TELECOMMUNICATION SWITCHING NETWORKS

BIT BANK

UNIT 1: MULTIPLEXING

  1. SONET means_____

A) Synchronous optical networkB) Synchronous optical net C) Sync optical network D) None

  1. SONET ring is also known as_____

A) Heating RingB) Self heatingC)Synchronous heatingD) Gained ring

  1. CCIT Means

A)Consultative Committee for International Telephony and Telegraphy

B)Consultative Committee for International Telegraphy and Telephony

C)Consulting Committee for International Telegraphy and Telephony

D)Consultative Committee for International Telemetry and Telephony

  1. In telephone conversion the one who initiates the call is known as

A) Calledsubscriberb) Calling subscriberC) SubscriberD) None

  1. In telephone conversion the one whom the call isdestined is known as

A) Called subscriberb) Calling subscriberC) SubscriberD) None

  1. ECSA Means

A) Exchange carriers system AssociationB) Easy carriers standards Association

C) Exchange carriers standards AssociationD) Exchange carry standards Association

  1. Scrambling the data using scrambling algorithm is known as

A) ScramblingB) Scrambling dataC) Data ScramblingD) None

  1. The carrier bandwidth is divided into sub channels of different frequency widths, each carrying a signal at the same time in parallel is known as

A) frequency-data multiplexingB) time-division multiplexing

C) frequency-division multiplier D) frequency-division multiplexing

  1. The process of converting binary data into a sequence of bits to a digital signal is known as

A) CodingB) Line codingC)Data codingD)Digital coding

  1. ITU Means

A) International Telegraphy unionB)International communication union

C) International Tele- communication unionD) International Telephony union

  1. Telephony set is invented by

A) Alexander GrahamBellB) AlexanderC) FlemingD) None

  1. At the lowest level of the network are class 5 switching offices, also called

A) Central offices B) End offices C) Both A or BD) All the above

  1. One of two basic types of electromechanical switches is

A) Step-by-step B) crossbar C) Both A and B D) All the above

  1. One of the examples of transmission systems are

A) Open wire B) Paired cable C) Micro wave radio links D) all the above

  1. FDM is also utilized in fiber optic transmission systems where it is referred to as

A) Wave length division multiplexing B) Frequency division modulation

C) Time division modulation D)None

  1. All multiplex equipment in the FDM hierarchy used

A) AM modulation B) DSB-SC modulation C) SSB modulation D) FM modulation

  1. Super group has ------of voice circuits

A) 600 B) 6000 C) 6 D) 60

  1. In coaxial cable, a system designation of L1 has ------total capacity

A) 1800 B) 2400 C) 180 D) 700

  1. Microwave radio systems carne from the need to distribute------signals in nationwide

A) Television B) Radio C) Mobile D) line

  1. common-channel signaling (ccs) uses a data link between the ----- switching systems

A) program control elements B) stored-program control elements

C) stored control elements D) control elements

  1. Rmax= 2BW is also known as

A) Nyquist bandwidth B) Nyquist interval C) Nyquist period d) Nyquist rate

  1. Small perturbations in the channel response or the sample times produce nonzero overlap t the sample t time Called as

A) Inter symbol interference B) symbol interference C) Interference D) None

  1. Compensation of phase distortion is referred to as

A) Amplitude distortion B) phase equalization C) Amplitude equalization D) phase distortion

  1. Compensation of amplitude distortion is referred to as

A) Amplitude distortion B) phase equalization C) Amplitude equalization D) phase distortion

  1. No dc wander is the digital biphase code, also referred to as ------code.

A) Diphase B) Manchester C) A or B D) None

  1. Differential encoding that encodes a 1as ------of state and encodes a 0 ------in state

A) A change & no change B) No change & change C) change &change D) No change & no change

  1. The as-needed form of TDM is variously referred to as a------

A) Synchronous time division multiplexing B) Asynchronous time division multiplexing

