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IWT711S - INTERNET and WAN TELECOM - 1ST OPP - JUNE 2022 |
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nAm I BI A un IVE RSITY
OF SCIEn CE Ano TECH n OLOGY
Faculty of Computing and Informatics
Department of Computer Science
QUALIFICATION:Bachelor of Computer Science in Cyber Security
Bachelor of Compter Science
QUALIFICATIONCODE: 07BCCS;07BACS
LEVEL: 7
COURSE: Internet and WAN Telecommunications
COURSECODE: IWT711S
DATE:June 2022
SESSION: 1
DURATION: 2 hours
MARKS: 70
FIRSTOPPORTUNITY EXAMINATION QUESTION PAPER
EXAMINER{S}
Mr. Nasimane Ekandjo
MODERATOR:
Mr. Kudakwashe Madzima
THIS QUESTION PAPERCONSISTSOF 4 PAGES
{Excluding this front page}
INSTRUCTIONS
1. Answer ALL the questions.
2. Write clearly and neatly.
3. Number the answers clearly.
4. When answering questions you should be guided by the allocation
of marks. Do not give too few or too many facts in your answers.
PERMISSIBLEMATERIALS
1. None
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Question 1 [13 Marks]
Section A [13 marks]
Below are multiple choice questions as well as True/ False questions. Select the correct answers.
1.1 Which of the following is the correct network address for the 1Pv6node with 1Pv6address?
a) 2000:3000:8B74:0130:2E0:8FFF:FE89:1A02/64?
b) 2000::2E0:8FFF:FE89:1A02/64
c)
2000:3000:8B74:0130::/64
d)
None of the above
1.2 Which multiplexing technique involves signals composed of light beams?
a)
TOM
b)
FOM
c)
WOM
d)
None of the above
1.3 In the transmission of terrestrial microwaves __ can regenerate the signal at each antenna.
a) repeaters
b) bridges
c)
routers
d) any of the above
1.4 Which of the following is a digital multiplexing method?
a)
FOM
b) Asynchronous TOM
c)
Synchronous TOM
d) band c
1.5 An ATM cell has the payload field of
a)
32 bytes
b) 48 bytes
c)
64 bytes
d)
128 bytes
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1.6 The ___ is the maximum value/strength of signal over time.
a}
phase
b} frequency
c}
bandwidth
d} peak amplitude
1.7 Which two DHCPpacket types contain an IP address to be leased to a client?
a}
Offer and Release
b}
Offer and NAK
c}
Offer and Acknowledgement
d}
Offer and Renew
e}
None of the above
1.8 In frame relay networks, extended address is used __ _
a} to increase the range of data link connection identifiers
b} for error detection
c} for encryption
d} for error recovery
1.9 DHCPis a TCPService and it runs on port 21 and 23.
a} False
b} True
1.10 1Pv6have fewer header fields compared to 1Pv4.
a} True
b} False
1.11 With unguided media, the antenna is considered more important in terms of the bandwidth
produced.
a} False
b} True
1.12 Inside global - is the actual address assigned to an inside host (private address}.
b} False
b} True
1.13 In Analog WANs, modems are used to convert digital data to analog and vice versa.
a} True
b} False
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Section B [57 marks]
Question 2
Explain the concepts crosstalk as used in internet and WAN telecommunications.
[2]
Question 3
Name two transmission impairments in wireless transmission
[2]
Question 4
4.1 The maximum rate at which data can be transmitted over a given communication path, or
channel, under given conditions, is referred to as the channel capacity. Mention four factors
that affect channel capacity.
[4]
4.2 What the three causes signal degradation and bit errors between signal received and signal
transmitted?
[3]
Question 5
5.1 Why must a satellite have distinct uplink and downlink frequencies?
[2]
5.2 What factors determine antenna gain?
[2]
5.3 What is the primary cause of signal loss in satellite communications?
[2]
Question 6
6.1 Define multiplexing.
[2]
6.2 If the analog signals are multiplexed, then it is referred to as analog multiplexing. Similarly, if
the digital signals are multiplexed, then it is referred to as digital multiplexing. From the types
of multiplexing below, choose whether they are part of analog or digital multiplexing. [4]
Frequency Division Multiplexing
Synchronous Time Division Multiplexing
Asynchronous Time Division Multiplexing
Wavelength Division Multiplexing
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6.3 Name the steps that are used when packets are sent in Frequency Division Multiplexing
{FDM)
[4]
Question 7
Using your own words, explain the fundamental differences between how analog and digital signals
are propagated.
[6]
Question 8
Explain two advantages and two disadvantages of twisted pair cable.
[4]
Question 9
State three advantages of IPv6 over IPv4.
[3]
Question 10
Name and explain three factors that need to be considered when choosing the transmission media.
[6]
Question 11
11.1 What is NAT?
[2]
11.2 Explain three methods that can be used to implement NAT.
11.3
Consider the figure below and answer the questions that follows:
Static NAT Translation
$9.1.1.2= 192.168.1.5
g---10_.1_.1_.1
HostA
10.1.1.10
55.1.1.1
RouterA
NAT-Enabled
Internet )
~_)
RouterA
NAT-Enabled
Consider a connection from HostA to HostB:
Identify the NAT addresses for the following:
Inside Local Address: ------
Inside Global Address: ____
_
Outside Global Address: ____
_
End of paper
4
[6]
HostB.
192.168.1.5
[3]