DOEACC Society 2006 DOEACC B Level B3.5 Networking

B3.5-R3: NETWORKING AND MOBILE COMMUNICATIONS
NOTE:
Time: three Hours Total Marks: 100
1.
a) What is a bridge? explain the purpose and advantages of a bridge.
b) elaborate the benefits of spread spectrum? What is frequency-hopping spread
spectrum?
c) discuss the terms Attenuation, Delay, distortion and noise.
d) elaborate the different multiple access technologies for Cellular Systems? discuss any
one of them.
e) If a computer is connected to a wireless LAN then it can communicate with the
Computers in wired LAN. Is the statement true? Justify by giving reasons.
f) discuss the concept of interfaces and services. What is the relation ranging from Layers at
an interface?
g) discuss the Circuit-Switched Data Services on Analog Cellular Networks.
(7x4)
2.
a) elaborate the key features of IMT-2000? elaborate the general requirements for Radio
Access to IMT-2000?
b) elaborate the main elements of GSM System architecture? explain the reasons of
separate MS and SIM in GSM.
c) A network is to be planned using cellular topology. If total available bandwidth is 25MHz
and every user requires 30KHz bandwidth for voice communication. 20 lower power
antennas are used and the frequency band is divided in to 4 sets and 1 set is
assigned to every cell. obtain the number of simultaneous users.
(6+6+6)
3.
a) explain the advantages and disadvantages of packet switching over circuit switching?
b) explain the deployment problems with Wireless Local Loop (WLL). discuss Satellite based
technology for WLL Systems.
(6+12)
4.
a) Using QPSK modulation and convolutional coding, the IS-95 digital cellular systems
require 3dB < Sr < nine dB. The bandwidth of the channel is 1.25 MHz., and the
transmission rate is R = 9600 bps. obtain the capacity of a single cell IS-95 cell.
b) i) What is the maximum throughput of a pure ALOHA network with large number of
users and transmission rate of 1Mbps?
ii) What is the throughput of a TDMA network with transmission rate of 1Mbps?
iii) What is the throughput of the ALOHA network if only 1 user was effective
with
transmission rate of 1Mbps?
c) elaborate the security requirements of wireless networks?
B3.5-R3 Page one of two July, 2006
1. ans ques. one and any 4 ques. from two to 7.
2. Parts of the identical ques. should be answered together and in the identical
sequence.
(6+6+6)
B3.5-R3 Page two of two July, 2006
5.
a) What is mobile IP? Draw & define the mobile IP architecture and its functional
components.
b) What is VSAT? elaborate the services supported by VSAT networks?
(12+6)
6.
a) What is GPRS? define the GPRS architecture and protocols.
b) discuss every of the subsequent in detail with reference to WAP:
i) Wireless Datagram Protocol
ii) Wireless Transaction Protocol
iii) Wireless Session Protocol
(12+6)
7. Write short notes on the following:
a) Blue tooth Protocol stack
b) Comparison ranging from OSI reference model and TCP/IP suite
c) Traditional and mobile transport layer
(6x3)
B3.5-R3 Page three of two July, 2006

Earning:   Approval pending.