UNIVERSITY EXAMINATIONS: 2011/2012
FIRST YEAR EXAMINATION FOR THE BACHELOR OF SCIENCE
IN INFORMATION TECHNOLOGY
BIT 1305 COMPUTER NETWORKS
DATE: JULY, 2012 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE
a) Define the following terms as they are used in computer networks:
i. Transmission [1 Mark]
ii. End system [1 Mark]
iii. Backbone [1 Mark]
iv. Telecommunication [1 Mark]
b) Briefly discuss the following building blocks of a computer network.
i. Network electronics
ii. Software
iii. Network Architecture Standards
[6 Marks]
c) Discuss at least three (3) services that networks provide for people. [6 Marks]
d) “High reliability” and “Financial Implications” are two motivations for setting
up computer networks. Briefly discuss them. [4 Marks]
e) There are various ways in which computer networks can be categorised or
classified including “Message capacity”. Discuss this categorization. [3 Marks]
f) Give at most ONE function of each of the layers in the OSI reference model.
[7 Marks]
QUESTION TWO
a) Given the IP version 4 address 194.138.32.255, identify the following:
i. IP class [1 Mark]
ii. Network address [1 Mark]
iii. Subnet mask [1 Mark]
iv. Host address [1 Mark]
v. What is unique about this address? [1 Mark]
b) With the aid of well-labelled diagrams, differentiate between single-mode and
multi-mode fibre optic cables. [6 Marks]
c) State any five uses for a “crossover cable”. [5 Marks]
d) Differentiate between Local Area Networks (LANs) and Wide Area Networks
(WANs) [4 Marks]
QUESTION THREE
a) Differentiate between the following terminologies as used in computer networks:
i. Broadband and Baseband signaling [2 Marks]
ii. Half duplex and full duplex transmission [2 Marks]
b) Describe briefly five main functions of most Network Operating Systems.
[5 Marks]
c) Discuss any four (4) factors that may influence the choice of a physical network
topology. [8 Marks]
d) Differentiate between a Distributed network and a server–based network.
[3 Marks]
QUESTION FOUR
a) Explain how wireless LANs communicate. [6 Marks]
b) Distinguish the following types of noise:
i. Thermal [1 Mark]
ii. Induced [1 Mark]
iii. Crosstalk [1 Mark]
iv. Impulse [1 Mark]
c) Differentiate between:
i. Logical and Physical network topologies. [2 Marks]
ii. Cut-through switching and store-and-forward switching. [2 Marks]
d) Explain briefly the concept of intranets, extranets and internet. [6 Marks]
QUESTION FIVE
a) Give the functions or applications of the following network troubleshooting
commands:
i. Hostname [1 Mark]
ii. Ipconfig /all [1 Mark]
iii. Ping [1 Mark]
iv. Tracert [1 Mark]
b) List and briefly discuss the functions of any two (2) networking and any two (2)
internetworking devices. [6 Marks]
c) A person wishes to start a family business whose main operation will be
typesetting and laying out publications. His finances allow him to only purchase
two computers, a DeskJet printer and a network ready photocopier. He has
approached you for advice on how he can set up a very basic network connecting
all these devices.
Required:
i. Clearly explain how you would help him set up the network stating what
you would require (in terms of cables, any extras that might be required)
to have the network up and running. [7 Marks]
ii. What solution can you recommend for connection to the internet for this
small company? [3 Marks]
