Name: Azza Munez.
Chapter 2: The Landscape-Network devices
1. Why is a Kilobyte equal to 1024 bytes and not 1000 bytes?
A kilobyte represents 1000 bytes (‘kilo means 1000). Technically speaking, as binary
is a base 2 number, a kilobyte is not exactly 1000 bytes, but is equal to 1024 bytes(
which is 2 to the power to 10).
2. What is Moore’s Law and how relevant is it today?
Moore’s law is an observation written by Gordon Moore. He predicted that the
number of transistors that were contained in an area of a CPU would double roughly
every two years.
3. List two ways in which the speed of a CPU can be measured.
CPU can be measured by their clock speed. The clock speed of a CPU is usually
expressed in a number of cycle per second (or Hertz). For e.g. a clock speed could be
2.0GHz (or 2.0 Gigahertz).
4. What is the difference between screen size and screen resolution?
Screen size is purely a physical attribute of a device but the size of a devices screen
may play some part is determining its resolution.
Screen resolution is another attribute of devices which shows us how clear can you
see your screen. E.g. Iphone4 has a DPI of 326 and a screen size of 3.5 inches
diagonally which gives of 640 * 960. Screen resolution can be measured by DPI (Dots
per Inches) or PPI (Pixels per inches).
5. What advantages do SSDs have over HDDs?
The big advantage that SSDs has over HDDs is its speed. It provides faster access
than standard HDDs.
6. What is the difference between a PDA and a smart phone?
There is not much of difference between PDAs and Smart phones the both got the
same functionality. Except there is more addition functionality to the smart phones.
E.g. large range of application and by making phone calls and text messaging.
7. List two common constraints that mobile computing devices have and explain the effect
these could have on software development?
Secondary storage of the mobile computing devices tends to be of lower capacity
(mainly due to size Constraints) and CPUs are often slower (due to the fact that
advances in mobile technology usually follow on from advances in desktop
technology.
8. What does NIC stand for?
NIC stands for Network Interface Cards.
Name: Azza Munez.
9. What is it about the way that a switch works that reduces the number of collisions that occur
compared to a hub?
A Switch is a similar device to a hub. It forwards packets from one device to another
and it can be used to connect one LAN area to another. This reduces the number
collisions happens during sending and receiving data but it does not entirely remove
the collisions. It will still happen during sending and receiving data.
10. Define the term “bandwidth”.
Telecommunication: The smallest range of frequencies constituting a band, within
which particular signal can be transmitted without distortion.
11. Why is network speed measured in bits per second rather than bytes per second?
Because of the capacity of the network is measured in Bytes, Gigabytes and
Terabytes. It’s only the speed that is measured in bytes and Gigabits.
12. What is a protocol?
A protocol is a convention or a standard that controls or enables the connection,
communication and data transfer between competes of networks.
13. Describe what occurs at the Physical layer of the OSI model.
The Physical layer describes the method by which data is transmitted via physical
media. The physical layer also manages connection and disconnection to the from
physical media and physical layer is only concerned about physical media, not data
transfer.
14. TCP/IP consists of two protocols. What do each of these do?
TCP (Transports Control Protocol) is used to divide data that needs to be transmitted
into a number of packets each with sequence number.
IP (Internet Protocol) Defines how the data is sent between networks nodes.
15. What is the main advantage of using a VPN?
The main advantage for VPN (Virtual private network) over using the internet is
Security. In connecting to a VPN. The client and the server will exchange encryptions
code to make sure the communication is totally secure.
Name: Azza Munez.