COMPUTER & NETWORK TECHNOLOGY

SECTION A

Answer 2 questions (out of 4).

A1

All information inside a computer is represented in the form of strings of 1s and 0s.

There are many ways of representing numeric values in everyday life; for example,

Integer 123

Negative integer -32

Fraction 0.123

Floating-point 1.124 x 10^-6

How is a computer able to represent each of these values in binary form? Explain the advantage and disadvantage of each system of numeric representation and its limitations.

Your answer should include considerations such as word-length, accuracy, range, and the complexity of performing operations in each system.

A2

a) The inner (dot) product S of two vectors A and B is defined as S =Σa_i.b_i for i = 0 to n-1; that is, S = a₀.b₀ + a₁.b₁ + … + a_n-1.b_n-1

Assuming that vectors A and B are located in main memory, write an assembly language program to calculate S. Note that a vector is a sequence of consecutive values; for example, A = a₀, a1, a₂, … , a_n-1.

You may use any assembly language, although you must explain the action of each instruction you use. Your program should be documented.

b) Year by year, microprocessors have become faster and faster. Part of the increase in speed is due to advances in semiconductor manufacturing technology and part of the increase in speed is due to advances in computer architecture and organization. Briefly explain two of the advances in computer architecture and organization that have significantly improved computer performance.

A3

Computer networks are associated with various types of hardware. A modern home or office may include the following items of hardware:

Modem

Hub

Wi-Fi router

Explain what role each of these devices performs in a typical installation and why they are needed to provide safe networking facilities.

A4

a) Computer performance is regarded as important today; users want the best performance possible for the computers they buy.

Discuss the factors that contribute to the overall performance of a desk-top computer.

Explain how the performance of computers is measured today and how different computers are compared. Your answer should include several ways by which computer performance can be measured and you should comment on the accuracy/relevance of each of the measurement techniques.

b) Why has power dissipation (i.e., heat) become one of the principal limiting factors of modern computer performance?

SECTION B

Answer 5 questions (out of 8).

B5

a) Briefly explain the role of TCP/IP in network management.

b) Describe the different layers of the TCP/IP model.

B6

a) Describe THREE security threats that computer users face today.

b) Give THREE measures that can be taken to deal with these threats.

B7 Describe the characteristics and typical uses of the following:

a) VLAN

b) Intranet

B8 Briefly describe the features and uses of the following:

a) DRAM

b) USB drive (flash memory)

c) Hard disk

B9 Briefly describe the features and uses of the following in the context of networking:

a) RJ45

b) HDMI

c) Fibre optics

d) CAT5

B10 What would an IT technician understand by the following terms:

a) Bandwidth

b) Ipconfig

c) FAT32

d) Proxy server

B11

a) Explain why a hierarchical file structure is needed in a computer system.

b) Describe THREE file formats that might be used in a typical computer.

B12 Describe the key functions of a modern operating system.