C) Time division multiplexing D) synchronous multiplexing

  1. Those hat repeatedly assign a position of the transmission capacity to each source is known as

A) Synchronous time division multiplexing B) Asynchronous time division multiplexing

C) Time division multiplexing D) synchronous multiplexing

  1. Each channel is assigned a time slot corresponding to a single bit it is known as------

A) Bit interleaving B) Word Interleaving C) Interleaving D) None

  1. Each channel is assigned a longer time slot corresponding to some larger number of bits

A) Bit interleaving B) Word Interleaving C) Interleaving D) None

  1. ADM means

A) Add drip multiplexerB) Add De- multiplexer C)Add drop multiplexerD) odd drip multiplexer

  1. SDH means

A) Synchronous data hierarchy B) Asynchronous digital hierarchy

C) synchronous digital hierarchy D) None

  1. A SONET system is defined as a hierarchy of three levels------

A) Sections B) lines C) pathsD) All the above

  1. Each sonet frame consists of------rows of------byte

A) 9& 90 B) 90&9 C) 900& 9 D) 9000&900

  1. STS-1 rate =

A) Over head rateB) information envelope rate

C) Overhead rate + information envelope rate D) None

  1. The SONET standard places significant emphasis on the need for------of an end-to-end system

A) Operations B) Administration C) Maintenance D) All the above

  1. Section overhead allocates of------bytes in each STS-1 frame

A) 9B) 99C) 999D)9999

  1. Line overhead allocates of------bytes in each STS-1 frame

A) 8B) 18C) 98 D) 989

  1. The SONET standard uses sub- STS-I payload mappings referred to as ------structures

A) FramesB) payloads C)Virtual tributaryD) None

  1. The bit rate of OC-1 Sonet source is------

A) 51.84 mbpsB) 50.84 mbpsC) 59.84 mbps D) 99.84mbps

UNIT 2: DIGITAL SWITCHING

  1. The control functions in switching system are

A) Event monitoring B) Call processing C) Charging Operation D) All the above

  1. A multidimensional switching that utilizes at least three degrees of------

A) Freedom, B) timeC) wavelength and spaceD) All the above

  1. A process where multiple analog message signals or digital data streams are combined into one signal over a shared medium is also known as

A) Multiplexing B) De-Multiplexing C) Encoder D) Decoder

  1. A------is to set up and release connections between transmission channels

A) Plug B) Switch C) Wire D) None

  1. Each loop must be accessible to every other loop; this level of switching is sometimes referred to as

A) Line switching B) tandem switching C) call distribution D) None

  1. Space division switching matrix can be used to connect anyone of N ------to any one o f M------

A)outlets&outlets B) outlets& inlets C) inlets&inlets D) inlets& outlets

  1. Graded switch structures are no------

A) Longer B) shorter C) Widths D) All the above

  1. In the triangular matrix the------cross points are eliminate

A) Straight B) Left C) redundant D) Right

  1. In multiple stages switching the number of inlet-outlet pairs is equal ------for a triangular array

A) N B) N (N-1)/2 C) 2N D) N2

  1. In multiple stages switching the number of inlet-outlet pairs is equal ------for a square array

A) N B) N (N-1) C) 2N D) N2

  1. The inter stage connections are often called------

A) Junctor B) junction C) cross point D) cross box

  1. If the number of center stages is equal to 2n -1, the switch is strictly

A) BlockingB) Clocking C) Non-blockingD) None

  1. ------switches are rarely needed in most voice telephone networks

A) Non-Blocking B) Clocking C) blockingD) None

  1. The blocking probability is most easily determined as------

A) B=1B) B=1-qC) B=0D) B=1-qn

  1. Multiple-stages witches can be used for either ------wire switching operation

A) 2B) 8C) 4D) A & C

  1. A two-wire connection requires only------path

A) 2B) 1C) 3D) 4

  1. In switch matrix control, the control may be associated with the output lines and which inputs are to be connected to the associated outputs is called as------

A) output-associated control B) input-associated control C) output control D) Input control

