lThis questio n paper contains 8 printed pag cs.
Your Roll No ......... ..... .
Sr. No. of Question Pnpcr : 45 11 G
Uni que Paper Co de 323 41 303
Name of the Paper Computer Networks
Name of the Course B.Sc. (Hons) Computer
Science
Semester III
Duration : 3 Hours Maximum Marks : 75
\I - Instr uctions for Candidates
1. Write your Roll No. on the top immediately on receipt
of this question paper.
2. Section A is compulsory and carries 35 marks.
3. Attempt any 4 Questions from Section B.
Section A
I. (a) What is telecommunication? Assume six devices
are arranged in a mesh topology. How many
cables are needed? How many ports are needed
for each device? ( l +2)
P .T .O .
A/4 ? ,
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(b) What is QPSK?• Giv
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4-QAM . . e ac
onst ella tion diag r am for (1) NRZ-1
(I+ I) (4)
(2) Manchester Encoding
(c) Give any tw o services
. (g) Exp lain the prin cipl e beh ind the
provided th wor king of optical
laye rs : by e follo win g
fiber cable?
(2)
( 1)
(I) Physical Layer (h) What is Flow Control?
(2) Application La yer
. (i) Diff eren tiate betw een pack et swit
(4) chin g and circ uit
( d) Given a n01• seless channel swit chin g. Giv e one app lica tion of
with each . (2 + l )
300 0 Hz transmittin . a band wid th of
g a signal with t .
calc ulat e the . wo s,gnal levels (j) Brie fly desc ribe pigg ybac king
maximum b1't rate. ? Wha t happ ens if
(2)'
the rece iver wants to ackn owl edge
a frame without
(e) Con
. sider a synchronous TDM system
w·th . any data to be sent to the orig inal
mes . Giv en th send er? (l + I)
I at the duration of . ' n mpu t
expl ain th . mpu t frame is T
e workmg of th.is system
with a d'iagram., (k) What is the resu lt of appl ying
zero com pres sion
(2+ 1) on the following !Pv6 addr ess fE&o
:0000: Q000:0000:
QOOO:JlC21:000o:FFFf
(I)
(f) Draw the d.1g1t
. al waveform
following
e d' s to represent the
Assume th nco mg schemes fior the (1) Dist ance vect or rout ing suff ers
data JO JO JO 11. from •cou nt to
at the last sign
. al level is positive. infinity problem". Briefly discuss
the count to
(2)
infinity problem with an example.
P.T .0.
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45 ti
\m) rnu mrrntc the three parts of a Unifo 1111
. Rcsou . (2)
(d) State the optima lity pr inciple .
') G' . ice
Ll'l' ator . 11ve a smtable example.
(J)
Wh · h 3 (a) Differentiate betw een :
\n) at is t e purpose of MF and DF fla . .
g bits With
respect to IP header? (3)
(2) (i) Microwave and Infrared
(2)
(o) \nat is the significance of using g uar d bands? (ii) FSK and PSK
(I) (2)
(iii) Gateway and Router
(b) What are the three address categories to wh ich
Section B
an 1Pv6 address may belong? Explain each of them
(3)
2. briefly.
(a) A bit string, 11101111011111011111101.
transmitted at Data L. k L Is to be
m ayer wh t.
actually transmitted f . , a IS the string ' (a) Generate even parity Hamming Code for data bits
a ter bit stuffing? 4.
(2) (J)
1100100. Show the steps.
(b) Wh at is
· subnet( ?
mg· A router in .
receives a k an orgamzation
pac et with the . (b) Differentiate between Static and Dynam ic Routing
190.240.34 95 destmation address
. . If the subnet mas . Algorithms with the help of an exampk. (3)
the subnet add k IS / 19. Find
ress .
(3) (c) Explain the working of the Sdc~tive Repeat
Protocol with the help of a tfow diagram for the
<q Give.
any three d'ffi
• I erences betw .
and datagram b een virtual circuit following scenarios .
su net.
(3) P.T. 0.
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6
45 11 . ' t aI .signals , baseline wandering
to d1g1
(i) Success ful communication
) In reference f the recei ver to decode the
(c . d'fficult or
rnakeS it t . (2)
tii) lost acknowledgment tly Justify.
(2+2) . nal correc .
s1g
5. k was bu1·1 t w1'th the routers in the
(a) Describe the User Datagram Protocol header with (d) A given networ d A B C, D and E.
epresen t e d as no es ' ' h
the help of a diagram. k
networ r h repre sent t e
(5) · the grap
The edges 10 the routers. Each edge
. . n link between ..
commu01cat10 . the link. Csmg
(b) Briefly describe the one persistent, non-persistent st of traversing
is labelled by the co .thm find shortest
and p-persistent CSMA protocols.
(3) ' hortest path algon '
Dijkshtra s s
(c) Name the protocols associated with the following path from A to C.
port numbers:
(i) 80 B
(ii) 23 A
(2)
6. (a) Differentiate between Bit Rate and Baud Rate
with a suitable example.
(2)
D (-0
(bJ What is the sig nificance of ARP and RARP
protocols? (2)
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7. (a) Explain the process of connection esta blis hme
nt ·
and con nec tion rele ase pro cess use d for
Transmission Control Protocol. (3+2)
(b) To detect a d-bit error you need a distance d+l
code. Justify the statement. (3)
(c) What is the use of options field in the Inte rnet
Protocol Header? Explain with the help of an
example
(2)
(1000)
