Practical lesson 8, 9 Networking and Telecommunications
The objective of the lesson:
To introduce students about how computers are connected with each other.
To provide with information about the design, installation and improvement of computer networks and related software.
Checking reports on given topics at the lecture
What are the two basic network configurations?
The two basic network configurations are peer-to-peer and server-based.
A primary reason for implementing a network is to _______ resources.
share
Name three key resources often shared on a network.
In a peer-to-peer network, each computer can act as a _________ and a ________.
server, client
What is the function of a server in a server-based network?
A server provides services and resources to the network.
A peer-to-peer network is adequate if _____________ is not an issue.
security
Network professionals use the term _________ to refer to the network's physical layout.
topology
The four basic topologies are the _______, ________, ________, and _________ topologies.
bus, star, ring, and mesh
In a ________ topology all segments are connected to a centralized component called a __________.
star, hub
In a ________ topology, a break anywhere in the cable will cause the entire network to go down.
bus
Presentation stage:
Presenting the theme of the lesson: the “Networking and Telecommunications”
Telecommunication system - enable the transmission of data over public or private networks
Network - a communications, data exchange, and resource-sharing system created by linking two or more computers and establishing standards, or protocols, so that they can work together.
Networks are differentiated by the following:
Architecture - peer-to-peer, client/server
Topology - bus, star, ring, hybrid, wireless
Protocols - Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP)
Media - coaxial, twisted-pair, fiber-optic
The three types of networks include:
Local area network (LAN)
Metropolitan area network (MAN)
Wide area network (WAN)
Architecture
There are two primary types of architectures
Peer-to-peer (P2P) network
Client/server network
Peer-to-peer: is the simplest type of network; every computer can communicate directly with every other computer
Advantages
Simple to configure (Most home networks are P2P)
Typically less expensive to setup and maintain than other types of networks.
Disadvantages
Not very flexible: as P2P networks grow, adding or changing significant elements of the network can be difficult
Not very secure: data and other resources shared by network users can be easily discovered and used by unauthorized users
Resource Sharing is not practical: each user is responsible for configuring Shared Docs and preventing access to other files: Meaning resource sharing is not controlled by a central computer or authority
Client/Server Networks
Client/Server networks: use a central computer, known as a Server to facilitate communication and resource sharing between other computers on a network, which are known as Clients.
In terms of resource sharing you can compare the client/server network to a public library: Librarians manages the use of books and other media by patrons, a server manages the use of shared resources by clients…
Advantages of a Client/Server Network
Provide User logon accounts and passwords for user of the network
Access to multiple shared resources can be centrally granted to a single user or groups of users
Problems on the network can be tracked, diagnosed and often fixed from one location
Optimized for faster processing time to handle many requests from clients
Larger disk space means it is more scalable and more clients can be added as necessary
Topology
Network topology - refers to the geometric arrangement of the actual physical organization of the computers and other network devices) in a network
1)Bus 2) Star 3) Ring 4) Hybrid 5)Wireless
Bus Topology (linear bus)
All devices are connected to a central cable, called the bus or backbone. These networks are relatively inexpensive and easy to install for small networks
Star Topology
All devices are connected to a central device, called a hub. Star networks are relatively easy to install & manage, but bottlenecks can occur because all data must pass through the hub
Ring Topology
The ring topology connects computers on a single circle of cable. Signals travel around the loop in one direction and pass through each computer acting like a repeater to boost the signal and send it on to the next computer.
Hybrid Topology
Groups of star-configured workstations are connected to a linear bus backbone cable, combining the characteristics of bus and star topologies
Wireless
Devices are connected by a receiver/transmitter to a special network interface card that transmits signals between a computer and a server---all with an acceptable transmission range
Practical work 1.
Students are given crossword about computer networks
Across
1. Another name for a computer on network
2. The network topology which has a server in the middle
3. This usually connects LAN together
Down
1. The machine that stores datas and files
2. This tells the server who you are and which files to present to you
3. This keeps your user area secure
4. Hardware that can be connected to a network and shared
5. The software that keeps the network safe from hackers and viruses
6. The network topology which sends data in one direction only
Key
Across 1. workstation 2. Star 3. Cable
Down 1. fileserver 2. Username 3. password
4. peripheral 5. Firewall 6. Ring
Practical work 2
Match the words 1-8 to the descriptions a-g.
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Answer key:
2f 3g 4h 5a 6b 7e
Practical work 3.
The Web
Match the sentence beginnings (1-5) with the correct endings (a-e).
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Practical work 4
Answer the question (Quiz maker program has been used in creating the following test)
I. What is determined by the choice of network topology?
Select all the right answers.
a. network cost +
b. network reliability +
c. Network performance +
d. extensible network +
e. control network+
II. A method of computer interaction and the nature of the spread of the network signal is:
a. physical topology
b. logical topology +
c. network protocol
III. Note the basic topology on which networks are (choose three answers).
a. bus + b. tree c. star +
d. reticular e. hybrid
f. ring +
IV. What is the main drawback of the topology of "tire"?
a. high cost of network
b. low reliability of the network +
c. large cable consumption
d. low noise immunity of the network
V. What is the main drawback of the topology of the "ring"?
a. high cost of network +
b. low reliability networks
c. large cable consumption
d. low noise immunity of the network
VI. What is the main advantage of the topology of "star"?
a. lower network costs
b. Small cable consumption
c. good noise immunity network
d. high reliability and manageability of the network +
Practical lesson 10
Cybersecurity. Threats to Information Security. Methods of information security. Means of protection of information systems. Software and technical measures to ensure information security. Cryptographic data protection.
Objective: To inform the students about security risks and its classification
Practical work 1.
Internet security
Match the captions (1-4) with the pictures (a-d).
A secure website can be recognized in two ways: the address bar shows the letters http and a closed padlock or key is displayed at the bottom of the screen.
You have to type your username and password to access a locked computer system.
This program display a message when it detects spyware and other unwanted software that may compromise your privacy or damage your computer
Private networks use a software and/or hardware mechanism called a firewall to block unauthorized traffic from the Internet.
Answer key: 1d, 2c, 3a, 4b
Practical work 2.
Internet security
Answer key:
Practical work 3.
Match the Items:
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Answer key: 1e, 2a, 3c, 4b, 5d
Practical work 4.
Read the descriptions 1-8. Match the words in the box to the descriptions.
Answer key:
Practical work 5.
Read the text on security and match the headings in the box with the paragraphs 1-5.
Answer key:
