Description : Baseband transmission of adigital signal is possible only if wehave a ____channel. A) low-pass B) bandpass C) low rate D) high rate
Last Answer : ow-pass
Description : For a ______ channel, we need to use the Shannon capacity tofind the maximum bit rate. A) noisy B) noiseless C) bandpass D) low-pass
Last Answer : noisy
Description : For a ______ channel, the Nyquist bit rate formula defines thetheoretical maximum bit rate. A) noisy B) noiseless C) bandpass D) low-pass
Last Answer : noiseless
Description : Demodulation is the process of A. converting digital signals toanalog signals B. converting analogsignals todigital signals C. combining many low speed channels into onehigh speed channel D. dividing the high-speed signals into frequency bands E. None of the above
Last Answer : converting analogsignals todigital signals
Description : Which of the following statement is False about the efficiency of the given channel? a. If we want to send big packets on the channel, then Stop and Wait is good choice. b. If length ... is directly proportional to efficiency of channel. d. Efficient might be less if capacity of channel is high
Last Answer : Distance between sender and receiver is directly proportional to efficiency of channel.
Description : Analog-to-analog conversionis needed if the available bandwidthis _______. A) low-pass B) band-pass C) either (a)or (b) D) neither (a) nor (b)
Last Answer : band-pass
Description : Which protocols adopted the standards of HDLC (High Level Link Control) protocol? a. X.25 protocol as LAPB (Link Access Procedure Balanced, V.42 protocol as LAPM (Link Access Procedure for ... Services Digital Network) protocol as LAPD (Link Access Procedure on D channel) d. All the above
Last Answer : d. All the above
Description : A single channel is shared by multiple signals by _____ a. analog modulation b. digital modulation c. multiplexing d. phase modulation
Last Answer : c. multiplexing
Description : _____ isa digital multiplexing technique for combiningseveral low-ratechannels into onehigh-rate one. A) FDM B) TDM C) WDM D) None of the above
Last Answer : TDM
Description : In SMTP mail transaction flow, the sender SMTP establishes a TCP connection with the destination SMTP and then waits for the server to send a ………. a. 220 service ready message b. 421 service not available message c. Both of the above d. None of the above
Last Answer : c. Both of the above
Description : The purpose of stacking elements on an antenna. A. Sharper directional pattern B. increased gain C. Improved bandpass D. All of these
Last Answer : D. All of these
Description : The satellite communications channels in a transponder are defined by the A. LNA B. bandpass filter C. mixer D. input signals
Last Answer : B. bandpass filter
Description : Define Bandpass filter.
Last Answer : The bandpass filter is the combination of high and low pass filters, and this allows a specified range of frequencies to pass through.
Description : What method provides the widest bandpass?
Last Answer : A swamping resistor in parallel with the tuned circuit.
Description : A noiseless 3 KHz Channel transmits bits with binary level signals. What is the maximum data rate? A. 3 Kbps B. 6 Kbps C. 12 Kbps D. 24 Kbps
Last Answer : 6 Kbps
Description : Four channels are multiplexed using TDM. If each channel sends 100 bytes/second and we multiplex 1 byte per channel, then the bit rate for the link is __________. a. 400 bps b. 800 bps c. 1600 bps d. 3200 bps
Last Answer : d. 3200 bps
Description : Suppose transmission rate of a channel is 32 kbps. If there are ‘8’ routes from source to destination and each packet p contains 8000 bits. Total end to end delay in sending packet P is _____. a. 2 sec b. 3 sec c. 4 sec d. 1 sec
Last Answer : a. 2 sec
Description : A device is sending out data at the rate of 2000 bps. How long does it take to send a file of 1,00,000 characters ? a. 50 b. 200 c. 400 d. 800
Last Answer : c. 400
Description : HDLC isan acronym for _______. A) High-duplex line communication B) High-leveldata link control C) Half-duplex digital link combination D) Hostdouble-level circuit
Last Answer : High-leveldata link control
Description : Demodulation is aprocessof A. converting analog to digital signals B. converting digital to analogsignals C. multiplexing various signals intoone high speed line signals D. performing data description
Last Answer : converting analog to digital signals
Description : The channel in the data communication model can be a. postal mail services b. telephone lines c. radio lines d. any of the above
Last Answer : any of the above
Description : A remote batch-processing operation in which data is solely input to a central computer would require a. telegraphp line b. simplex lines c. mixed bad channel d. all of above
Last Answer : simplex lines
Description : Which of the following communications lines is best suited to interactive processing applications? a. narrow band channel b. simplex lines c. full duplex lines d. mixed band channels
Last Answer : full duplex lines
Description : Most data communications involving telegraph lines use: a. simplex lines b. wideband channel c. narrowband channel d. dialed service
Last Answer : narrowband channel
Description : Which of the following types of channels moves data relatively slowly? a. wide band channel b. voice band challen c. narrow band channel
Last Answer : narrow band channel
Description : Which of hte following is considered a broad band communication channel? a. coaxial cable b. fiber optics cable c. microwave circuits d. all of above