  1. The control information may be associated with each input and subsequently specific to which outputs the respective inputs are to be connected is called as

A) output-associated controlB) input-associated controlC) output control D) Input control

  1. In switch matrix control the total number of bits required to specify a connection configuration is ----

A) 2MB) MC) N log2 MD) N/M

  1. Time division switching is equally applicable to either ------signals

A) AnalogB) digitalC) Both A & BD) None

  1. In analog time division switching frame rate is equal to the ------of each line

A) Sample rate B) Nyquist rateC) signaling rateD) None

  1. Switching between time slots represents a second dimension of switching and is refined to as

A) Space switchingB) Time switchingC) TDMD) FDM

  1. A time stage between two space stages is referred to as a ------switch

A) TSTB) STSC) Space switchingB) Time switching

  1. A space stage between two time stages is referred to as a ------switch

A) TSTB) STSC) Space switchingB) Time switching

  1. Complexity of an STS switch as Complexity =------

A) No. of spaces large cross pointsB) no. of space stage control bits+ no. of time stage memory bits

C) No. of time stage control bitsD) A+B+C/100

  1. The blocking probability for a TST switch with non- blocking individual stages (TST) is------

A) qB) B-1C) q-1D) [1-q12]l

  1. A No.4 ESS matrix is time-space-time with ------stages in the space switch

A) 2B) 5C) 1D) 4

  1. The maximum size of the No. 4ESS uses ------de correlators with seven-----channel input

A) 128,120B) 120,128C) 128,128D) 120,120

  1. The system 75 PBX of AT&T was a midrange PBX that can support of ------stations

A) 300B) 400C) 200D) 800

  1. The system 75 PBX of AT&T was a midrange PBX that can support of ------trunks

A) 300B) 400C) 200D) 800

  1. A Digital Cross Connect Systems is basically a------switching matrix

A) AnalogB) DigitalC) BipolarD) None

  1. Advantages of a DCS system is------

A) Automatic Record KeepingB) Remote and Rapid Provisioning

C) Automated Test AccessD) All the above

  1. The primary purpose of the DCS 3/3 is to provide------

A) Network restorationB) protection the DS3 signalC) A & BD) none of the above

  1. A DCS needs to be strictly non-blocking at the------level

A) DSOB) DS1C) DS2D) DS3

  1. BORSCH means------

A)Battery feed over voltage protection Ringing Supervision Coding Hybrid Test

B)Battery Overvoltage protection Ringing Supervision Coding Hybrid Test

C)Battery feed Overvoltage Ringing Supervision Coding Hybrid Test

D)Battery feed Overvoltage protection Ringing Supervision Coding Test

  1. An analog network conference calls are established by merely adding individual signals together using

a conference------

A) RingB) meshC) bridgeD) all the above

  1. The system 75 PBX of AT&T was a midrange PBX that can support of ------instruments

A) 300B) 400C) 200D) 800

  1. The EWSD switch of Siemens uses a ------structure

A) TSSTB) TSTC) STSD) none

  1. A time stage T followed by a space stage S is referred to a------switch

A) TSB) TSTC) STSD) none

  1. Switching between time slot represents a second dimension of switching and is refined to as------

A) Time switchingB) Space switchingC) TSTC) STS

UNIIT-3

  1. All digital systems require______sources for internal and external operations

(A) Frequency (B) Clock(C) Both(D) None

  1. ______is used for synchronizing of receiver clock to transmitter clock

(A) VCO(B) PLL(C) Phase Detector(D) None

  1. The phase detector measures the difference in the _____between the two signals
  2. (A) Crossing (B) Zero crossing (C) VCO (D) None
  3. Voltage controlled oscillator is used to reduce ______difference

