Description : When 2 or more bits in a data unit has been changed during the transmission, the error is called _____ a. random error b. burst error c. inverted error d. double error
Last Answer : b. burst error
Description : When 2 or more bits in a data unit has been changed during the transmission, the error is called ____________ A. random error B. burst error C. inverted error D. double error
Last Answer : B. burst error
Description : _______ can detect burst error of length less than or equal to degree of the polynomial and detects burst errors that affect odd number of bits. a. Hamming Code b. CRC c. VRC d. None of the above
Last Answer : b. CRC
Description : In______ transmission, wesend1 start bit (0) at thebeginningand 1 or more stop bits (1s) at the end of each byte. A) synchronous B) asynchronous C) isochronous D) none of the above
Last Answer : asynchronous
Description : Let G(x) be the generator polynomial used for CRC checking. What is the condition that should be satisfied by G(x) to detect odd number of bits in error? a. G(x) contains more than two terms b. G(x) does ... exceeding the frame length c. 1+x is a factor of G(x) d. G(x) has an odd number of terms
Last Answer : c. 1+x is a factor of G(x)
Description : How many 8-bit characters can be transmitted per second over a 9600 baud serial communication link using asynchronous mode of transmission with one start bit, eight data bits, two stop bits, and one parity bit ? a. 600 b. 800 c. 876 d. 1200
Last Answer : b. 800
Description : A byte consists of a. One bit b. Four bits c. Eight bits d. Sixteen bits
Last Answer : Eight bits
Description : A band is always equivalent to a. a byte b. a bit c. 100 bits d. none of above
Last Answer : none of above
Description : We addr redundant bits toeach block to make thelength n = k + r. The resultingn-bit blocksare called _________. A) datawords B) blockwords C) codewords D) none of the above
Last Answer : codewords
Description : The ______ technique expands the bandwidthof a signal by replacing each data bit with n bits. A) FDM B) DSSS C) FHSS D) TDM
Last Answer : DSSS
Description : In IPv6,a _________address comprises 80 bits of zero, followed by16 bitsof one, followed by the 32-bit IPv4address. A) link local B) site local C) mapped D) none of the above
Last Answer : mapped
Description : The least significant 23 bits in a 48-bit Ethernet address identify a ________. A) multicast router B) host C) multicast group D) noneof the above
Last Answer : multicast group
Description : A 8-Mbps tokenring has atoken holding timer value of 10 msec. What is the longest frame (assumeheader bits are negligible) that canbe sent on this ring? A. 8000 B frame B. 80,000 B frame C. 8 x 105 bit frame D. 10,000 B frame
Last Answer : 10,000 B frame
Description : Suppose that the one-way propagation delay for a 100 Mbps Ethernet having 48-bit jamming signal is 1.04 micro-seconds. The minimum frame size in bits is: a. 112 b. 160 c. 208 d. 256
Last Answer : d. 256
Description : We add r redundant bits to each block to make the length n = k + r. The resulting n-bit blocks are called _________ A. datawords B. blockwords C. codewords D. none of the above
Last Answer : C. codewords
Description : Let C be a binary linear code with minimum distance 2t + 1 then it can correct upto _____ bits of error. a. t + 1 b. t c. t - 2 d. t / 2
Last Answer : b. t
Description : . ________ is the process in which the receiver tries to guess the message by using redundant bits A. Connection-Oriented Service B. Forward error correction C. both a and b D. Confirm
Last Answer : B. Forward error correction
Description : The original ASCII code used…bits of each byte, reserving that last bit for error checking a. 5 b. 6 c. 7 d. 8
Last Answer : c. 7
Description : Which error detection method consists of just one redundant bit per data unit? A) Simple parity check B) Two-dimensionalparity check C) CRC D) Checksum
Last Answer : Simple parity check
Description : Which of the following is associated with error detector? a. Odd parity bit b. Even parity bit c. Both of the above d. None of above
Last Answer : Both of the above
Description : Error detection ata data link level is achieved by A. bit stuffing B. cyclic redundancy codes C. Hamming codes D. equalization
Last Answer : cyclic redundancy codes
Description : The probability thata singlebit will be inerror on a typical public telephone lineusing 4800 bps modem is 10 to the power -3. If no error detection mechanism is used, the residual error ratefor a communicationline using 9-bit frames is ... to A. 0.003 B. 0.009 C. 0.991 D. 0.999 E. None of the above
Last Answer : 0.009
Description : In Unix, files can be protected by assigning each one a 9-bit mode called rights bits. Now, consider the following two statements: I. A mode of 641 (octal) means that the owner can read and write the file, other ... (B) Only II is correct (C) Both I and II are correct (D) Both I and II are incorrect
Last Answer : (C) Both I and II are correct
Description : A memory unit stores 2^16 bytes in 32-bit words. How many address bits are necessary in order to retrieve a single word from this memory unit?
Last Answer : Each word is 4 bytes, which occupies 4 consecutive addresses at 16 bits each. The first 14 bits of these addresses will be the same, differing only in the two least significant bits. You only need to specify the first 14 bits, because there are only 2^14 words occupying those 2^16 bytes.
