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Test your knowledge
Chapter 7 theory
Page 240
Questions 13 – 31
13. Why do manufacturers of network hardware and software follow established standards?
They establish these standards because it will avoid problems associated with incompatibility between
hardware and software components, organisations such as the Institution of Electrical and Electronics
Engineers develop network standards.
14. Briefly describe how an Ethernet network transmits data.
They use cables to transfer data across. The original Ethernet standard is not very fast by today’s
standards. A second Ethernet standard is called Fast Ethernet. They transfer data at speeds of 100Mbps,
up to 10 times faster than the original. They allow personal computers to contend for access to the
network. If two computers try to send data via Ethernet they will collide and must attempt to send
again.
15. In what situations would TCP/IP protocol be most useful?
It manages the transmission of data by breaking it up into packets and transmitting the packets over the
Internet. An important part is the IP address. The IP addressing standard defines a mechanism to
provide a unique address for each computer on the Internet.
16. Explain the term ‘packet switching’.
Packet switching is a technique of breaking a message into individual packets, sending the packets along
the best route available, and then reassembling the data.
17. What network transmission standard would be useful in a situation where an old, heritage-listed
building with solid stone walls needs to be networked?
The 802.11 standard would be best useful in old buildings.
18. Describe how verifying the identity of a user can protect a network?
A username also known as user ID, is a unique combination of characters, such as letters or numbers. By
typing this in, it gives the identity on one specific user. Then a password will be asked that is a secret
combination of characters. Most network operation systems require these combinations correctly
before you access the data.
19. What is a firewall?
A firewall is a general term that refers to hardware or software that restricts access to data and
information on a network. One use of firewalls is to deny network access to outsiders.
20. Describe three measures that should be incorporated into a wireless network to restrict access by
unauthorised users and to secure the transmission of data.
To avoid unauthorised network access, should include firewall. The recommended security ways should
include:

The wireless access point should be configured so that it does not broadcast a network
name. It should also allow access only to specified devices.

Use Wireless Equivalent Privacy, which is a standard that defines how to encrypt data as it
travels across wireless networks.
21. Some communications software support file transfer protocol (FTP). What is the purpose of FTP?
FTP is an Internet standard that allows you to upload and download files to and from a webserver,
called FTP server. To view or use a file on an FTP server, you can download the file from the server to
your computer.
22. What is the purpose of a network interface card?
A network interface card is a card you insert into an expansion slot of a personal computer or other
device, such as a printer, enabling the device to connect to a network.
23. A wireless access point can be wired to the fibre optic backbone of a bus network. What is the
purpose of the wireless access point?
The purpose of a wireless access point is a device that allows computers and devices such as printers to
transmit data wires sly among themselves. They are normally placed near the ceiling.
24. Routers and switches are used to connect separate networks. Explain the circumstances in which
each of these would be used.
A router will connect LANs irrespective of the hardware and network communications protocol used in
each LAN segment.
A switch stores the address of every device down each cable connected to it. When a packet enters the
switch, it uses simple logic to detect the destination of a packet and sends the packet only down the
cable that contains the addressed device.
25. What is the difference between baseband and broadband transmission?
A baseband transmission can only transmit only one single at a time whereas broadband transmission
can transmit multiple signals simultaneously.
26. What is the advantage of using coaxial cable over twisted-pair wire? When would you use twistedpair?
Twisted-pair wire is used for telephone systems. Coaxial cable is used for cable television. It can be
cabled over longer distances that twisted-pair cable can.
27. What advantages does fibre optics have over wire cables?
The advantages fibre optic cables have over wire cables is;

The capability of carrying significantly more signals that wire cables

Faster data transmission

Less susceptibility to noise from other devices

Better security for signals during transmission

Their smaller size (much thinner and lighter)
28. In what circumstances would a network designer consider using wireless transmission media?
They would use it when they want to do broadcast radio, cellular radio, microwaves, communications
satellites and infra-red.
29. Briefly describe the broadcast radio and cellular radio wireless transmission data.
Broadcast radio is a wireless transmission medium that distributes radio signals through the air over
long distances and short distances.
Cellular radio is a form of broadcast radio that is used widely for mobile communications, specifically
wireless modems and mobile phones.
30. What is the main limitation of microwave transmission?
The main limitation for microwave transmission is it must transmit in a straight line with no obstructions
between microwave antennas.
31. Many companies use satellite transmission to access the Internet. Web satellites, however, will
provide faster downlink transmission that uplink transmissions. Why is the difference in speed not of
major concern to these companies?
With satellite Internet connections, the uplink transmission are usually slower than the downlink
transmissions. The difference in speeds is usually acceptable to most Internet satellite users because
they download much more data that they upload.
32. Describe the advantages of setting up a home network.
The advantages of having a home network are, all the computers in the house can be connected to the
Internet at the same time. Each computer can access files and programs on the other computers in the
home. All computers can share the one printer or DVD drive. Each networked computer is able to play
multiplayer video games with other computers.
33. There are four types of home network in common use. Which type would you choose to set up a
network in your home? Why would you choose that type?
A Wi-Fi network. I would choose a Wi-Fi network because I have three computers in my home. The main
computer has a cable connected to it via the router. The router is wireless which gives radio waves
which signals the other two computers to have access to the Internet without any wires or cables
connected to those computers.
34. Identify the four elements of a data flow diagram.
A data flow diagram has four main elements, these are;

Processes, represented by circles

Data stores, drawn as pairs of parallel lines

Data flows, indicated by arrows, and

Sources or entities, drawn as squares