UNIVERSITY EXAMINATIONS: 2013/2014
ORDINARY EXAMINATION FOR THE BACHELOR OF SCIENCE
IN INFORMATION TECHNOLOGY&BUSINESS INFORMATION
TECHNLOGY
BBIT 103 BIT 1305 COMPUTER NETWORKS
DATE: AUGUST, 2014 TIME: 2 HOURS
INSTRUCTIONS: Answer Question ONE and any other TWO
QUESTION ONE: 30 MARKS-COMPULSORY
(a)(i) Distinguish between CSMA/CD and CSMA/CA. [4 Marks]
(ii) Where are they applied? [2 Marks]
(b) Briefly describe two similarities and two differences between switches and routers.
[4 Marks]
(c) Briefly discuss the three (3) fundamental characteristics of a data communication
system. [3 Marks]
(d) Briefly discuss any three (3) benefits of the OSI Reference Model. [6 Marks]
(e)(i) Which class does the IPv4 address 130.248.45.89 belong to? Show your working.
[2 Mark]
(ii) What is the Network ID for this IP address? [1 Mark]
(f) Contrast the following:
i). Circuit switching and Packet switching. [2 Marks]
ii). Single mode and Multimode fiber. [2 Marks]
(g) A network topology is a physical layout of the network. Discuss the following
topologies, using appropriate diagrams: Bus and Ring. [4 Marks]
QUESTION TWO
(a) List four (4) functions that are performed by a Network Interface Card (NIC).
[4 Marks]
(b) As a network administrator, you have two options when it comes to assigning IP
addresses to the hosts in your network. Briefly explain:
(i) When it is appropriate to use Static IP configuration option.
[4 Marks]
(ii) When it is appropriate to use Dynamic IP configuration option.
[4 Marks]
(c) Discuss briefly four (4) factors that must be taken into account when deciding
what type of Network Operating System to install on a network. [8 Marks]
QUESTION THREE
(a) You and your friend wish to transfer huge files between your two laptops. It
would take a lot of time to accomplish this task if you decided to use a memory
stick. Your friend asks you to set a simple peer-to-peer network to achieve the
objective.
(i) What equipment do you require to accomplish this task? [4 Marks]
(ii) What type of transmission media would you use? [1 Mark]
(iii) What type of cable will you construct? [1 Mark]
(iv) Which network troubleshooting commands are you likely to use in this
task? [2 Marks]
(v) How will you set up the simple peer-to-peer network of the two laptops?
[2 Marks]
(vi) What configurations are necessary for this task to be accomplishment?
[4 Marks]
(b) 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]
(iii) Impulse and Thermal noise. [2 Marks]
QUESTION FOUR
(a) Internet services often use the so-called client server paradigm. New ad-hoc
networks, on the other hand, use peer-to-peer services. Compare these two ways
and give examples of services or applications. Explain the benefits, drawbacks,
and problems of both paradigms. [6 Marks]
(b) List and briefly explain any three (3) things that computer networks provide to
people. [6 Marks]
(c) Describe the steps a client goes through to get an IP address from a DHCP server.
[6 Marks]
(d) Explain any two (2) possible sources of noise in cables. [2 Marks]
QUESTION FIVE
(a) Explain how wireless LANs communicate. [6 Marks]
(b) Explain why the Four Repeater Rule is important. [3 Marks]
(c) Outline the five (5) components of a data communication system. [5 Marks]
(d) Describe briefly the three components of a fiber optic cable. [3 Marks]
(e) Briefly discuss any two (2) functions of a Network Administrator. [3 Marks]