Description : The computer abbreviation KB usually means– (A) Key Block (B) Kernel Boot (C) Key Byte (D) Kit Bit (E) Kilo Byte
Last Answer : Kilo Byte
Description : The term ________ means that IP provides no error checking or tracking. IP assumes the unreliabilityof the underlying layers and does its best to get a transmission throughto its destination,but with ... ) reliable delivery B) connection-oriented delivery C) best-effort delivery D) noneof the above
Last Answer : best-effort delivery
Description : Floppy disks are available in a. Single side single density b. Single side double density c. Both of above d. None of above
Last Answer : Both of above
Description : A _________ sine wave is not useful in data communications; we need to send a _______signal. A) composite; single-frequency B) single-frequency; composite C) single-frequency;double-frequency D) none of the above
Last Answer : single-frequency; composite
Description : The synchronous modems are more costly than the asynchronous modems because a. they produce large volume of data b. they contain clock recovery circuits c. they transmit the data with stop and start bits d. they operate with a larger bandwidth e. none of above
Last Answer : they contain clock recovery circuits
Description : The synchronous modems are more costly than the asynchronous modemsbecause A. they produce largevolumeof data B. they contain clock recovery circuits C. they transmit thedata with stop and start bits. D. they operate witha largerbandwidth E. None of the above
Description : 'Cloud burst' means – (1) Sowing of seeds of a crop in cloudy weather. (2) Abnormally heavy downpour of rain, associated with a thunderstorm. (3) Formation of artificial rain. (4) Presence of scattered flakes of cloud in the sky.
Last Answer : (2) Abnormally heavy downpour of rain, associated with a thunderstorm. Explanation: A cloudburst is an extreme amount of precipitation, sometimes accompanied by hail and thunder, that normally ... . However, cloudbursts are infrequent as they occur only via orographic lift or sudden condensation.
Description : Cloud burst means – (1) Formation of artificial rain (2) Abnormally heavy downpour of rain, associated with thunderstorm (3) Presence of scattered flakes of cloud in the sky (4) Sowing of seeds of a crop in a cloudy weather
Last Answer : (2) Abnormally heavy downpour of rain, associated with thunderstorm Explanation: A cloudburst is sudden copious rainfall. It is a sudden aggressive rainstorm falling for a short period of time limited to a small geographical area. Generally cloudbursts are associated with thunderstorms
Description : ‘Cloud burst’ means (1) Sowing of seeds of a crop in cloudy weather. (2) Abnormally heavy downpour of rain, associated with a thunderstorm. (3) Formation of artificial rain. (4) Presence of scattered flakes of cloud in the sky.
Last Answer : Abnormally heavy downpour of rain, associated with a thunderstorm.
Description : Cloud burst means (1) Formation of artificial rain (2) Abnormally heavy downpour of rain, associated with thunderstorm (3) Presence of scattered flakes of cloud in the sky (4) Sowing of seeds of a crop in a cloudy weather
Last Answer : Abnormally heavy downpour of rain, associated with thunderstorm
Description : The ________ between two words is the number ofdifferences between corresponding bits. A) Hamming code B) Hamming distance C) Hamming rule D) none of the above
Last Answer : Hamming distance
Description : Consider a source computer(S) transmitting a file of size 106 bits to a destination computer (D)over a network of two routers (R1 and R2) and three links(L1, L2, and L3). L1connects S to R1; L2 connects R1 to ... file from S to D? a. 1005 ms b. 1010 ms c. 3000 ms d. 3003 ms Answer: Option(a)
Last Answer : a. 1005 ms
Description : How many bytes of data can be sent in 15 seconds over a serial link with baud rate of 9600 in asynchronous mode with odd parity and two stop bits in the frame? a. 10,000 bytes b. 12,000 bytes c. 15,000 bytes d. 27,000 bytes
Last Answer : b. 12,000 bytes
Description : The distance between two stations M and N is L kilometers. All frames are K bits long. The propagation delay per kilometer is t seconds. Let R bits/second be the channel capacity. Assuming that processing ... maximum utilization, when the sliding window protocol used is: a. A b. B c. C d. D
Last Answer : c. C
Description : The ________ between two words is the number of differences between corresponding bits A. Hamming code B. Hamming distance C. Hamming rule D. none of the above
Last Answer : B. Hamming distance
Description : acode is simply a subset of the vertices ofthe a. n bit b. ncube c. n single d. n double
Last Answer : b. ncube
Description : the storage capacity of a disk system depends on the bits per inch of track and the tracks per inch of a. Cylinder b. Hum c. Cluster d. Surface
Last Answer : Surface
Description : If in a computer, 16 bits are used to specify address in a RAM, the number of addresses will be a. 216 b. 65,536 c. 64K d. Any of the above
Last Answer : 65,536
Description : a computer which CPU speed around 100 million instruction per second and with the word length of around 64 bits is known as a. Super computer b. Mini computer c. Micro computer d. Macro computer
Last Answer : Super computer
Description : Storage capacity of magnetic disk depends on a. tracks per inch of surface b. bits per inch of tracks c. disk pack in disk surface d. All of above
Last Answer : All of above
Description : Number of bits per symbol used in Baudot code is a. 7 b. 5 c. 8 d. 9
Last Answer : 5
Description : Avalanche photodiode receivers can detect bits of transmitted data by receiving a. 100 photons b. 200 photons c. 2000 photons d. 300 photons
Last Answer : 200 photons
Description : In Ethernet addressing, ifall the bits are 1s, the address is _________. A) unicast B) multicast C) broadcast D) none of the above
Last Answer : broadcast