighboring pairs of wires in a bundle (true/false)__________

110>Two signals transmitted from a central office can couple with each other, which is referred to as__________

crosstalk (near end/far end)

111>Two signals traversing in opposite directions can interfere with each other, which is referred to as__________

crosstalk (near end/far end)

112>Near end and far end crosstalk can be mitigated by using __________technique (FDM/echo cancellation) 113>In__________, the entire loop bandwidth is used in the encoding (DMT/CAP)

114>in__________, the entire bandwidth of approximately 1.1 MHz Is split into 256 subchannels, each of an approximately 4 kHz band (DMT/CAP)

115>In DMT, the number of downstream subchannels is either____ if echo cancellation is used or ______if echo cancellation is not used (218/250)_

116>Management of the ADSL network involves following network elements

a: management communications protocol across the network management subinterface of the V interface b: management communications protocol across the U interfaces between ATU-C and ATU-R

c: parameters and operations with the ATU-C d: parameters and operations within the ATU-R e: ATU-R side of the T interface

Ans: __________ (a/b/c/d/e/all)

117>In ADSL network management elements, the management function at the physical layer involves following entities

a: physical channel b: fast channel c: interleaved channel Ans: __________ (a/b/c/all) 118>Match the following

ADSL line type : time interval to downshift ADSL line coding : time interval to upshift

Target noise margin : mode1- manual, mode2- select at start up, mode3- dynamic Maximum noise margin : modem reduces power above this threshold

Minimum noise margin : ADSL coding type

Rate adaptation mode : five types-no channel, fast, interleaved, either or both Upshift noise margin : noise margin under steady state

Minimum time interval for upshift rate adaptation : modem increase power below this margin Downshift noise margin : threshold for modem increases data rate Minimum time interval for downshift rate adaptation : threshold for modem decrease data rate 119>Match the following

Desired maximum rate : vendor specific serial number Desired minimum rate : vendor specific version Rate adaptation ratio : vendor ID assigned by T1E1.4 Maximum interleave delay : Rate down change alarm Alarm thresholds : rate up change alarm

Rate up threshold : 15min count threshold on loss of signal, frame, poser, and error seconds Rate down threshold : distribution ratio between fast & interleaved channels for available excess bit rate Vendor ID : maximum transmission delay allowed by interleaving process

Version number : minimum rates for ATU-C/R Serial number : maximum rates for ATU-C/R 120>Match the following

ADSL line status : initialization failure of ATU-R from ATU-C

Alarms thresholds : event generation upon rate changes when shift margis are crossed in both upstream and downstream

unable to initialize ATU-R : indicates operational status and various types of failures of the link rate change : generates alarms on failures or crossing of thresholds

121>Match the following

line attenuation : 15 min/1 day failure statistics

noise margin : transmit delay introduced by the interleaving process total output power : rate of modem before the last change

maximum attainable rate : data block on which the CRC check is done

current rate : current transmit rate to which the modem is adopted previous rate : maximum currently attainable data rate by modem channel data block length : total output power from the modem

interleave delay : measured power loss in dB from transmitter to receives ATU Statistics : noise margin in dB of the ATU with respect to received signal

122>The ADSL forum has proposed integrating ADSL MIB with the standard IETF interaces group MIB2 interfaces, ifMIB, and transmission in the following manner

a: adslPhysIf: : {transmission 94}

b: adslIterIf: : ={transmission 124}

c: adslFastIf: : ={transmission 125}

Ans: __________ (a/b/c/all) 123>LCS stands for__________

124>___________access technology is primarily focused on bringing multimedia services to residence (narrowband/broadband)

125>___________carrier information from the head end to the customer premises via fiber optic and coaxial cables (DSL/HFC)

ANSWERS

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