(A) Amplitude(B) Frequency(C) Phase(D) None

  1. Clock instability is related to______

(A) Amplitude(B) Frequency(C) Phase(D) None

  1. The small variations in VCO control voltage are referred to as______

(A) Clock(B) Clock wander(C) jitter (D) None

  1. The rapid variations in VCO control voltage are referred to as______

(A) Clock(B) Clock wander(C) jitter(D) None

  1. The main sources of clock instability is_____

(A) Noise (B) length of velocity(C) Doppler shifts(D) All the above

  1. The dividing point between wander and jitter is______HZ

(A) 10(B) 100(C) 1000(D) 1

  1. Geostationary satellites produce path length variations up to______miles

(A) 20(B) 200(C) 2(D) 2000

  1. Doppler shifts occurs due to______

(A) Satellites(B) Aero planes(C) Both A&B(D) None

  1. Jitter power represents______variations

(A) Power(B) Length(C) Width(D) Timing

  1. The analysis of jitter chain is reported by______

(A) Byrne(B) Karafin(C) Robinson(D) All the above

  1. Disruptions in the data stream of an elastic store are referred to as

(A) Slips(B) Slaps(C) store(D) None of the above

  1. An 8-bit slip with a digitized modem uses a carrier signal of______HZ

(A) 18(B) 1800(C) 180(D) 200

  1. Switching interfaces set a slip for every ______hour
  2. (A) 2(B) 22(C) 20(D) 24
  3. ______stuffing is used for avoiding slips and clock synchronization

(A) Ramp (B) Pulse(C) Square(D) sine

  1. The output channel can carry all the input data with a______bits

(A) Null(B) Stuff(C) Both A&B(D) None

  1. Pulse stuffing is also referred to as______in Europe

(A) Slips(B) Synchronization(C) Justification(D) None

  1. If R2> R1 the data is______in bit stream

(A) Lost(B) Inserted(C) Removed (D) None

  1. If R2< R1 the data is ______in bit stream

(A) Lost(B) Inserted(C) Removed (D) None

  1. The lower rate signals are combined into higher level signals is known as___ multiplexing

(A) Synchronous(B) Asynchronous(C) Isochronous(D) None

  1. The difference between the Elastic store input data rate and its output data rate is known as

(A) Slip rate(B) Baud rate(C) Data rate(D) None

  1. A channel bank is connected to a digital switch through T1 lines is known as

(A) T1 bank(B) loop timing(C) Switching(D) All the above

  1. Irregularity in the data arrival rate caused by the gaps is referred as
  2. (A) Jitter(B) Time jitter(C) Waiting time jitter (D) gap jitter
  3. The public telephone network in the United States uses______synchronization

(A) Plesiochronous(B) Mutual(C) packetization(D) network master

  1. The process of passing the reference downward from one level to the next is ___ synchronization

(A) Master(B) Slave(C) Slave-Master (D) Master-Slave

  1. ______Codes are no clock transitions during intervals of binary ‘0’s.

(A)Diphase(B) Manchester(C) Bi-Polar(D) All

  1. Change in the transmission media leads to____

(A)Wander (B) Jitter(C) Clock instability (D) All

  1. The propagation velocity of radio waves in the atmosphere will changes with_____

(A)Temperature(B) Humidity(C) Both(D) None

  1. If no timing discrepancies exist between TDM links and Digital switch is called as__

(A) Loop Timing(B) Synchronization(C) Both(D) None

  1. In TDM Switch interface ______absorbs the clock instabilities

(A)Digital Switch(B) TDM Link(C)Elastic Store(D) All

  1. The average bits sends by each tributary during a maser frame are

(A) 3.5(B)4.5(C)5.3(D)5.4

  1. A DS2 is derived by interleaving _____ Signals
  2. (A) 2DS0(B)2DS1(C)4DS1(D)2DS1+2DS0
  3. A DS2 master frame is _____ bits long

(A) 1167(B) 1176(C) 1116(D) 1166

  1. Total number of synchronisation approaches in a digital network

(A) 6(B)9(C)4(D)5

  1. ______is the measure of difference between TIE Samples

(A)MTIE(B) TVAR(C) TIE(D)TDEV

  1. The difference in delay between a timing signal and ideal timing signal is called as____
  2. (A)MTIE(B) TVAR(C) TIE(D) TDEV
  3. The maximum peak-to-peak variations in TIE are referred as____

