Muhammad Rizwan Ramay Bc Chichawatni Campus Date 24/7/ Checksums use arithmetic.

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1 1. Checksums use arithmetic. A) ne's cmplement arithmetic B) tw's cmplement arithmetic C) either (a) r (b) 2. The checksum f 1111 and 1111 is. A) 0000 B) 1111 C) 1110 D) In mdul-11 arithmetic, we use nly the integers in the range, inclusive. A) 1 t 10 B) 0 t 10 C) 1 t In cyclic redundancy checking, the divisr is the CRC. A) ne bit less than B) ne bit mre than C) The same size as 5. The between tw wrds is the number f differences between crrespnding bits. A) Hamming rule B) Hamming cde C) Hamming distance 6. The f a plynmial is the highest pwer in the plynmial. A) range B) pwer C) degree 7. In mdul-2 arithmetic, give the same results. A) additin and subtractin B) additin and multiplicatin C) additin and divisin 8. In cyclic redundancy checking, what is the CRC?

2 A) The qutient B) The dividend C) The divisr D) The remainder 9. Which errr detectin methd cnsists f just ne redundant bit per data unit? A) CRC B) Checksum C) Simple parity check D) Tw-dimensinal parity check 10. In cding, we divide ur message int blcks, each f k bits, called. A) blck; blckwrds B) blck; datawrds C) linear; datawrds 11. A errr means that tw r mre bits in the data unit have changed. A) burst B) duble-bit C) single-bit 12. Adding 1 and 1 in mdul-2 arithmetic results in. A) 0 B) 1 C) In errr crrectin, the receiver crrects errrs withut requesting retransmissin. A) nward B) frward C) backward 14. If the Hamming distance between a datawrd and the crrespnding cdewrd is three, there are bits in errr. A) 5 B) 4 C) 3

3 15. A simple parity-check cde can detect errrs. A) an dd-number f B) an even-number f C) tw D) n errrs 16. The Hamming distance between equal cdewrds is. A) 0 B) 1 C) n 17. In a linear blck cde, the f any tw valid cdewrds creates anther valid cdewrd. A) ANDing B) XORing C) ORing 18. In errr crrectin, the receiver asks the sender t send the data again. A) frward B) backward C) retransmissin 19. We can divide cding schemes int tw brad categries: and cding. A) linear; nnlinear B) blck; cnvlutin C) blck; linear 20. In mdul-2 arithmetic, we use nly. A) 1 and 2 B) 0 and 1 C) 0 and T guarantee crrectin f up t 5 errrs in all cases, the minimum Hamming distance in a blck cde must be. A) 11 B) 6 C) 5

4 22. The f errrs is mre difficult than the. A) detectin; crrectin B) crrectin; detectin C) creatin; crrectin D) creatin; detectin 23. In blck cding, if k =2 and n =3, we have invalid cdewrds. A) 4 B) 8 C) The checksum f 0000 and 0000 is. A) 0000 B) 1111 C) 0111 D) In ne's cmplement arithmetic, if psitive 7 is 0111, then negative 7 is. A) 1101 B) 1000 C) In blck cding, if n = 5, the maximum Hamming distance between tw cdewrds is. A) 5 B) 3 C) Which errr detectin methd uses ne's cmplement arithmetic? A) Checksum B) CRC C) Simple parity check D) Tw-dimensinal parity check 28. The divisr in a cyclic cde is nrmally called the. A) redundancy B) degree C) generatr 29. In mdul-2 arithmetic, we use the peratin fr bth additin and subtractin.