Last Answer : all of above
Description : In_______, the stations share thebandwidth of the channel in time. A) FDMA B) TDMA C) CDMA D) none of the above
Last Answer : TDMA
Description : The word______ refers to the portion of a _______ that carriesa transmission. A) channel; link B) link; channel C) line; channel D) line; link
Last Answer : channel; link
Description : Each ________in a SONET framecancarry a digitized voice channel. A) bit B) byte C) frame D) none of the above
Last Answer : byte
Description : In _______ transmission, the channel capacity is shared byboth communicatingdevices at all times. A) simplex B) half-duplex C) full-duplex D) half-simplex
Last Answer : full-duplex
Description : Which of the following types of channels moves data relatively slowly? A. widebandchannel B. voice band channel C. narrowband channel D. broadbandchannel E. None of the above
Description : Carrier is A. One or more conductors that serve as a common connection for a related group of devices B. a continuous frequency capableof being modulated or impressed witha second signal C. ... that provides a data communications service among stations attached tothe network E. None of the above
Last Answer : a continuous frequency capableof being modulated or impressed witha second signa
Description : A remote batch-processing operation in which datais solely input toa central computer would requirea: A. telegraphline B. simplex lines C. mixed-band channel D. All the above E. None of the above
Description : Contention is A. One or more conductors that serve as a common connection for a related group of devices B. a continuous frequency capableof being modulated or impressed witha second signal C. ... that provides a data communications service among stations attached tothe network E. None of the above
Last Answer : the condition whentwo or more stations attempt to use the same channel at the same time
Description : FCP stands for _________ a. Fiber Channel Protocol b. Field Channel Protocol c. Fast Channel Protocol d. Fiber Carrying Protocol
Last Answer : a. Fiber Channel Protocol
Description : A pure ALOHA Network transmits 200 bit frames using a shared channel with 200 Kbps bandwidth. If the system (all stations put together) produces 500 frames per second, then the throughput of the system is ______. a. 0.384 b. 0.184 c. 0.286 d. 0.58
Last Answer : b. 0.184
Description : A certain population of ALOHA users manages to generate 70 request/sec. If the time is slotted in units of 50 msec, then channel load would be a. 4.25 b. 3.5 c. 350 d. 450
Last Answer : b. 3.5
Description : In an Ethernet local area network, which one of the following statements is TRUE ? a. A station stops to sense the channel once it starts transmitting a frame. b. The purpose ... collision is detected. d. The exponential backoff mechanism reduces the probability of collision on retransmissions
Last Answer : The exponential backoff mechanism reduces the probability of collision on retransmissions
Description : For pure ALOHA, the maximum channel utilization is a. 100% b. 50% c. 36% d. 18%
Last Answer : d. 18%
Description : Which of the following is the multiple access protocol for channel access control? a. CSMA/CD b. CSMA/CA c. Both CSMA/CD & CSMA/CA d. HDLC
Last Answer : c. Both CSMA/CD & CSMA/CA
Description : The physical layer is responsible for _____ a) line coding b) channel coding c) modulation d) all of the mentioned
Last Answer : d) all of the mentioned
Description : Which type of channel it is where the number of users are stable and the traffic is not bursts? A. static channel B. dynamic channel C. free channel D. both a and c
Last Answer : A. static channel
Description : Which of the following is the multiple access protocol for channel access control? A. CSMA/CD B. CSMA/CA C. Both CSMA/CD & CSMA/CA D. HDLC
Last Answer : C. Both CSMA/CD & CSMA/CA
Description : The types of Unguided transmission channel or media used for LAN are __. A. Twisted Pair Cables B. Coaxial Cables C. Radio Waves D. All the above
Last Answer : C. Radio Waves
Description : Communication channel is shared by all the machines on the network in ________ a) broadcast network b) unicast network c) multicast network d) anycast network
Last Answer : a) broadcast network
Description : Write about Channel Access on links. Multiple Access Techniques Frequency Division Multiple Access
Last Answer : ∙ In frequency-division multiple access (FDMA), the available bandwidth is divided into frequency bands. ∙ Each station is allocated a band to send its data. ∙ When any one frequency level is ... called chips. ∙ Chips will be added with the original data and it can be transmitted through same
Description : What is the minimum number of wires needed to send data over a serial communication link layer? a. 1 b. 2 c. 4 d. 6 e. none of above
Last Answer : 2
Description : In_____, each station is allocateda time slotduring which it can send data. Each stationtransmits its data in itsassigned time slot. A) FDMA B) TDMA C) CDMA D) none of the above
Description : In______, each station is allocated a band to send its data. In other words, each band is reservedfor a specific station,and it belongs to the station all the time. A) FDMA B) TDMA C) CDMA D) none of the above
Last Answer : FDMA
Description : In _______ methods,a stationcannot send unless it hasbeen authorized byother stations. A) random access B) controlledaccess C) channelization D) none of the above
Last Answer : controlledaccess