UNIVERSITY EXAMINATIONS: 2013/2014
ORDINARY EXAMINATION FOR THE BACHELOR OF SCIENCE
IN INFORMATION COMMUNICATION TECHNOLOGY
BSICT 1201 PRINCIPLES OF DATA COMMUNICATIONS
DATE: DECEMBER, 2014 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE: 30 MARKS (COMPULSORY)
a) Define the term computer network according to IEEE. (2 Marks)
b) Explain the following modes of transmission . (4 Marks)
i) Half-duplex
ii) Full-duplex transmission
c) Differentiate between encoding and modulation. (4 Marks)
d) With help of a diagram explain the basic communication model. (5 Marks)
e) What are the benefits of having computer networks (5 Marks)
f) Explain four performance parameters of transmission media. (4 Marks)
g) Explain the following network devices stating in which layer of the OSI model they
operate.
i) Bridges (2 Marks)
ii) Router (2 Marks)
iii) Gateways (2 Marks)
QUESTION TWO: 20 MARKS
a) Define the following types of networks. (6 Marks)
i) Metropolitan Network (MAN)
ii) Wide Area Network (WAN)
iii) Virtual Private Network (VPN)
b) Define the ISO OSI reference Model (3 Marks)
c) In the OSI reference model, explain the concept of data encapsulating and de-encapsulation. (4 Marks)
d) Explain what happens to a piece of data at the presentation layer of the OSI reference model (5 Marks)
e) At the data link layer a trailer is added. What does it contain and what is its use.
(2
Marks)
QUESTION 3: 20 MARKS
a) Explain the following types of errors, stating what causes them and how to prevent
them. (6 Marks)
i) echo
ii) attenuation
b) By the help a diagrams, explain the following types of multiplexing techniques
(6
Marks)
i) Frequency Division Multiplexing(FDM)
ii) Time Division Multiplexing (TDM)
c) Explain the following circuit configuration. (6 Marks)
i. Point-to-point
ii. Multipoint
d) Give two uses and dangers of the Internet (2 Marks)
QUESTION 4: 20 MARKS
a) What is TCP/IP protocol suite? (4 Marks)
b) Explain three features of TCP/IP that make it popular (4 Marks)
c) State and explain any four general Ethernet features. (8 Marks)
d) Differentiate between logical and physical network topologies. (4 Marks)
QUESTION 5:20 MARKS
a) Explain the characteristics of the following types of networks (4 mark)
(i) LAN (Local Area Network)
(ii) MAN (Metropolitan Area Network)
b) Discuss the features of fiber optic cable and their functionality. (3 Marks)
c) Differentiate between the single and multimode fiber optic cable in their features and
functionality. (4 Marks)
d) State and explain six components of a network. (6 Marks)
e) Briefly explain the following LAN models. (3 Marks)
(i) Client-Server
(ii) Peer to Peer