5 A) OR B) XOR C) AND 30. We add r redundant bits t each blck t make the length n = k + r. The resulting n-bit blcks are called. A) cdewrds B) datawrds C) blckwrds 31. T guarantee the detectin f up t 5 errrs in all cases, the minimum Hamming distance in a blck cde must be. A) 11 B) 5 C) A generatr that cntains a factr f can detect all dd-numbered errrs. A) x B) 1 C) x cdes are special linear blck cdes with ne extra prperty. If a cdewrd is rtated, the result is anther cdewrd. A) Cnvlutin B) Cyclic C) Nn-linear 34. The Hamming distance between 100 and 001 is. A) 0 B) 1 C) 2

6 1. T use a cable netwrk fr data transmissin, we need tw key devices: a and a A) CT; CMTS B) CM; CMTS C) CM; CMS 2. A lcal telephne netwrk is an example f a netwrk. A) packet-switched B) message-switched C) circuit-switched 3. A traditinal cable TV netwrk transmits signals. A) dwnstream B) upstream C) upstream and dwnstream 4. The traditinal cable TV system used cable end t end. A) twisted-pair B) fiber-ptic C) caxial 5. The telephne netwrk is made f majr cmpnents. A) 4 B) 3 C) 2 6. Data frm a cmputer are ; the lcal lp handles signals. A) analg; analg B) digital; digital C) digital; analg D) analg; digital 7. The riginal telephne netwrk, which is referred t as the plain ld telephne system (POTS), was an system. A) analg B) digital C) digital as well as analg D) nne f the abve

7 8. The prtcl that is used fr signaling in the telephne netwrk is called. A) SSS B) SS7 C) POP 9. technlgy is a set f technlgies develped by the telephne cmpanies t prvide high data rate transmissin. A) LDS B) ASL C) DSL 10. The lcal lp has cable that cnnects the subscriber telephne t the nearest end ffice. A) fiber-ptic B) caxial C) twisted-pair 11. The secnd generatin f cable netwrks is called a(n) netwrk. A) HCF B) HFC C) CFH 12. The largest prtin f the bandwidth fr ADSL carries. A) upstream data B) dwnstream data C) cntrl data D) vice cmmunicatin 13. is suitable fr businesses that require cmparable upstream and dwnstream data rates. A) SDSL B) ADSL C) VDSL D) (b) and (c) 14. The carrier that handles intra-lata services is called a(n). A) IXC B) LEC C) POP

8 15. DMT is a mdulatin technique that cmbines elements f and. A) FDM; QAM B) FDM; TDM C) PSK; FSK D) QDM; QAM 16. The carrier that handles inter-lata services is called a(n). A) IXC B) LEC C) POP 17. The mdern telephne netwrk is nw. A) digital B) digital as well as analg C) analg 18. In an HFC netwrk, the upstream data are mdulated using the mdulatin technique. A) ASK B) PCM C) QAM D) QPSK 19. was designed as an alternative t the T-1 line. A) ADSL B) HDSL C) VDSL D) SDSL 20. HDSL encdes data using. A) 2B1Q B) 1B2Q C) 4B/5B D) 6B/8T 21. In an HFC netwrk, the dwnstream data are mdulated using the mdulatin technique. A) PCM B) QAM C) PSK

9 D) ASK 22. Anther name fr the cable TV ffice is the. A) head end B) cmbiner C) fiber nde D) splitter 23. The term mdem is a cmpsite wrd that refers t the tw functinal entities that make up the device: a signal and a signal. A) demdulatr; mdulatr B) mdulatr; demdulatr C) mdern; dem 24. The tw mst cmmn digital services are service and. A) switched/56; DDS B) switched/56; switched/64 C) DDS; swiched 64 D) leased; ut-f-band 25. The United States is divided int many. A) IXCs B) LECs C) LATAs 26. The standard fr data transmissin ver an HFC netwrk is called. A) ADSL B) CMTS C) DOCSIS D) MCNS 27. In signaling, a prtin f the bandwidth is used fr signaling and anther prtin fr data. A) mixed B) in-band C) ut-f-band 28. Telephne cmpanies prvide tw types f analg services: analg services and analg services. A) leased; ut-f-band B) ut-f-band; in-band