(A)MTIE(B) TVAR(C) TIE(D) TDEV

  1. ______can be measured in nanoseconds

(A)MTIE(B) TVAR(C) TIE(D) TDEV

Unit-4

  1. ADSL means

(A) Asymmetric digital subscriber line(B) Asymmetric digital subscriber LAN

(C) Symmetric digital subscriber line(D) None

  1. ISDN Acronym is

(A) Integrated services digital network(B) Integrated services dynamic network

(C) Integrity services digital network(D) None

  1. ______is the type of Digital subscriber lines

(A) DSL(B) ADSL(C) HDSL(D) All the above

  1. The basic rate interface is referred to as ______interface

(A) 2B(B) 3B(C) 2B+D(D) 2D+B

  1. In North America primary rate interface is referred to as ______interface

(A) 2B(B) 23B+D(C) 2B+D(D) 2D+B

  1. The PRI DS1 signal has______Mbps

(A) 1.544(B) 15.44(C) 14.55(D) 16.55

  1. Wireless access can be done by______systems

(A) Microwave distribution systems(B) Multi channel multi point distribution service

(C) BOTH(D) all the above

  1. The data rate of ITU-T PRI is______Mbps

(A) 2.048(B) 20.48(C) 21.40(D) 31.40

  1. The formal rules of Communication between DCE are referred to as------

(A) Protocol(B) DTE(C) DMT(D) None

  1. The transmission technology of BRA is referred to as______

(A) DSL(B) ADSL(C) HDSL(D) SDSL

  1. The reference point U is used to interface______wire transmission line

(A) 3(B) 4(C) 2(D) 5

  1. Time compression multiplex developed by______in Japan

(A) NAC(B) NEC(C) NDA(D) CCA

  1. TCM is also referred to as______transmission

(A) Ping-pong(B) pong-ping(C) Both A&B(D) None

  1. A four level line code is referred to as______code

(A) 2BQ(B) 2B1Q(C) 21Q(D) 21BQ

  1. The symbol rate for four level line code is______symbols/sec

(A) 80,000(B) 8000(C) 85000(D) 95000

  1. The D channel protocol is of______and______series

(A) I, Q(B) I, B(C) Q, Y(D) C, Q

  1. The network layer of the D channel protocol is defined in______

(A) I.451(B) Q.931(C) Both A&B(D) None

  1. Automatic gain control is used to adjust ______level

(A) Transmit (B) Receive(C) Both A&B(D) None

  1. Universal digital loop carrier system can be used to interface ______system

(A) Analog(B) Digital(C) Both A&B(D) None

  1. The second category of FITL is a ______system

(A) FITC(B) FTTC(C) FTTH(D) None

  1. The Third category of FITL is a ______system

(A) FITC(B) FTTC(C) FTTH(D) None

  1. The Coaxial cable portions of CATV systems are configured as_____ topology

(A) Tree(B) Mesh(C) Star(D) None

  1. ISDN is leading the concept of ______Network

(A) Intelligent (B) Broadband (C) Standard (D) None

  1. ISO stands for ______

(A) International Standards Organization (B) International Services Origin.