10 C) switched; in-band D) switched; leased 29. The HFC netwrk uses cable. A) caxial B) twisted-pair C) fiber-ptic D) a cmbinatin f (a) and (c) 30. In signaling, the same circuit is used fr bth signaling and data. A) mixed B) ut-f-band C) in-band 31. Mst ppular mdems available are based n the standards. A) X-series B) V-series C) VX-series 32. In G-Back-N ARQ, if 5 is the number f bits fr the sequence number, then the maximum size f the receive windw must be. A) 1 B) 15 C) 16 D) In G-Back-N ARQ, if frames 4, 5, and 6 are received successfully, the receiver may send an ACK t the sender. A) 6 B) 7 C) 5 D) any f the abve 34. The Stp-And-Wait ARQ, G-Back-N ARQ, and the Selective Repeat ARQ are fr channels. B) nisy A) niseless C) either (a) r (b) D) neither (a) nr (b) 35. The Prtcl, adds a simple errr cntrl mechanism t the Prtcl. A) Selective Repeat ARQ; G-Back-N ARQ

11 B) G-Back-N ARQ; Stp-and-Wait C) Stp-and-Wait ARQ; Stp-and-Wait 36. In PPP, the is respnsible fr establishing, maintaining, cnfiguring, and terminating links. A) PAP B) CHAP C) LCP D) NCP 37. HDLC is an acrnym fr. A) Half-duplex digital link cmbinatin B) Hst duble-level circuit C) High-duplex line cmmunicatin D) High-level data link cntrl 38. In Selective Repeat ARQ, if 5 is the number f bits fr the sequence number, then the maximum size f the receive windw must be. A) 1 B) 15 C) 16 D) In G-Back-N ARQ, if 5 is the number f bits fr the sequence number, then the maximum size f the send windw must be. A) 1 B) 15 C) 16 D) In Stp-and-Wait ARQ, the acknwledgment number always annunces in arithmetic the sequence number f the next frame expected. A) mdul-m B) mdul-2 C) mdul In Selective Repeat ARQ, if 5 is the number f bits fr the sequence number, then the maximum size f the send windw must be. A) 1 B) 15 C) 16

12 D) cntrl refers t a set f prcedures used t restrict the amunt f data that the sender can send befre waiting fr acknwledgment. A) Flw B) Errr C) Transmissin 43. In the G-Back-N Prtcl, if the size f the sequence number field is 8, the sequence numbers are in arithmetic, A) mdul-256 B) mdul- 8 C) mdul cntrl refers t methds f errr detectin and crrectin. A) Flw B) Errr C) Transmissin 45. In a G-Back-N ARQ, if the windw size is 63, what is the range f sequence numbers? A) 1 t 63 B) 1 t 64 C) 0 t 63 D) 0 t Bth G-Back-N and Selective-Repeat Prtcls use a. A) sliding windw B) sliding frame C) sliding packet 47. In, the cnfiguratin is balanced. The link is pint-t-pint, and each statin can functin as a primary and a secndary. A) ARM B) ABM C) NBM D) NRM 48. Byte stuffing means adding a special byte t the data sectin f the frame when there is a character with the same pattern as the. A) trailer

13 B) flag C) header 49. The Prtcl has neither flw nr errr cntrl. A) Selective-Repeat ARQ B) G-Back-N ARQ C) Stp-and-Wait D) Simplest 50. The mst cmmn prtcl fr pint-t-pint access is the Pint-t-Pint Prtcl (PPP), which is a prtcl. A) byte-riented B) bit-riented C) character-riented 51. Fr Stp-and-Wait ARQ, fr 10 data packets sent, acknwledgments are needed. A) less than 10 B) mre than 10 C) exactly framing uses tw categries f prtcls: character-riented and bit-riented. A) Standard B) Fixed-size C) Variable-size D) Nne f the abve 53. cntrl refers t a set f prcedures used t restrict the amunt f data that the sender can send befre waiting fr acknwledgment. A) Flw B) Errr C) Transmissin 54. In a prtcl, the data sectin f a frame is a sequence f characters. A) bit-riented B) character-riented C) either (a) r (b) 55. In framing, there is n need fr defining the bundaries f frames.

14 A) standard B) fixed-size C) variable-size 56. The Prtcl has bth flw cntrl and errr cntrl. A) Stp-and-Wait B) Selective-Repeat ARQ C) G-Back-N ARQ D) bth (b) and (c) 57. In, the statin cnfiguratin is unbalanced. We have ne primary statin and multiple secndary statins. A) ARM B) NBM C) NRM D) ABM 58. In a prtcl, the data sectin f a frame is a sequence f bits. A) bit-riented B) byte-riented C) either (a) r (b) 59. In framing, we need a delimiter (flag) t define the bundary f tw frames. A) standard B) fixed-size C) variable-size 60. High-level Data Link Cntrl (HDLC) is a prtcl fr cmmunicatin ver pint-t-pint and multipint links. A) byte-riented B) bit-riented C) character-riented 61. Bit stuffing means adding an extra 0 t the data sectin f the frame when there is a sequence f bits with the same pattern as the. A) trailer B) flag C) header

15 62. In the Prtcl, if n acknwledgment fr a frame has arrived, we resend all utstanding frames. A) G-Back-N ARQ B) Selective-Repeat ARQ C) Stp-and-Wait ARQ 63. The Simplest Prtcl and the Stp-and-Wait Prtcl are fr channels. A) niseless B) nisy C) either (a) r (b) D) neither (a) nr (b) 64. The Prtcl has flw cntrl, but nt errr cntrl. A) Selective-Repeat ARQ B) Stp-and-Wait C) Simplest D) G-Back-N ARQ 65. In Stp-and-Wait ARQ, we use sequence numbers t number the frames. The sequence numbers are based n arithmetic. A) mdul-m B) mdul-2 C) mdul In the Prtcl, the sender sends its frames ne after anther with n regard t the receiver. A) Simplest B) Selective-Repeat ARQ C) Stp-and-Wait D) G-Back-N ARQ 67. cntrl in the data link layer is based n autmatic repeat request, which is the retransmissin f data. A) Flw B) Errr C) Transmissin 68. In PPP, is a three-way hand-shaking authenticatin prtcl in which the passwrd is kept secret; it is never sent nline. A) PAP

16 B) LCP C) NCP D) CHAP 69. In PPP, is a simple authenticatin prcedure with a tw-step prcess: A) CHAP B) PAP C) LCP D) NCP 70. In the prtcl we avid unnecessary transmissin by sending nly frames that are crrupted. A) Selective-Repeat ARQ B) Stp-and-Wait ARQ C) G-Back-N ARQ 71. In prtcls, we use. A) byte-riented; bit stuffing B) bit-riented; bit stuffing C) character-riented; bit stuffing 72. In the Prtcl, the sender sends ne frame, stps until it receives cnfirmatin frm the receiver, and then sends the next frame. A) Simplest B) Stp-and-Wait C) Selective-Repeat ARQ D) G-Back-N ARQ 73. Stp-and-Wait ARQ is a special case f G-Back-N ARQ in which the size f the send windw is. A) 1 B) 2 C) ARQ stands fr. A) Acknwledge repeat request B) Autmatic retransmissin request C) Autmatic repeat quantizatin D) Autmatic repeat request

17 75. in the data link layer separates a message frm ne surce t a destinatin, r frm ther messages ging frm ther surces t ther destinatins. A) Cntrlling B) Framing C) Digitizing 76. Data link cntrl deals with the design and prcedures fr cmmunicatin. A) nde-t-nde B) prcess-t-prcess C) hst-t-hst 77. In prtcls, we use. A) bit-riented; character stuffing B) character-riented; bit stuffing C) character-riented; byte stuffing D) nne f the abve

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