(C) Integrated standard organization (D) None

  1. Distribution services are classified as Broadcast services and ______services

(A) Retrieval (B) Cyclic (C) Both A&B(D) None

  1. BISDN services are broadly classified as interactive and _____ services.

(A) Cyclic (B) Distribution (C) Both A&B(D) None

  1. The data rate of bearer channel is ____

(A) 16 kbps(B) 64 kbps(C) 24 kbps(D) None

  1. The ______channel can be used for telemetry and alarms

(A) B(B) C(C) D(D) H

  1. ISDN was developed by

(A) ITU-T(B) IEEE(C) IMT(D) T

  1. AT&T and USITA uses------synchronization for switched digital network

(A) Plesiochronous(B) Mutual(C) packetization(D) Master-Slave

  1. In ADSL the upstream and downstream data rates are___

(A) Same(B) Different(C) Constant(D) None

  1. ADSL stands for

(A) Amplitude digital subscriber line(B) Asymmetric digital subscriber line

(C) Analog digital subscriber line(D) Adaptive digital subscriber line

  1. The downstream bandwidth in ADSL is about ______times as wide as upstream direction

(A) 3.5(B) 2.5(C) 4.5(D) 1.5

  1. ADSL uses_____ modulation technique

(A) DCT(B) DET(C) DFT(D) DMT

  1. SDSL stands for ______

(A) Simple digital subscriber line(B) Single line digital subscriber line

(C) Sample digital subscriber line(D) synchronous digital subscriber line

  1. In modem, ______functions are performed

(A) Modulation(B) demodulation(C) modulation and demodulation(D) multiplication

  1. An ANSIU interface frame format contains

(A) 240 bits(B) 420 bits(C) 320 bits(D) 230bits

  1. TMC is used to avoid

(A) near-end crosstalk(B) Far-end crosstalk(C) Co Channel crosstalk(D) None

  1. The Coaxial cable portions of CATV systems are configured as_____ topology

(A) Tree(B) Mesh(C) Star(D) None

Unit-5

  1. The rate at which the traffic enters a network is referred to as______

(A) Flow control(B) network control(C) A& B(D) None

  1. ______provides the basis for the analysis and design of telecommunication networks

(A) Traffic engineering (B) Networks(C) Telegraphs(D) Data networks

  1. In a day, the 60-minute interval in which the traffic is the highest is called the_____

(A) Busy hour (BH) (B) Peak BH (C) Time consistent busy hour(D) All

  1. Average busy hour calls = _____

(A) BHCA+CCR (B) BHCA/CCR(C) BHCA*CCR(D) None

  1. Traffic intensity is measured in _____

(A) Ohms (B) Erlang’s(C) Both (D) None

  1. CCS stands for ------

(A) Century call second (B) Century carry second (C) Both A&B (D) None

  1. Traffic carried per server ______

(A) Occupied duration/Total duration (B) Occupied duration+ Total duration

(C) Occupied duration*Total duration (D) Occupied duration ^ Total duration

  1. Subscriber traffic in Erlang’s ______

(A) Busy period+ Total period (B) Busy period*Total period

(C) Busy period/Total period (D) All

  1. Blocking probability is called -----

(A) Time congestion (B) Call congestion(C) Both A&B (D) None

  1. The delay system is also known as _____

(A) Congestion Theory (B) Queuing Theory(C) Blocking (D) None

  1. GOS stands for ------

(A) Grade of system (B) Grade of service (C) Both (D) None

  1. The delay system is measured in terms of

(A) Service delay (B) Blocking probability(C) Network delay(D) None

  1. In loss systems over load traffic is

(A) Held in Queue (B) rejected(C) Both A&B(D) None

  1. Blocking model is also known as _____

(A) Absorption (B) Reflection(C) Congestion(D) All the above

  1. How is the relation between Erlang’s and CCS specified

(A)Erlang = 36 CCS(B) 1 Erlang = 56 CCS(C)1 Erlang = 76 CCS(D)1 Erlang = 96 CCS

  1. The ratio of number of successful calls to the number of call attempts is known as ______

(A)Busy Hour Call Rate (BHCR)(B) Call Completion Rate (CCR)

(C)Call Block Rate (CBR)(D) None of the above

  1. If a telephone exchange serves 1500 users with the average BHCA of about 9000 and CCR is about 50%, what would be the busy hour calling rate?
  2. (A) 2(B) 3(C) 4.5(D) 5
  3. Percentage of occupancy can be defined as the percentage of _____ for which the server seems to be busy.

(A) speed(B) distance(C) time(D) volume